Suppose you had a file with 25 observations that had a variable identifying the observations called id and you had information about the observation, here we just have age. DATA…
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Credits This page was developed and written by Karla Lindquist, Senior Statistician in the Division of Geriatrics at UCSF.  We are very grateful to Karla for taking the time to…
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Reading an Excel file into SAS Suppose that you have an Excel spreadsheet called https://stats.idre.ucla.edu/wp-content/uploads/2016/02/auto.xlsx. The data for this spreadsheet are shown below. MAKE MPG WEIGHT PRICE AMC Concord 22…
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After running a logistic model with multiple predictors or an interaction, you may wish to be able to see predicted values with confidence intervals for different combinations of predictors.  This…
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Section 12.1 Nonnormally Distributed Errors Figure 12.1 (a) and (b) on page 297 and using data file ornstein. data ornstein_co; /*Dummy coding: baseline is ‘CAN’ for nation and ‘MAN’ for…
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This page contains the data files for the book Applied Regression Analysis, Linear Models, and Related methods by John Fox.  We are very grateful to Professor Fox for granting us…
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/* Education Expenditure data, table 7.3, p. 189 */ data p189; length state $ 2 ; input State Y X1 X2 X3 Region ; label x1 = ‘Income’ x2 =…
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Examples Example 1.  A company that manufactures light bulbs claims that a particular type of light bulb will last 850 hours on average with standard deviation of 50.  A consumer…
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Introduction Power analysis is the name given to the process for determining the sample size for a research study.  The technical definition of power is the probability of detecting a…
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Introduction Power analysis is the name given to the process for determining the sample size for a research study.  The technical definition of power is the probability of detecting a…
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