Examples Example 1. A clinical dietician wants to compare two different diets, A and B, for diabetic patients.  She hypothesizes that diet A (Group 1) will be better than diet…
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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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Examples Example 1. A company markets an eight week long weight loss program and claims that at the end of the program on average a participant will have lost 5…
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There are a number of situations that can arise when the analysis includes between groups effects as well as within subject effects. We start by showing 4 example analyses using…
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Chapter Outline 4.1 Robust Regression Methods         4.1.1 Regression with Robust Standard Errors         4.1.2 Using the Cluster Option         4.1.3 Robust Regression         4.1.4 Quantile Regression…
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Classes and Seminars Learning Modules Frequently Asked Questions Important Links Where to run SAS? How to get SAS? Installing, Customizing, Updating, Renewing SAS SAS Online Documentation Statistical Analyses Data Analysis…
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How do you combine SAS format libraries?  Say you have a format library in e:tempdata1 and a format library in e:tempdata2 and you want to combine them.  Here is how…
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The following code creates a table of results for a series of logistic regressions. The resulting table will look like the one shown below. The coefficients for each variable is…
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SAS does not have any built-in options for formatting an axis label on separate lines. For example, in the graph below you may feel that the x-axis label “writing score…
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This page shows how to run logistic, random intercept, and random slope regression models using proc nlmixed. This is done to demonstrate the use and flexibility of proc nlmixed, and…
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