Occasionally when running a logistic/probit  regression we run into the problem of so-called complete separation or quasi-complete separation. On this page, we will discuss what complete or quasi-complete separation is…
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Purpose: This page introduces the concepts of the a) likelihood ratio test, b) Wald test, and c) score test. To see how the likelihood ratio test and Wald test are…
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When I run my OLS regression model with a constant I get an R2 of about 0.35 and an F-ratio around 100. When I run the same model without a…
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FAQ: What is regression through the origin? Regression through the origin is a technique used in some disciplines when theory suggests that the regression line must run through the origin,…
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Occasionally when running a logistic regression we would run into the problem of so-called complete separation or quasi-complete separation. On this page, we will discuss what complete or quasi-complete separation…
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Consider the three-way ANOVA, shown below, with a significant three-way interaction. There are 24 observations in this analysis. In this model a has two levels, b two levels and c…
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This page shows the survey setups for common public use data sets in various statistical packages, including SUDAAN 10.1, Stata 12.1 and SAS 9.3.  If you are using an earlier…
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A common problem is transferring data from one statistical package to another.  If you are converting a SAS to SPSS using SPSS version 11 and above, then see this FAQ…
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A common problem is transferring data from one statistical package to another.  Converting data from SPSS to SAS is not very difficult, as the example below illustrates.  We start by…
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!!!!! This page is under construction !!!!! Examples of Latent Class Analysis Example 1. At a university you wish to measure satisfaction with the university library among graduate students and…
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