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Methods Matter: Improving causal Inference in Educational and Social Science Research by Richard J. Murnane and John B. Willett Chapter 10: Introducing Instrumental-Variables Estimation | SAS Textbook Examples

You can download the data for this chapter by clicking here:
https://stats.idre.ucla.edu/wp-content/uploads/2016/02/dee.sas7bdat.

(a) Univariate Statistics from Table 10.1 on page 207.

proc univariate data=dee;
   var register college;
run;


                                     The UNIVARIATE Procedure
                Variable:  register  (Is respondent currently registered to vote?)

                                             Moments

                 N                        9227    Sum Weights               9227
                 Mean               0.67085727    Sum Observations          6190
                 Std Deviation      0.46992736    Variance            0.22083173
                 Skewness           -0.7273222    Kurtosis            -1.4713213
                 Uncorrected SS           6190    Corrected SS        2037.39352
                 Coeff Variation     70.048785    Std Error Mean      0.00489216


                                    Basic Statistical Measures
 
                          Location                    Variability

                      Mean     0.670857     Std Deviation            0.46993
                      Median   1.000000     Variance                 0.22083
                      Mode     1.000000     Range                    1.00000
                                            Interquartile Range      1.00000


                                    Tests for Location: Mu0=0
 
                         Test           -Statistic-    -----p Value------

                         Student's t    t  137.1291    Pr > |t|    <.0001
                         Sign           M      3095    Pr >= |M|   <.0001
                         Signed Rank    S   9580573    Pr >= |S|   <.0001


                                     Quantiles (Definition 5)
 
                                      Quantile      Estimate

                                      100% Max             1
                                      99%                  1
                                      95%                  1
                                      90%                  1
                                      75% Q3               1
                                      50% Median           1
                                      25% Q1               0
                                      10%                  0
                                      5%                   0
                                      1%                   0
                                      0% Min               0


                                     The UNIVARIATE Procedure
                Variable:  register  (Is respondent currently registered to vote?)

                                       Extreme Observations
 
                               ----Lowest----        ----Highest---
 
                               Value      Obs        Value      Obs

                                   0     9227            1     9221
                                   0     9222            1     9223
                                   0     9220            1     9224
                                   0     9218            1     9225
                                   0     9217            1     9226

                                     The UNIVARIATE Procedure
            Variable:  college  (Attended junior, community or 4year college by 1984?)

                                             Moments

                 N                        9227    Sum Weights               9227
                 Mean               0.54709006    Sum Observations          5048
                 Std Deviation      0.49780456    Variance            0.24780938
                 Skewness            -0.189232    Kurtosis            -1.9646171
                 Uncorrected SS           5048    Corrected SS        2286.28937
                 Coeff Variation    90.9913372    Std Error Mean      0.00518237


                                    Basic Statistical Measures
 
                          Location                    Variability

                      Mean     0.547090     Std Deviation            0.49780
                      Median   1.000000     Variance                 0.24781
                      Mode     1.000000     Range                    1.00000
                                            Interquartile Range      1.00000


                                    Tests for Location: Mu0=0
 
                         Test           -Statistic-    -----p Value------

                         Student's t    t  105.5675    Pr > |t|    <.0001
                         Sign           M      2524    Pr >= |M|   <.0001
                         Signed Rank    S   6371838    Pr >= |S|   <.0001


                                     Quantiles (Definition 5)
 
                                      Quantile      Estimate

                                      100% Max             1
                                      99%                  1
                                      95%                  1
                                      90%                  1
                                      75% Q3               1
                                      50% Median           1
                                      25% Q1               0
                                      10%                  0
                                      5%                   0
                                      1%                   0
                                      0% Min               0


                                     The UNIVARIATE Procedure
            Variable:  college  (Attended junior, community or 4year college by 1984?)

                                       Extreme Observations
 
                               ----Lowest----        ----Highest---
 
                               Value      Obs        Value      Obs

                                   0     9226            1     9219
                                   0     9224            1     9221
                                   0     9222            1     9223
                                   0     9220            1     9225
                                   0     9218            1     9227

	

Cross-tabulation of register and college, with
a chi-squared test. (Not shown in the text.)

proc freq data=dee;
   table register*college / chisq cellchi2 expected;
run;

 
                                        The FREQ Procedure

                                   Table of register by college

                            register(Is respondent currently registered to vote?)
                                            college(Attended junior, community or 4year college 
                                                    by 1984?)

                            Frequency      
                            Expected       
                            Cell Chi-Square
                            Percent        
                            Row Pct        
                            Col Pct               0       1  Total
                            
                                         0    1780    1257    3037
                                            1375.5  1661.5 
                                            118.96  98.483 
                                             19.29   13.62   32.91
                                             58.61   41.39 
                                             42.59   24.90 
                            
                                         1    2399    3791    6190
                                            2803.5  3386.5 
                                            58.366  48.319 
                                             26.00   41.09   67.09
                                             38.76   61.24 
                                             57.41   75.10 
                            
                            Total              4179     5048     9227
                                              45.29    54.71   100.00


                                        The FREQ Procedure

                           Statistics for Table of register by college

                      Statistic                     DF       Value      Prob
                      
                      Chi-Square                     1    324.1293    <.0001
                      Likelihood Ratio Chi-Square    1    324.2767    <.0001
                      Continuity Adj. Chi-Square     1    323.3285    <.0001
                      Mantel-Haenszel Chi-Square     1    324.0942    <.0001
                      Phi Coefficient                       0.1874          
                      Contingency Coefficient               0.1842          
                      Cramer's V                            0.1874          


                                       Fisher's Exact Test
                                
                                Cell (1,1) Frequency (F)      1780
                                Left-sided Pr <= F          1.0000
                                Right-sided Pr >= F      1.270E-72
                                                                  
                                Table Probability (P)    1.573E-72
                                Two-sided Pr <= P        2.092E-72
           	

(b) Sample Bivariate Correlations and Covariances from Table 10.1 on page 207.

proc corr data=dee cov;
   var register college;
run;

                                       The CORR Procedure

                                 2  Variables:    register college  


                                   Covariance Matrix, DF = 9226
 
                                                                         register         college

 register    Is respondent currently registered to vote?             0.2208317276    0.0438448426
 college     Attended junior, community or 4year college by 1984?    0.0438448426    0.2478093831


                                        Simple Statistics
 
    Variable           N          Mean       Std Dev           Sum       Minimum       Maximum

    register        9227       0.67086       0.46993          6190             0       1.00000
    college         9227       0.54709       0.49780          5048             0       1.00000

                                        Simple Statistics
 
                 Variable    Label

                 register    Is respondent currently registered to vote?         
                 college     Attended junior, community or 4year college by 1984?


                           Pearson Correlation Coefficients, N = 9227 
                                    Prob > |r| under H0: Rho=0
 
                                                                   register       college

         register                                                   1.00000       0.18743
         Is respondent currently registered to vote?                               <.0001

         college                                                    0.18743       1.00000
         Attended junior, community or 4year college by 1984?        <.0001              
     

(c) OLS Regression Analysis: Outcome=register from Table 10.1 on page 207.

proc glm data=dee;
   model register = college;
run;


                                        The GLM Procedure

                             Number of Observations Read        9227
                             Number of Observations Used        9227

                                        The GLM Procedure
 
Dependent Variable: register   Is respondent currently registered to vote?

                                               Sum of
       Source                      DF         Squares     Mean Square    F Value    Pr > F

       Model                        1       71.570283       71.570283     335.86    <.0001

       Error                     9225     1965.823236        0.213097                     

       Corrected Total           9226     2037.393519                                     


                      R-Square     Coeff Var      Root MSE    register Mean

                      0.035128      68.81117      0.461625         0.670857


       Source                      DF       Type I SS     Mean Square    F Value    Pr > F

       college                      1     71.57028291     71.57028291     335.86    <.0001


       Source                      DF     Type III SS     Mean Square    F Value    Pr > F

       college                      1     71.57028291     71.57028291     335.86    <.0001


                                                  Standard
                Parameter         Estimate           Error    t Value    Pr > |t|

                Intercept     0.5740607801      0.00714090      80.39      <.0001
                college       0.1769297112      0.00965436      18.33      <.0001
	

(a) Univariate Statistics from Table 10.2 on page 219. Note that only the variable distance has
been added from panel a of Table 10.1.

proc univariate data=dee;
   var distance;
run;


                                     The UNIVARIATE Procedure
             Variable:  distance  (Miles from respondents HS to nearest 2yr college)

                                             Moments

                 N                        9227    Sum Weights               9227
                 Mean               9.73599232    Sum Observations    89834.0011
                 Std Deviation      8.70228565    Variance            75.7297756
                 Skewness           1.18127321    Kurtosis            0.60086158
                 Uncorrected SS     1573306.05    Corrected SS        698682.909
                 Coeff Variation    89.3826265    Std Error Mean      0.09059476


                                    Basic Statistical Measures
 
                          Location                    Variability

                      Mean     9.735992     Std Deviation            8.70229
                      Median   7.000000     Variance                75.72978
                      Mode     5.000000     Range                   35.00000
                                            Interquartile Range     12.00000


                                    Tests for Location: Mu0=0
 
                         Test           -Statistic-    -----p Value------

                         Student's t    t  107.4675    Pr > |t|    <.0001
                         Sign           M    4443.5    Pr >= |M|   <.0001
                         Signed Rank    S  19746914    Pr >= |S|   <.0001


                                     Quantiles (Definition 5)
 
                                      Quantile      Estimate

                                      100% Max            35
                                      99%                 35
                                      95%                 30
                                      90%                 25
                                      75% Q3              15
                                      50% Median           7
                                      25% Q1               3
                                      10%                  1
                                      5%                   1
                                      1%                   0
                                      0% Min               0


                                     The UNIVARIATE Procedure
             Variable:  distance  (Miles from respondents HS to nearest 2yr college)

                                       Extreme Observations
 
                               ----Lowest----        ----Highest---
 
                               Value      Obs        Value      Obs

                                   0     9048           35     9081
                                   0     9047           35     9082
                                   0     9046           35     9083
                                   0     9045           35     9084
                                   0     9044           35     9085
	

(b) Sample Bivariate Correlations and Covariances from Table 10.2 on page 219.

proc corr data=dee cov;
   var register college distance;
run;


                                        The CORR Procedure

                            3  Variables:    register college  distance 


                                   Covariance Matrix, DF = 9226
 
                                                                         register         college

 register    Is respondent currently registered to vote?               0.22083173      0.04384484
 college     Attended junior, community or 4year college by 1984?      0.04384484      0.24780938
 distance    Miles from respondents HS to nearest 2yr college         -0.13687315     -0.48247222

                                   Covariance Matrix, DF = 9226
 
                                                                                 distance

         register    Is respondent currently registered to vote?              -0.13687315
         college     Attended junior, community or 4year college by 1984?     -0.48247222
         distance    Miles from respondents HS to nearest 2yr college         75.72977557


                                        Simple Statistics
 
    Variable           N          Mean       Std Dev           Sum       Minimum       Maximum

    register        9227       0.67086       0.46993          6190             0       1.00000
    college         9227       0.54709       0.49780          5048             0       1.00000
    distance        9227       9.73599       8.70229         89834             0      35.00000

                                        Simple Statistics
 
                 Variable    Label

                 register    Is respondent currently registered to vote?         
                 college     Attended junior, community or 4year college by 1984?
                 distance    Miles from respondents HS to nearest 2yr college    


                           Pearson Correlation Coefficients, N = 9227 
                                    Prob > |r| under H0: Rho=0
 
                                                            register       college      distance

  register                                                   1.00000       0.18743      -0.03347
  Is respondent currently registered to vote?                               <.0001        0.0013

  college                                                    0.18743       1.00000      -0.11137
  Attended junior, community or 4year college by 1984?        <.0001                      <.0001

  distance                                                  -0.03347      -0.11137       1.00000
  Miles from respondents HS to nearest 2yr college            0.0013        <.0001              
    

(c) Method-of-Moments IVE Estimate from Table 10.2 on page
219 can be done as a hand calculation: -.136873/-.482472 = .28369107

Table 10.3 on page 228.

proc syslin data=dee 2sls;
   endogenous  college;
   instruments distance;
   model college = distance;
   model register = college;
run;

                                       The SYSLIN Procedure
                                Two-Stage Least Squares Estimation

            Model                                                              college
            Dependent Variable                                                 college
            Label                 Attended junior, community or 4year college by 1984?


                                       Analysis of Variance
 
                                             Sum of        Mean
              Source                 DF     Squares      Square    F Value    Pr > F

              Model                   1    28.35903    28.35903     115.86    <.0001
              Error                9225    2257.930    0.244762                     
              Corrected Total      9226    2286.289                                 


                      Root MSE             0.49473    R-Square       0.01240
                      Dependent Mean       0.54709    Adj R-Sq       0.01230
                      Coeff Var           90.43015                          


                                       Parameter Estimates
 
                          Parameter    Standard                           Variable
   Variable         DF     Estimate       Error    t Value    Pr > |t|    Label

   Intercept         1     0.609118    0.007729      78.81      <.0001    Intercept           
   distance          1     -0.00637    0.000592     -10.76      <.0001    Miles from          
                                                                          respondents HS to   
                                                                          nearest 2yr college 

                                       The SYSLIN Procedure
                                Two-Stage Least Squares Estimation

                Model                                                    register
                Dependent Variable                                       register
                Label                 Is respondent currently registered to vote?


                                       Analysis of Variance
 
                                             Sum of        Mean
              Source                 DF     Squares      Square    F Value    Pr > F

              Model                   1    2.282356    2.282356      10.57    0.0012
              Error                9225    1991.882    0.215922                     
              Corrected Total      9226    2037.394                                 


                      Root MSE             0.46467    R-Square       0.00114
                      Dependent Mean       0.67086    Adj R-Sq       0.00104
                      Coeff Var           69.26575                          


                                       Parameter Estimates
 
                          Parameter    Standard                           Variable
   Variable         DF     Estimate       Error    t Value    Pr > |t|    Label

   Intercept         1     0.515653    0.047982      10.75      <.0001    Intercept           
   college           1     0.283691    0.087258       3.25      0.0012    Attended junior,    
                                                                          community or 4year  
                                                                          college by 1984?  
	

Table 10.4 on page 235.

proc syslin data=dee 3sls;
   endogenous  college;
   instruments distance;
   model college = distance;
   model register = college;
run;


                                       The SYSLIN Procedure
                                Two-Stage Least Squares Estimation

            Model                                                              college
            Dependent Variable                                                 college
            Label                 Attended junior, community or 4year college by 1984?


                                       Analysis of Variance
 
                                             Sum of        Mean
              Source                 DF     Squares      Square    F Value    Pr > F

              Model                   1    28.35903    28.35903     115.86    <.0001
              Error                9225    2257.930    0.244762                     
              Corrected Total      9226    2286.289                                 


                      Root MSE             0.49473    R-Square       0.01240
                      Dependent Mean       0.54709    Adj R-Sq       0.01230
                      Coeff Var           90.43015                          


                                       Parameter Estimates
 
                          Parameter    Standard                           Variable
   Variable         DF     Estimate       Error    t Value    Pr > |t|    Label

   Intercept         1     0.609118    0.007729      78.81      <.0001    Intercept           
   distance          1     -0.00637    0.000592     -10.76      <.0001    Miles from          
                                                                          respondents HS to   
                                                                          nearest 2yr college 

                                       The SYSLIN Procedure
                                Two-Stage Least Squares Estimation

                Model                                                    register
                Dependent Variable                                       register
                Label                 Is respondent currently registered to vote?


                                       Analysis of Variance
 
                                             Sum of        Mean
              Source                 DF     Squares      Square    F Value    Pr > F

              Model                   1    2.282356    2.282356      10.57    0.0012
              Error                9225    1991.882    0.215922                     
              Corrected Total      9226    2037.394                                 


                      Root MSE             0.46467    R-Square       0.00114
                      Dependent Mean       0.67086    Adj R-Sq       0.00104
                      Coeff Var           69.26575                          


                                       Parameter Estimates
 
                          Parameter    Standard                           Variable
   Variable         DF     Estimate       Error    t Value    Pr > |t|    Label

   Intercept         1     0.515653    0.047982      10.75      <.0001    Intercept           
   college           1     0.283691    0.087258       3.25      0.0012    Attended junior,    
                                                                          community or 4year  
                                                                          college by 1984?    


                                       The SYSLIN Procedure
                               Three-Stage Least Squares Estimation

                                      Cross Model Covariance
 
                                              college      register

                               college       0.244762      -.026459
                               register      -.026459      0.215922


                                     Cross Model Correlation
 
                                              college      register

                               college        1.00000      -0.11510
                               register      -0.11510       1.00000


                                 Cross Model Inverse Correlation
 
                                              college      register

                               college        1.01342       0.11664
                               register       0.11664       1.01342


                                  Cross Model Inverse Covariance
 
                                              college      register

                               college        4.14045       0.50738
                               register       0.50738       4.69347


                              System Weighted MSE            1.0462
                              Degrees of freedom              18450
                              System Weighted R-Square     0.007011


            Model                                                              college
            Dependent Variable                                                 college
            Label                 Attended junior, community or 4year college by 1984?



                                       The SYSLIN Procedure
                               Three-Stage Least Squares Estimation

                                       Parameter Estimates
 
                          Parameter    Standard                           Variable
   Variable         DF     Estimate       Error    t Value    Pr > |t|    Label

   Intercept         1     0.609118    0.007729      78.81      <.0001    Intercept           
   distance          1     -0.00637    0.000592     -10.76      <.0001    Miles from          
                                                                          respondents HS to   
                                                                          nearest 2yr college 


                                       The SYSLIN Procedure
                               Three-Stage Least Squares Estimation

                Model                                                    register
                Dependent Variable                                       register
                Label                 Is respondent currently registered to vote?


                                       Parameter Estimates
 
                          Parameter    Standard                           Variable
   Variable         DF     Estimate       Error    t Value    Pr > |t|    Label

   Intercept         1     0.515653    0.047982      10.75      <.0001    Intercept           
   college           1     0.283691    0.087258       3.25      0.0012    Attended junior,    
                                                                          community or 4year  
                                                                          college by 1984?  
	

Table 10.5 on page 240.

proc syslin data=dee 2sls;
   endogenous  college;
   instruments distance black hispanic otherrace;
   model college = distance black hispanic otherrace ;
   model register = college black hispanic otherrace ;
run;

                                       The SYSLIN Procedure
                                Two-Stage Least Squares Estimation

            Model                                                              college
            Dependent Variable                                                 college
            Label                 Attended junior, community or 4year college by 1984?


                                       Analysis of Variance
 
                                             Sum of        Mean
              Source                 DF     Squares      Square    F Value    Pr > F

              Model                   4    49.70516    12.42629      51.24    <.0001
              Error                9222    2236.584    0.242527                     
              Corrected Total      9226    2286.289                                 


                      Root MSE             0.49247    R-Square       0.02174
                      Dependent Mean       0.54709    Adj R-Sq       0.02132
                      Coeff Var           90.01632                          


                                       Parameter Estimates
 
                          Parameter    Standard                           Variable
   Variable         DF     Estimate       Error    t Value    Pr > |t|    Label

   Intercept         1     0.643146    0.009053      71.04      <.0001    Intercept           
   distance          1     -0.00692    0.000595     -11.64      <.0001    Miles from          
                                                                          respondents HS to   
                                                                          nearest 2yr college 
   black             1     -0.05766    0.015959      -3.61      0.0003    Is respondent black?
   hispanic          1     -0.11621    0.013257      -8.77      <.0001    Is respondent       
                                                                          hispanic?           
   otherrace         1     0.033708    0.024010       1.40      0.1604    Is respondent of    
                                                                          another race?       


                                       The SYSLIN Procedure
                                Two-Stage Least Squares Estimation

                Model                                                    register
                Dependent Variable                                       register
                Label                 Is respondent currently registered to vote?


                                       Analysis of Variance
 
                                             Sum of        Mean
              Source                 DF     Squares      Square    F Value    Pr > F

              Model                   4    9.261561    2.315390      10.85    <.0001
              Error                9222    1967.204    0.213316                     
              Corrected Total      9226    2037.394                                 


                      Root MSE             0.46186    R-Square       0.00469
                      Dependent Mean       0.67086    Adj R-Sq       0.00425
                      Coeff Var           68.84653                          


                                       Parameter Estimates
 
                          Parameter    Standard                           Variable
   Variable         DF     Estimate       Error    t Value    Pr > |t|    Label

   Intercept         1     0.526600    0.046306      11.37      <.0001    Intercept           
   college           1     0.248862    0.080601       3.09      0.0020    Attended junior,    
                                                                          community or 4year  
                                                                          college by 1984?    
   black             1     0.061733    0.015174       4.07      <.0001    Is respondent black?
   hispanic          1     0.028293    0.014832       1.91      0.0565    Is respondent       
                                                                          hispanic?           
   otherrace         1     -0.10667    0.022819      -4.67      <.0001    Is respondent of    
                                                                          another race?       
	

The analyses in Tables 10.6 and 10.7 include a variable that is restricted,
so these analyses cannot be reproduced using the available dataset.

Table 10.8 from page 249. Note that many of the coefficients in the first stage models
are equal to 0.

* Form interaction terms;
* Then form interactions between instruments and exog race variables as instruments;
data dee;
   set dee;
   distxblack  = distance*black;
   distxhispanic   = distance*hispanic;
   distxotherrace = distance*otherrace;

   collegexblack  = college*black;
   collegexhispanic   = college*hispanic;
   collegexotherrace = college*otherrace;
run;

proc syslin data=dee 2sls;
   endogenous  college collegexblack collegexhispanic collegexotherrace;
   instruments distance black hispanic otherrace distxblack distxhispanic distxotherrace;
   model college = distance black hispanic otherrace distxblack distxhispanic distxotherrace;
   model collegexblack = distance black hispanic otherrace distxblack distxhispanic distxotherrace;
   model collegexhispanic = distance black hispanic otherrace distxblack distxhispanic distxotherrace;
   model collegexotherrace = distance black hispanic otherrace distxblack distxhispanic distxotherrace;
   model register = college black hispanic otherrace collegexblack collegexhispanic collegexotherrace;
run;

                                       The SYSLIN Procedure
                                Two-Stage Least Squares Estimation

            Model                                                              college
            Dependent Variable                                                 college
            Label                 Attended junior, community or 4year college by 1984?


                                       Analysis of Variance
 
                                             Sum of        Mean
              Source                 DF     Squares      Square    F Value    Pr > F

              Model                   7    50.20795    7.172564      29.57    <.0001
              Error                9219    2236.081    0.242551                     
              Corrected Total      9226    2286.289                                 


                      Root MSE             0.49250    R-Square       0.02196
                      Dependent Mean       0.54709    Adj R-Sq       0.02122
                      Coeff Var           90.02084                          


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    0.645183   0.010058     64.15     <.0001   Intercept           
  distance                 1    -0.00711   0.000723     -9.83     <.0001   Miles from          
                                                                           respondents HS to   
                                                                           nearest 2yr college 
  black                    1    -0.06506   0.022762     -2.86     0.0043   Is respondent black?
  hispanic                 1    -0.12759   0.019368     -6.59     <.0001   Is respondent       
                                                                           hispanic?           
  otherrace                1    0.058954   0.035074      1.68     0.0928   Is respondent of    
                                                                           another race?       
  distxblack               1    0.000890   0.002012      0.44     0.6583                       
  distxhispanic            1    0.001291   0.001577      0.82     0.4131                       
  distxotherrace           1    -0.00299   0.002941     -1.02     0.3086                       


                                       The SYSLIN Procedure
                                Two-Stage Least Squares Estimation

                               Model                 collegexblack
                               Dependent Variable    collegexblack


                                       Analysis of Variance
 
                                             Sum of        Mean
              Source                 DF     Squares      Square    F Value    Pr > F

              Model                   7    289.5044    41.35777    1336.08    <.0001
              Error                9219    285.3711    0.030955                     
              Corrected Total      9226    574.8755                                 


                      Root MSE             0.17594    R-Square       0.50359
                      Dependent Mean       0.06676    Adj R-Sq       0.50322
                      Coeff Var          263.53779                          


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    1.94E-17   0.003593      0.00     1.0000   Intercept           
  distance                 1    -202E-20   0.000258     -0.00     1.0000   Miles from          
                                                                           respondents HS to   
                                                                           nearest 2yr college 
  black                    1    0.580126   0.008132     71.34     <.0001   Is respondent black?
  hispanic                 1    -216E-19   0.006919     -0.00     1.0000   Is respondent       
                                                                           hispanic?           
  otherrace                1    -328E-19   0.012530     -0.00     1.0000   Is respondent of    
                                                                           another race?       
  distxblack               1    -0.00622   0.000719     -8.66     <.0001                       
  distxhispanic            1    1.43E-18   0.000563      0.00     1.0000                       
  distxotherrace           1    2.51E-18   0.001051      0.00     1.0000                       


                                       The SYSLIN Procedure
                                Two-Stage Least Squares Estimation

                              Model                 collegexhispanic
                              Dependent Variable    collegexhispanic


                                       Analysis of Variance
 
                                             Sum of        Mean
              Source                 DF     Squares      Square    F Value    Pr > F

              Model                   7    326.3327    46.61895     949.38    <.0001
              Error                9219    452.6976    0.049105                     
              Corrected Total      9226    779.0302                                 


                      Root MSE             0.22160    R-Square       0.41890
                      Dependent Mean       0.09310    Adj R-Sq       0.41845
                      Coeff Var          238.02882                          


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    1.88E-17   0.004525      0.00     1.0000   Intercept           
  distance                 1    -406E-21   0.000326     -0.00     1.0000   Miles from          
                                                                           respondents HS to   
                                                                           nearest 2yr college 
  black                    1    -266E-19   0.010242     -0.00     1.0000   Is respondent black?
  hispanic                 1    0.517593   0.008714     59.39     <.0001   Is respondent       
                                                                           hispanic?           
  otherrace                1    -297E-20   0.015781     -0.00     1.0000   Is respondent of    
                                                                           another race?       
  distxblack               1    1.31E-18   0.000905      0.00     1.0000                       
  distxhispanic            1    -0.00582   0.000709     -8.21     <.0001                       
  distxotherrace           1    -241E-21   0.001323     -0.00     1.0000                       


                                       The SYSLIN Procedure
                                Two-Stage Least Squares Estimation

                             Model                 collegexotherrace
                             Dependent Variable    collegexotherrace


                                       Analysis of Variance
 
                                             Sum of        Mean
              Source                 DF     Squares      Square    F Value    Pr > F

              Model                   7    168.0322    24.00460    2119.51    <.0001
              Error                9219    104.4102    0.011326                     
              Corrected Total      9226    272.4424                                 


                      Root MSE             0.10642    R-Square       0.61676
                      Dependent Mean       0.03045    Adj R-Sq       0.61647
                      Coeff Var          349.44899                          


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    1.22E-17   0.002173      0.00     1.0000   Intercept           
  distance                 1    -713E-21   0.000156     -0.00     1.0000   Miles from          
                                                                           respondents HS to   
                                                                           nearest 2yr college 
  black                    1    -109E-19   0.004919     -0.00     1.0000   Is respondent black?
  hispanic                 1    -809E-20   0.004185     -0.00     1.0000   Is respondent       
                                                                           hispanic?           
  otherrace                1    0.704137   0.007579     92.91     <.0001   Is respondent of    
                                                                           another race?       
  distxblack               1    6.34E-19   0.000435      0.00     1.0000                       
  distxhispanic            1    6.34E-19   0.000341      0.00     1.0000                       
  distxotherrace           1    -0.01011   0.000635    -15.90     <.0001                       


                                       The SYSLIN Procedure
                                Two-Stage Least Squares Estimation

                Model                                                    register
                Dependent Variable                                       register
                Label                 Is respondent currently registered to vote?


                                       Analysis of Variance
 
                                             Sum of        Mean
              Source                 DF     Squares      Square    F Value    Pr > F

              Model                   7    10.29933    1.471333       6.74    <.0001
              Error                9219    2011.839    0.218228                     
              Corrected Total      9226    2037.394                                 


                      Root MSE             0.46715    R-Square       0.00509
                      Dependent Mean       0.67086    Adj R-Sq       0.00434
                      Coeff Var           69.63453                          


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    0.464046   0.055299      8.39     <.0001   Intercept           
  college                  1    0.358693   0.096492      3.72     0.0002   Attended junior,    
                                                                           community or 4year  
                                                                           college by 1984?    
  black                    1    0.278024   0.162701      1.71     0.0875   Is respondent black?
  hispanic                 1    0.176548   0.120819      1.46     0.1440   Is respondent       
                                                                           hispanic?           
  otherrace                1    0.174217   0.175600      0.99     0.3212   Is respondent of    
                                                                           another race?       
  collegexblack            1    -0.39859   0.302067     -1.32     0.1870                       
  collegexhispanic         1    -0.29291   0.247842     -1.18     0.2373                       
  collegexotherrace        1    -0.46335   0.284396     -1.63     0.1033                       
	

Reproduce last model (Table 10.8 page 249), dropping
the irrelevant terms. Note that the results are identical. (Not shown in the text.)

proc syslin data=dee 3sls;
   endogenous  college collegexblack collegexhispanic collegexotherrace;
   instruments distance black hispanic otherrace distxblack distxhispanic distxotherrace;
   model college = distance black hispanic otherrace distxblack distxhispanic distxotherrace;
   model collegexblack = black distxblack ;
   model collegexhispanic = hispanic distxhispanic ;
   model collegexotherrace = otherrace distxotherrace;
   model register = college black hispanic otherrace collegexblack collegexhispanic collegexotherrace;
run;

                                       The SYSLIN Procedure
                                Two-Stage Least Squares Estimation

            Model                                                              college
            Dependent Variable                                                 college
            Label                 Attended junior, community or 4year college by 1984?


                                       Analysis of Variance
 
                                             Sum of        Mean
              Source                 DF     Squares      Square    F Value    Pr > F

              Model                   7    50.20795    7.172564      29.57    <.0001
              Error                9219    2236.081    0.242551                     
              Corrected Total      9226    2286.289                                 


                      Root MSE             0.49250    R-Square       0.02196
                      Dependent Mean       0.54709    Adj R-Sq       0.02122
                      Coeff Var           90.02084                          


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    0.645183   0.010058     64.15     <.0001   Intercept           
  distance                 1    -0.00711   0.000723     -9.83     <.0001   Miles from          
                                                                           respondents HS to   
                                                                           nearest 2yr college 
  black                    1    -0.06506   0.022762     -2.86     0.0043   Is respondent black?
  hispanic                 1    -0.12759   0.019368     -6.59     <.0001   Is respondent       
                                                                           hispanic?           
  otherrace                1    0.058954   0.035074      1.68     0.0928   Is respondent of    
                                                                           another race?       
  distxblack               1    0.000890   0.002012      0.44     0.6583                       
  distxhispanic            1    0.001291   0.001577      0.82     0.4131                       
  distxotherrace           1    -0.00299   0.002941     -1.02     0.3086                       


                                       The SYSLIN Procedure
                                Two-Stage Least Squares Estimation

                               Model                 collegexblack
                               Dependent Variable    collegexblack


                                       Analysis of Variance
 
                                             Sum of        Mean
              Source                 DF     Squares      Square    F Value    Pr > F

              Model                   2    289.5044    144.7522    4678.80    <.0001
              Error                9224    285.3711    0.030938                     
              Corrected Total      9226    574.8755                                 


                      Root MSE             0.17589    R-Square       0.50359
                      Dependent Mean       0.06676    Adj R-Sq       0.50349
                      Coeff Var          263.46635                          


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    -916E-20   0.001958     -0.00     1.0000   Intercept           
  black                    1    0.580126   0.007551     76.83     <.0001   Is respondent black?
  distxblack               1    -0.00622   0.000671     -9.28     <.0001                       


                                       The SYSLIN Procedure
                                Two-Stage Least Squares Estimation

                              Model                 collegexhispanic
                              Dependent Variable    collegexhispanic


                                       Analysis of Variance
 
                                             Sum of        Mean
              Source                 DF     Squares      Square    F Value    Pr > F

              Model                   2    326.3327    163.1663    3324.62    <.0001
              Error                9224    452.6976    0.049078                     
              Corrected Total      9226    779.0302                                 


                      Root MSE             0.22154    R-Square       0.41890
                      Dependent Mean       0.09310    Adj R-Sq       0.41877
                      Coeff Var          237.96429                          


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    -643E-20   0.002577     -0.00     1.0000   Intercept           
  hispanic                 1    0.517593   0.007879     65.70     <.0001   Is respondent       
                                                                           hispanic?           
  distxhispanic            1    -0.00582   0.000630     -9.24     <.0001                       


                                       The SYSLIN Procedure
                                Two-Stage Least Squares Estimation

                             Model                 collegexotherrace
                             Dependent Variable    collegexotherrace


                                       Analysis of Variance
 
                                             Sum of        Mean
              Source                 DF     Squares      Square    F Value    Pr > F

              Model                   2    168.0322    84.01609    7422.30    <.0001
              Error                9224    104.4102    0.011319                     
              Corrected Total      9226    272.4424                                 


                      Root MSE             0.10639    R-Square       0.61676
                      Dependent Mean       0.03045    Adj R-Sq       0.61668
                      Coeff Var          349.35427                          


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    -123E-20   0.001136     -0.00     1.0000   Intercept           
  otherrace                1    0.704137   0.007347     95.84     <.0001   Is respondent of    
                                                                           another race?       
  distxotherrace           1    -0.01011   0.000616    -16.41     <.0001                       


                                       The SYSLIN Procedure
                                Two-Stage Least Squares Estimation

                Model                                                    register
                Dependent Variable                                       register
                Label                 Is respondent currently registered to vote?


                                       Analysis of Variance
 
                                             Sum of        Mean
              Source                 DF     Squares      Square    F Value    Pr > F

              Model                   7    10.29933    1.471333       6.74    <.0001
              Error                9219    2011.839    0.218228                     
              Corrected Total      9226    2037.394                                 


                      Root MSE             0.46715    R-Square       0.00509
                      Dependent Mean       0.67086    Adj R-Sq       0.00434
                      Coeff Var           69.63453                          


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    0.464046   0.055299      8.39     <.0001   Intercept           
  college                  1    0.358693   0.096492      3.72     0.0002   Attended junior,    
                                                                           community or 4year  
                                                                           college by 1984?    
  black                    1    0.278024   0.162701      1.71     0.0875   Is respondent black?
  hispanic                 1    0.176548   0.120819      1.46     0.1440   Is respondent       
                                                                           hispanic?           
  otherrace                1    0.174217   0.175600      0.99     0.3212   Is respondent of    
                                                                           another race?       
  collegexblack            1    -0.39859   0.302067     -1.32     0.1870                       
  collegexhispanic         1    -0.29291   0.247842     -1.18     0.2373                       
  collegexotherrace        1    -0.46335   0.284396     -1.63     0.1033                       


                                       The SYSLIN Procedure
                               Three-Stage Least Squares Estimation

                                      Cross Model Covariance
 
                       college   collegexblack   collegexhispanic   collegexotherrace   register

  college             0.242551        0.030946           0.049092            0.011322   -.011576
  collegexblack       0.030946        0.030938           0.000000            -.000000   0.006014
  collegexhispanic    0.049092        0.000000           0.049078            0.000000   0.005229
  collegexotherrace   0.011322        -.000000           0.000000            0.011319   0.002175
  register            -.011576        0.006014           0.005229            0.002175   0.218228


                                     Cross Model Correlation
 
                       college   collegexblack   collegexhispanic   collegexotherrace   register

  college              1.00000         0.35724            0.44995             0.21609   -0.05031
  collegexblack        0.35724         1.00000            0.00000            -0.00000    0.07319
  collegexhispanic     0.44995         0.00000            1.00000             0.00000    0.05053
  collegexotherrace    0.21609        -0.00000            0.00000             1.00000    0.04376
  register            -0.05031         0.07319            0.05053             0.04376    1.00000


                                 Cross Model Inverse Correlation
 
                       college   collegexblack   collegexhispanic   collegexotherrace   register

  college              1.63583        -0.59752           -0.74510            -0.36134    0.17950
  collegexblack       -0.59752         1.22367            0.27590             0.13522   -0.13949
  collegexhispanic    -0.74510         0.27590            1.34197             0.16682   -0.13279
  collegexotherrace   -0.36134         0.13522            0.16682             1.08175   -0.08385
  register             0.17950        -0.13949           -0.13279            -0.08385    1.02962


                                  Cross Model Inverse Covariance
 
                       college   collegexblack   collegexhispanic   collegexotherrace   register

  college              6.74425         -6.8977            -6.8292             -6.8960    0.78021
  collegexblack       -6.89775         39.5524             7.0805              7.2258   -1.69760
  collegexhispanic    -6.82921          7.0805            27.3434              7.0776   -1.28312
  collegexotherrace   -6.89600          7.2258             7.0776             95.5659   -1.68704
  register             0.78021         -1.6976            -1.2831             -1.6870    4.71810


                              System Weighted MSE            1.0187
                              Degrees of freedom              46110
                              System Weighted R-Square       0.4339


                                       The SYSLIN Procedure
                               Three-Stage Least Squares Estimation

            Model                                                              college
            Dependent Variable                                                 college
            Label                 Attended junior, community or 4year college by 1984?


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    0.645183   0.008650     74.59     <.0001   Intercept           
  distance                 1    -0.00711   0.000571    -12.45     <.0001   Miles from          
                                                                           respondents HS to   
                                                                           nearest 2yr college 
  black                    1    -0.06506   0.019493     -3.34     0.0008   Is respondent black?
  hispanic                 1    -0.12759   0.017201     -7.42     <.0001   Is respondent       
                                                                           hispanic?           
  otherrace                1    0.058954   0.028648      2.06     0.0396   Is respondent of    
                                                                           another race?       
  distxblack               1    0.000890   0.001724      0.52     0.6057                       
  distxhispanic            1    0.001291   0.001395      0.92     0.3550                       
  distxotherrace           1    -0.00299   0.002402     -1.25     0.2126                       


                                       The SYSLIN Procedure
                               Three-Stage Least Squares Estimation

                               Model                 collegexblack
                               Dependent Variable    collegexblack


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1     2.4E-17   0.001958      0.00     1.0000   Intercept           
  black                    1    0.580126   0.007551     76.83     <.0001   Is respondent black?
  distxblack               1    -0.00622   0.000671     -9.28     <.0001                       


                                       The SYSLIN Procedure
                               Three-Stage Least Squares Estimation

                              Model                 collegexhispanic
                              Dependent Variable    collegexhispanic


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    2.64E-17   0.002577      0.00     1.0000   Intercept           
  hispanic                 1    0.517593   0.007879     65.70     <.0001   Is respondent       
                                                                           hispanic?           
  distxhispanic            1    -0.00582   0.000630     -9.24     <.0001                       


                                       The SYSLIN Procedure
                               Three-Stage Least Squares Estimation

                             Model                 collegexotherrace
                             Dependent Variable    collegexotherrace


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    1.01E-17   0.001136      0.00     1.0000   Intercept           
  otherrace                1    0.704137   0.007347     95.84     <.0001   Is respondent of    
                                                                           another race?       
  distxotherrace           1    -0.01011   0.000616    -16.41     <.0001                       


                                       The SYSLIN Procedure
                               Three-Stage Least Squares Estimation

                Model                                                    register
                Dependent Variable                                       register
                Label                 Is respondent currently registered to vote?


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    0.464046   0.055030      8.43     <.0001   Intercept           
  college                  1    0.358693   0.096017      3.74     0.0002   Attended junior,    
                                                                           community or 4year  
                                                                           college by 1984?    
  black                    1    0.278024   0.162287      1.71     0.0867   Is respondent black?
  hispanic                 1    0.176548   0.120347      1.47     0.1424   Is respondent       
                                                                           hispanic?           
  otherrace                1    0.174217   0.174887      1.00     0.3192   Is respondent of    
                                                                           another race?       
  collegexblack            1    -0.39859   0.301308     -1.32     0.1859                       
  collegexhispanic         1    -0.29291   0.246891     -1.19     0.2355                       
  collegexotherrace        1    -0.46335   0.283238     -1.64     0.1019                       
	

A model similar to the last two (both of which replicate Table 10.8 page 249) estimated using
simultaneous equations, dropping
the irrelevant terms and non-significant variables from the model. Note that the results are very similar, but
not identical. (Not shown in the text.)

proc syslin data=dee 3sls;
   endogenous  college collegexblack collegexhispanic collegexotherrace;
   instruments distance black hispanic otherrace distxblack distxhispanic distxotherrace;
   model college = distance black hispanic otherrace;
   model collegexblack = black distxblack ;
   model collegexhispanic = hispanic distxhispanic ;
   model collegexotherrace = otherrace distxotherrace;
   model register = college black hispanic otherrace collegexblack collegexhispanic collegexotherrace;
run;


                                       The SYSLIN Procedure
                                Two-Stage Least Squares Estimation

            Model                                                              college
            Dependent Variable                                                 college
            Label                 Attended junior, community or 4year college by 1984?


                                       Analysis of Variance
 
                                             Sum of        Mean
              Source                 DF     Squares      Square    F Value    Pr > F

              Model                   4    49.70516    12.42629      51.24    <.0001
              Error                9222    2236.584    0.242527                     
              Corrected Total      9226    2286.289                                 


                      Root MSE             0.49247    R-Square       0.02174
                      Dependent Mean       0.54709    Adj R-Sq       0.02132
                      Coeff Var           90.01632                          


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    0.643146   0.009053     71.04     <.0001   Intercept           
  distance                 1    -0.00692   0.000595    -11.64     <.0001   Miles from          
                                                                           respondents HS to   
                                                                           nearest 2yr college 
  black                    1    -0.05766   0.015959     -3.61     0.0003   Is respondent black?
  hispanic                 1    -0.11621   0.013257     -8.77     <.0001   Is respondent       
                                                                           hispanic?           
  otherrace                1    0.033708   0.024010      1.40     0.1604   Is respondent of    
                                                                           another race?       


                                       The SYSLIN Procedure
                                Two-Stage Least Squares Estimation

                               Model                 collegexblack
                               Dependent Variable    collegexblack


                                       Analysis of Variance
 
                                             Sum of        Mean
              Source                 DF     Squares      Square    F Value    Pr > F

              Model                   2    289.5044    144.7522    4678.80    <.0001
              Error                9224    285.3711    0.030938                     
              Corrected Total      9226    574.8755                                 


                      Root MSE             0.17589    R-Square       0.50359
                      Dependent Mean       0.06676    Adj R-Sq       0.50349
                      Coeff Var          263.46635                          


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    -916E-20   0.001958     -0.00     1.0000   Intercept           
  black                    1    0.580126   0.007551     76.83     <.0001   Is respondent black?
  distxblack               1    -0.00622   0.000671     -9.28     <.0001                       


                                       The SYSLIN Procedure
                                Two-Stage Least Squares Estimation

                              Model                 collegexhispanic
                              Dependent Variable    collegexhispanic


                                       Analysis of Variance
 
                                             Sum of        Mean
              Source                 DF     Squares      Square    F Value    Pr > F

              Model                   2    326.3327    163.1663    3324.62    <.0001
              Error                9224    452.6976    0.049078                     
              Corrected Total      9226    779.0302                                 


                      Root MSE             0.22154    R-Square       0.41890
                      Dependent Mean       0.09310    Adj R-Sq       0.41877
                      Coeff Var          237.96429                          


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    -643E-20   0.002577     -0.00     1.0000   Intercept           
  hispanic                 1    0.517593   0.007879     65.70     <.0001   Is respondent       
                                                                           hispanic?           
  distxhispanic            1    -0.00582   0.000630     -9.24     <.0001                       


                                       The SYSLIN Procedure
                                Two-Stage Least Squares Estimation

                             Model                 collegexotherrace
                             Dependent Variable    collegexotherrace


                                       Analysis of Variance
 
                                             Sum of        Mean
              Source                 DF     Squares      Square    F Value    Pr > F

              Model                   2    168.0322    84.01609    7422.30    <.0001
              Error                9224    104.4102    0.011319                     
              Corrected Total      9226    272.4424                                 


                      Root MSE             0.10639    R-Square       0.61676
                      Dependent Mean       0.03045    Adj R-Sq       0.61668
                      Coeff Var          349.35427                          


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    -123E-20   0.001136     -0.00     1.0000   Intercept           
  otherrace                1    0.704137   0.007347     95.84     <.0001   Is respondent of    
                                                                           another race?       
  distxotherrace           1    -0.01011   0.000616    -16.41     <.0001                       


                                       The SYSLIN Procedure
                                Two-Stage Least Squares Estimation

                Model                                                    register
                Dependent Variable                                       register
                Label                 Is respondent currently registered to vote?


                                       Analysis of Variance
 
                                             Sum of        Mean
              Source                 DF     Squares      Square    F Value    Pr > F

              Model                   7    10.29933    1.471333       6.74    <.0001
              Error                9219    2011.839    0.218228                     
              Corrected Total      9226    2037.394                                 


                      Root MSE             0.46715    R-Square       0.00509
                      Dependent Mean       0.67086    Adj R-Sq       0.00434
                      Coeff Var           69.63453                          


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    0.464046   0.055299      8.39     <.0001   Intercept           
  college                  1    0.358693   0.096492      3.72     0.0002   Attended junior,    
                                                                           community or 4year  
                                                                           college by 1984?    
  black                    1    0.278024   0.162701      1.71     0.0875   Is respondent black?
  hispanic                 1    0.176548   0.120819      1.46     0.1440   Is respondent       
                                                                           hispanic?           
  otherrace                1    0.174217   0.175600      0.99     0.3212   Is respondent of    
                                                                           another race?       
  collegexblack            1    -0.39859   0.302067     -1.32     0.1870                       
  collegexhispanic         1    -0.29291   0.247842     -1.18     0.2373                       
  collegexotherrace        1    -0.46335   0.284396     -1.63     0.1033                       


                                       The SYSLIN Procedure
                               Three-Stage Least Squares Estimation

                                      Cross Model Covariance
 
                       college   collegexblack   collegexhispanic   collegexotherrace   register

  college             0.242527        0.030941           0.049084            0.011321   -.011574
  collegexblack       0.030941        0.030938           0.000000            -.000000   0.006014
  collegexhispanic    0.049084        0.000000           0.049078            0.000000   0.005229
  collegexotherrace   0.011321        -.000000           0.000000            0.011319   0.002175
  register            -.011574        0.006014           0.005229            0.002175   0.218228


                                     Cross Model Correlation
 
                       college   collegexblack   collegexhispanic   collegexotherrace   register

  college              1.00000         0.35720            0.44990             0.21606   -0.05031
  collegexblack        0.35720         1.00000            0.00000            -0.00000    0.07319
  collegexhispanic     0.44990         0.00000            1.00000             0.00000    0.05053
  collegexotherrace    0.21606        -0.00000            0.00000             1.00000    0.04376
  register            -0.05031         0.07319            0.05053             0.04376    1.00000


                                 Cross Model Inverse Correlation
 
                       college   collegexblack   collegexhispanic   collegexotherrace   register

  college              1.63559        -0.59737           -0.74491            -0.36124    0.17946
  collegexblack       -0.59737         1.22359            0.27580             0.13517   -0.13946
  collegexhispanic    -0.74491         0.27580            1.34184             0.16676   -0.13276
  collegexotherrace   -0.36124         0.13517            0.16676             1.08172   -0.08383
  register             0.17946        -0.13946           -0.13276            -0.08383    1.02961


                                  Cross Model Inverse Covariance
 
                       college   collegexblack   collegexhispanic   collegexotherrace   register

  college              6.74396         -6.8963            -6.8278             -6.8946    0.78005
  collegexblack       -6.89633         39.5499             7.0779              7.2232   -1.69731
  collegexhispanic    -6.82781          7.0779            27.3409              7.0751   -1.28283
  collegexotherrace   -6.89459          7.2232             7.0751             95.5633   -1.68675
  register             0.78005         -1.6973            -1.2828             -1.6868    4.71807


                              System Weighted MSE            1.0187
                              Degrees of freedom              46113
                              System Weighted R-Square       0.4338


                                       The SYSLIN Procedure
                               Three-Stage Least Squares Estimation

            Model                                                              college
            Dependent Variable                                                 college
            Label                 Attended junior, community or 4year college by 1984?


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    0.643723   0.008035     80.11     <.0001   Intercept           
  distance                 1    -0.00697   0.000485    -14.37     <.0001   Miles from          
                                                                           respondents HS to   
                                                                           nearest 2yr college 
  black                    1    -0.05782   0.013765     -4.20     <.0001   Is respondent black?
  hispanic                 1    -0.11633   0.011958     -9.73     <.0001   Is respondent       
                                                                           hispanic?           
  otherrace                1    0.033595   0.019636      1.71     0.0871   Is respondent of    
                                                                           another race?       


                                       The SYSLIN Procedure
                               Three-Stage Least Squares Estimation

                               Model                 collegexblack
                               Dependent Variable    collegexblack


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    -154E-19   0.001958     -0.00     1.0000   Intercept           
  black                    1    0.581107   0.007275     79.88     <.0001   Is respondent black?
  distxblack               1    -0.00635   0.000616    -10.30     <.0001                       


                                       The SYSLIN Procedure
                               Three-Stage Least Squares Estimation

                              Model                 collegexhispanic
                              Dependent Variable    collegexhispanic


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    1.34E-17   0.002577      0.00     1.0000   Intercept           
  hispanic                 1    0.519995   0.007487     69.45     <.0001   Is respondent       
                                                                           hispanic?           
  distxhispanic            1    -0.00610   0.000560    -10.89     <.0001                       


                                       The SYSLIN Procedure
                               Three-Stage Least Squares Estimation

                             Model                 collegexotherrace
                             Dependent Variable    collegexotherrace


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    6.98E-18   0.001136      0.00     1.0000   Intercept           
  otherrace                1    0.702269   0.007220     97.27     <.0001   Is respondent of    
                                                                           another race?       
  distxotherrace           1    -0.00989   0.000595    -16.62     <.0001                       


                                       The SYSLIN Procedure
                               Three-Stage Least Squares Estimation

                Model                                                    register
                Dependent Variable                                       register
                Label                 Is respondent currently registered to vote?


                                       Parameter Estimates
 
                               Parameter   Standard                        Variable
  Variable                DF    Estimate      Error   t Value   Pr > |t|   Label

  Intercept                1    0.462228   0.054885      8.42     <.0001   Intercept           
  college                  1    0.361883   0.095762      3.78     0.0002   Attended junior,    
                                                                           community or 4year  
                                                                           college by 1984?    
  black                    1    0.286554   0.161474      1.77     0.0760   Is respondent black?
  hispanic                 1    0.187519   0.119711      1.57     0.1173   Is respondent       
                                                                           hispanic?           
  otherrace                1    0.149163   0.173587      0.86     0.3902   Is respondent of    
                                                                           another race?       
  collegexblack            1    -0.41439   0.299796     -1.38     0.1669                       
  collegexhispanic         1    -0.31565   0.245606     -1.29     0.1988                       
  collegexotherrace        1    -0.42303   0.281100     -1.50     0.1324                      
  

The analyses in shown in Table 10.9 includes a variable that is restricted, so these
analyses cannot be reproduced using the available dataset.