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Design and Analysis, Fourth Edition, by Keppel and Wickens Chapter 23: Within-Subject and Mixed Design | SAS Textbook Examples

Data from table 23.3, page 515

data table23_3;
input s a b c y @@;
datalines;
1  1 1 1 11		1  1 1 2 5		1  1 1 3 3
2  1 1 1 12		2  1 1 2 10		2  1 1 3 5
3  1 2 1 17		3  1 2 2 11		3  1 2 3 11
4  1 2 1 18		4  1 2 2 16		4  1 2 3 13
5  2 1 1 20		5  2 1 2 14		5  2 1 3 13
6  2 1 1 12		6  2 1 2 10		6  2 1 3 9
7  2 2 1 16		7  2 2 2 10		7  2 2 3 10
8  2 2 1 20		8  2 2 2 18		8  2 2 3 14
9  3 1 1 23		9  3 1 2 17		9  3 1 3 18
10 3 1 1 22		10 3 1 2 19		10 3 1 3 22
11 3 2 1 14		11 3 2 2 8		11 3 2 3 8
12 3 2 1 18		12 3 2 2 16		12 3 2 3 12
; 
run;

data table23_3w;
input s a b c1 c2 c3;
datalines;
1  1 1 11  5  3
2  1 1 12 10  5
3  1 2 17 11 11
4  1 2 18 16 13
5  2 1 20 14 13
6  2 1 12 10  9
7  2 2 16 10 10
8  2 2 20 18 14
9  3 1 23 17 18
10 3 1 22 19 22
11 3 2 14  8  8
12 3 2 18 16 12
; 
run;

Table 23.3, page 515. Analysis of variance of mixed three-way factorial
design with two between-subject factors (a and b)  and one within-subject
factor (factor c)

NOTE: proc glm on the narrow data set in a A*B*(C*S) design is more
complex than either proc mixed or proc glm on the wide data set.
The complexities arises since we have to specify the nesting () of 
factors and define the tests for between and within subject tests.
However, in a A*(B*C*S) design (the next problem) proc glm is the easiest
way the model the between and within subject factors, but it is still complex. Table 23.2 and page 512-514 of Keppel discuss the correct
error terms with respect the design.

proc glm data = table23_3;
class s a b c;
model y = a b a*b s(a*b) c a*c b*c a*b*c c*s(a*b)/ss3;
test h = a b a*b e = s(a*b); 
test h = c a*c b*c a*b*c e =c*s(a*b);
run; quit;
The GLM Procedure

              Class Level Information
Class         Levels    Values
s                 12    1 2 3 4 5 6 7 8 9 10 11 12
a                  3    1 2 3
b                  2    1 2
c                  3    1 2 3

Number of observations    36

Dependent Variable: y
                                        Sum of
Source                      DF         Squares     Mean Square    F Value    Pr > F
Model                       35     882.7500000      25.2214286        .       .
Error                        0       0.0000000        .
Corrected Total             35     882.7500000

R-Square     Coeff Var      Root MSE        y Mean
1.000000           .               .      13.75000

Source                      DF     Type III SS     Mean Square    F Value    Pr > F
a                            2     176.1666667      88.0833333        .       .
b                            1       0.6944444       0.6944444        .       .
a*b                          2     309.7222222     154.8611111        .       .
s(a*b)                       6     153.5000000      25.5833333        .       .
c                            2     191.1666667      95.5833333        .       .
a*c                          4       7.6666667       1.9166667        .       .
b*c                          2       1.7222222       0.8611111        .       .
a*b*c                        4      11.1111111       2.7777778        .       .
s*c(a*b)                    12      31.0000000       2.5833333        .       .

       Tests of Hypotheses Using the Type III MS for s(a*b) as an Error Term
Source                      DF     Type III SS     Mean Square    F Value    Pr > F
a                            2     176.1666667      88.0833333       3.44    0.1009
b                            1       0.6944444       0.6944444       0.03    0.8745
a*b                          2     309.7222222     154.8611111       6.05    0.0364

      Tests of Hypotheses Using the Type III MS for s*c(a*b) as an Error Term
Source                      DF     Type III SS     Mean Square    F Value    Pr > F
c                            2     191.1666667      95.5833333      37.00    <.0001
a*c                          4       7.6666667       1.9166667       0.74    0.5815
b*c                          2       1.7222222       0.8611111       0.33    0.7230
a*b*c                        4      11.1111111       2.7777778       1.08    0.4111
proc glm data = table23_3w;
class a b;
model c1 c2 c3 = a|b;
repeated c 3;
run; quit;

[c-level output omitted]

Repeated Measures Analysis of Variance

       Repeated Measures Level Information
Dependent Variable          c1       c2       c3
        Level of c           1        2        3

 Manova Test Criteria and Exact F Statistics for the Hypothesis of no c Effect
                        H = Type III SSCP Matrix for c
                             E = Error SSCP Matrix
                              S=1    M=0    N=1.5
Statistic                        Value    F Value    Num DF    Den DF    Pr > F
Wilks' Lambda               0.05654871      41.71         2         5    0.0008
Pillai's Trace              0.94345129      41.71         2         5    0.0008
Hotelling-Lawley Trace     16.68386817      41.71         2         5    0.0008
Roy's Greatest Root        16.68386817      41.71         2         5    0.0008

 Manova Test Criteria and F Approximations for the Hypothesis of no c*a Effect
                       H = Type III SSCP Matrix for c*a
                             E = Error SSCP Matrix
                            S=2    M=-0.5    N=1.5
Statistic                        Value    F Value    Num DF    Den DF    Pr > F
Wilks' Lambda               0.53462133       0.92         4        10    0.4899
Pillai's Trace              0.46568779       0.91         4        12    0.4886
Hotelling-Lawley Trace      0.86990460       1.07         4    5.1429    0.4578
Roy's Greatest Root         0.86923942       2.61         2         6    0.1531
NOTE: F Statistic for Roy's Greatest Root is an upper bound.
NOTE: F Statistic for Wilks' Lambda is exact.

Manova Test Criteria and Exact F Statistics for the Hypothesis of no c*b Effect
                       H = Type III SSCP Matrix for c*b
                             E = Error SSCP Matrix
                              S=1    M=0    N=1.5
Statistic                        Value    F Value    Num DF    Den DF    Pr > F
Wilks' Lambda               0.83885049       0.48         2         5    0.6445
Pillai's Trace              0.16114951       0.48         2         5    0.6445
Hotelling-Lawley Trace      0.19210755       0.48         2         5    0.6445
Roy's Greatest Root         0.19210755       0.48         2         5    0.6445
Manova Test Criteria and F Approximations for the Hypothesis of no c*a*b Effect
                      H = Type III SSCP Matrix for c*a*b
                             E = Error SSCP Matrix
                            S=2    M=-0.5    N=1.5
Statistic                        Value    F Value    Num DF    Den DF    Pr > F
Wilks' Lambda               0.44083349       1.27         4        10    0.3458
Pillai's Trace              0.55974001       1.17         4        12    0.3737
Hotelling-Lawley Trace      1.26712923       1.56         4    5.1429    0.3135
Roy's Greatest Root         1.26610170       3.80         2         6    0.0859
NOTE: F Statistic for Roy's Greatest Root is an upper bound.
NOTE: F Statistic for Wilks' Lambda is exact.
Tests of Hypotheses for Between Subjects Effects
Source                      DF     Type III SS     Mean Square    F Value    Pr > F
a                            2     176.1666667      88.0833333       3.44    0.1009
b                            1       0.6944444       0.6944444       0.03    0.8745
a*b                          2     309.7222222     154.8611111       6.05    0.0364
Error                        6     153.5000000      25.5833333
Univariate Tests of Hypotheses for Within Subject Effects
                                                                                    Adj Pr > F
Source                     DF    Type III SS    Mean Square   F Value   Pr > F    G - G    H - F
c                           2    191.1666667     95.5833333     37.00   <.0001   <.0001   <.0001
c*a                         4      7.6666667      1.9166667      0.74   0.5815   0.5636   0.5815
c*b                         2      1.7222222      0.8611111      0.33   0.7230   0.6866   0.7230
c*a*b                       4     11.1111111      2.7777778      1.08   0.4111   0.4090   0.4111
Error(c)                   12     31.0000000      2.5833333

Greenhouse-Geisser Epsilon    0.8332
Huynh-Feldt Epsilon           2.076
proc mixed data = table23_3;
class s a b c;
model y = a|b|c;
repeated/ subject = s type = cs;
run; quit;
The Mixed Procedure

                  Model Information
Data Set                     WORK.TABLE23_3
Dependent Variable           y
Covariance Structure         Compound Symmetry
Subject Effect               s
Estimation Method            REML
Residual Variance Method     Profile
Fixed Effects SE Method      Model-Based
Degrees of Freedom Method    Between-Within

             Class Level Information
Class    Levels    Values
s            12    1 2 3 4 5 6 7 8 9 10 11 12
a             3    1 2 3
b             2    1 2
c             3    1 2 3

            Dimensions
Covariance Parameters             2
Columns in X                     48
Columns in Z                      0
Subjects                         12
Max Obs Per Subject               3
Observations Used                36
Observations Not Used             0
Total Observations               36

                     Iteration History
Iteration    Evaluations    -2 Res Log Like       Criterion
        0              1       105.44943515
        1              1        94.39904969      0.00000000
                   Convergence criteria met.

 Covariance Parameter Estimates
Cov Parm     Subject    Estimate
CS           s            7.6667
Residual                  2.5833

           Fit Statistics
-2 Res Log Likelihood            94.4
AIC (smaller is better)          98.4
AICC (smaller is better)         99.2
BIC (smaller is better)          99.4

  Null Model Likelihood Ratio Test
    DF    Chi-Square      Pr > ChiSq
     1         11.05          0.0009

        Type 3 Tests of Fixed Effects
              Num     Den
Effect         DF      DF    F Value    Pr > F
a               2       6       3.44    0.1009
b               1       6       0.03    0.8745
a*b             2       6       6.05    0.0364
c               2      12      37.00    <.0001
a*c             4      12       0.74    0.5815
b*c             2      12       0.33    0.7230
a*b*c           4      12       1.08    0.4111

Data from table 23.4, page 517

data table23_4;
input s a b c y @@;
datalines;
1 1 1 1 1	1 1 2 1 1	1 1 3 1 2
1 1 1 2 1	1 1 2 2 3	1 1 3 2 2
1 1 1 3 2	1 1 2 3 4	1 1 3 3 2
2 1 1 1 2	2 1 2 1 3	2 1 3 1 3
2 1 1 2 2	2 1 2 2 4	2 1 3 2 4
2 1 1 3 3	2 1 2 3 5	2 1 3 3 4
3 1 1 1 1	3 1 2 1 2	3 1 3 1 3
3 1 1 2 3	3 1 2 2 3	3 1 3 2 5
3 1 1 3 2	3 1 2 3 5	3 1 3 3 5
4 2 1 1 2	4 2 2 1 1	4 2 3 1 1
4 2 1 2 2	4 2 2 2 2	4 2 3 2 2
4 2 1 3 3	4 2 2 3 3	4 2 3 3 2
5 2 1 1 3	5 2 2 1 2	5 2 3 1 3
5 2 1 2 3	5 2 2 2 4	5 2 3 2 3
5 2 1 3 5	5 2 2 3 5	5 2 3 3 4
6 2 1 1 1	6 2 2 1 2	6 2 3 1 1
6 2 1 2 2	6 2 2 2 3	6 2 3 2 3
6 2 1 3 1	6 2 2 3 3	6 2 3 3 2
; 
run;

Table 23.4, page 517. Analysis of variance of a mixed three-way factorial
design with one between-subject factor (A) and two within-subject factors (B and
C)

proc glm data = table23_4;
class s a b c;
model y = a|b|c|s(a)/ss3;
test h = a e = s(a);
test h = b a*b e = b*s(a);
test h = c a*c e = c*s(a);
test h = b*c a*b*c e = b*c*s(a);
run; quit;
The GLM Procedure

Dependent Variable: y
                                        Sum of
Source                      DF         Squares     Mean Square    F Value    Pr > F
Model                       53     77.64814815      1.46505940        .       .
Error                        0      0.00000000       .
Corrected Total             53     77.64814815

R-Square     Coeff Var      Root MSE        y Mean
1.000000           .               .      2.685185

Source                      DF     Type III SS     Mean Square    F Value    Pr > F
a                            1      1.50000000      1.50000000        .       .
b                            2      7.70370370      3.85185185        .       .
a*b                          2      5.77777778      2.88888889        .       .
c                            2     19.37037037      9.68518519        .       .
a*c                          2      0.11111111      0.05555556        .       .
b*c                          4      4.07407407      1.01851852        .       .
a*b*c                        4      0.44444444      0.11111111        .       .
s(a)                         4     24.37037037      6.09259259        .       .
s*b(a)                       8      5.62962963      0.70370370        .       .
s*c(a)                       8      4.29629630      0.53703704        .       .
s*b*c(a)                    16      4.37037037      0.27314815        .       .

        Tests of Hypotheses Using the Type III MS for s(a) as an Error Term
Source                      DF     Type III SS     Mean Square    F Value    Pr > F
a                            1      1.50000000      1.50000000       0.25    0.6458

       Tests of Hypotheses Using the Type III MS for s*b(a) as an Error Term
Source                      DF     Type III SS     Mean Square    F Value    Pr > F
b                            2      7.70370370      3.85185185       5.47    0.0318
a*b                          2      5.77777778      2.88888889       4.11    0.0593

       Tests of Hypotheses Using the Type III MS for s*c(a) as an Error Term
Source                      DF     Type III SS     Mean Square    F Value    Pr > F
c                            2     19.37037037      9.68518519      18.03    0.0011
a*c                          2      0.11111111      0.05555556       0.10    0.9029

      Tests of Hypotheses Using the Type III MS for s*b*c(a) as an Error Term
Source                      DF     Type III SS     Mean Square    F Value    Pr > F
b*c                          4      4.07407407      1.01851852       3.73    0.0250
a*b*c                        4      0.44444444      0.11111111       0.41    0.8011

Table 23.10, page 526. Analysis of the between-subjects simple interaction
A*B at c=3.

NOTE: Evaluating the design at a specific level of a within-subject factor
reduces the design to a  two-factor between-subject design.

proc glm data = table23_3;
where c =3;
class a b ;
model y = a|b /ss3;
run; quit;
The GLM Procedure

   Class Level Information
Class         Levels    Values
a                  3    1 2 3
b                  2    1 2

Number of observations    12
Dependent Variable: y
                                        Sum of
Source                      DF         Squares     Mean Square    F Value    Pr > F
Model                        5     263.0000000      52.6000000       8.77    0.0099
Error                        6      36.0000000       6.0000000
Corrected Total             11     299.0000000

R-Square     Coeff Var      Root MSE        y Mean
0.879599      21.29991      2.449490      11.50000

Source                      DF     Type III SS     Mean Square    F Value    Pr > F
a                            2      98.0000000      49.0000000       8.17    0.0194
b                            1       0.3333333       0.3333333       0.06    0.8215
a*b                          2     164.6666667      82.3333333      13.72    0.0058
proc glm data = table23_3w;
class a b;
model c3 = a|b /ss3;
run; quit;
The GLM Procedure

   Class Level Information
Class         Levels    Values
a                  3    1 2 3
b                  2    1 2

Number of observations    12

Dependent Variable: c3
                                        Sum of
Source                      DF         Squares     Mean Square    F Value    Pr > F
Model                        5     263.0000000      52.6000000       8.77    0.0099
Error                        6      36.0000000       6.0000000
Corrected Total             11     299.0000000

R-Square     Coeff Var      Root MSE       c3 Mean
0.879599      21.29991      2.449490      11.50000

Source                      DF     Type III SS     Mean Square    F Value    Pr > F
a                            2      98.0000000      49.0000000       8.17    0.0194
b                            1       0.3333333       0.3333333       0.06    0.8215
a*b                          2     164.6666667      82.3333333      13.72    0.0058
proc mixed data = table23_3;
where c = 3;
class s a b ;
model y = a|b;
repeated/ subject = s type = cs;
run; quit;
The Mixed Procedure

                  Model Information
Data Set                     WORK.TABLE23_3
Dependent Variable           y
Covariance Structure         Compound Symmetry
Subject Effect               s
Estimation Method            REML
Residual Variance Method     Profile
Fixed Effects SE Method      Model-Based
Degrees of Freedom Method    Between-Within

             Class Level Information
Class    Levels    Values
s            12    1 2 3 4 5 6 7 8 9 10 11 12
a             3    1 2 3
b             2    1 2

            Dimensions
Covariance Parameters             2
Columns in X                     12
Columns in Z                      0
Subjects                         12
Max Obs Per Subject               1
Observations Used                12
Observations Not Used             0
Total Observations               12

                     Iteration History
Iteration    Evaluations    -2 Res Log Like       Criterion
        0              1        31.93670230
        1              1        31.93670230      0.00000000
   Convergence criteria met but final hessian is not positive
                           definite.

 Covariance Parameter Estimates
Cov Parm     Subject    Estimate
CS           s            5.1429
Residual                  0.8571

           Fit Statistics
-2 Res Log Likelihood            31.9
AIC (smaller is better)          35.9
AICC (smaller is better)         39.9
BIC (smaller is better)          36.9

  Null Model Likelihood Ratio Test
    DF    Chi-Square      Pr > ChiSq
     1          0.00          1.0000

        Type 3 Tests of Fixed Effects
              Num     Den
Effect         DF      DF    F Value    Pr > F

a               2       6       8.17    0.0194
b               1       6       0.06    0.8215
a*b             2       6      13.72    0.0058

Table 23.12, page 528. Simple effects of factor B and C for female subjects
from the data in Table 23.4 using only the restricted error terms.

NOTE: Restricting the design to one level of the between subject factor
reduces the design to a two-factor within-subject design.

proc glm data = table23_4;
where a = 1;
class s b c;
model y = b|c|s/ss3;
test h = b e = b*s;
test h = c e = c*s;
test h = b*c e = s*b*c ;
run;quit;
The GLM Procedure

Dependent Variable: y
                                        Sum of
Source                      DF         Squares     Mean Square    F Value    Pr > F
Model                       26     43.40740741      1.66951567        .       .
Error                        0      0.00000000       .
Corrected Total             26     43.40740741

R-Square     Coeff Var      Root MSE        y Mean
1.000000           .               .      2.851852

Source                      DF     Type III SS     Mean Square    F Value    Pr > F
b                            2     12.51851852      6.25925926        .       .
c                            2     11.18518519      5.59259259        .       .
b*c                          4      3.03703704      0.75925926        .       .
s                            2      9.85185185      4.92592593        .       .
s*b                          4      3.03703704      0.75925926        .       .
s*c                          4      1.03703704      0.25925926        .       .
s*b*c                        8      2.74074074      0.34259259        .       .

        Tests of Hypotheses Using the Type III MS for s*b as an Error Term
Source                      DF     Type III SS     Mean Square    F Value    Pr > F
b                            2     12.51851852      6.25925926       8.24    0.0381

        Tests of Hypotheses Using the Type III MS for s*c as an Error Term
Source                      DF     Type III SS     Mean Square    F Value    Pr > F
c                            2     11.18518519      5.59259259      21.57    0.0072

       Tests of Hypotheses Using the Type III MS for s*b*c as an Error Term
Source                      DF     Type III SS     Mean Square    F Value    Pr > F
b*c                          4      3.03703704      0.75925926       2.22    0.1571