She wants to be an airborne ranger

I wanna be an airborne ranger, Live the life of guts and danger.* If you are an 80's movie buff, you might remember the scene in The Breakfast Club where Bender, the juvenile delinquent played by Judd Nelson, distracts the principal by running through the school singing this song. Recently, [...]
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Correlations between groups of variables

Typically a correlation analysis reports the correlations between all pairs of variables, including the variables with themselves. The resulting correlation matrix is square, symmetric, and has 1s on the main diagonal. But suppose you are interested in only specific combinations of variables. Perhaps you want the pairwise correlations between one [...]
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Regression coefficient plots in SAS

Last week's post about odds ratio plots in SAS made me think about a similar plot that visualizes the parameter estimates for a regression analysis. The so-called regression coefficient plot is a scatter plot of the estimates for each effect in the model, with lines that indicate the width of [...]
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Odds ratio plots with a logarithmic scale in SAS

I recently read an argument by Andrew Wheeler for using a logarithmic axis for plotting odds ratios. I found his argument convincing. Accordingly, this blog post shows how to create an odds ratio plot in SAS where the ratio axis is displayed on a log scale. Thanks to Bob Derr [...]
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Wealth and winning in NC high school athletics

The Raleigh News & Observer published a front-page article about the effect of wealth and poverty on high school athletics in North Carolina. In particular, the article concluded that "high schools with a high percentage of poor students rarely win titles in the so-called country club sports—tennis, golf and swimming—and [...]
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The relationship between toothlessness and income

My colleague Robert Allison finds the most interesting data sets to visualize! Yesterday he posted a visualization of toothless seniors in the US. More precisely, he created graphs that show the estimated prevalence of adults (65 years or older) who have had all their natural teeth extracted. The dental profession [...]
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Visualizing the distribution of ACT scores

My son is in high school and plans to take the ACT, a standardized test to assess college aptitude and readiness. My wife asked, "What is a good score for the ACT?" I didn't know, but I did a quick internet search and discovered a tabulation of scores for the [...]
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How to Winsorize data in SAS

Recently a SAS customer asked how to Winsorize data in SAS. Winsorization is best known as a way to construct robust univariate statistics. The Winsorized mean is a robust estimate of location. The Winsorized mean is similar to the trimmed mean, and both are described in the documentation for PROC [...]
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Merge observed outcomes into a list of all outcomes

When you count the outcomes of an experiment, you do not always observe all of the possible outcomes. For example, if you roll a six-sided die 10 times, it might be that the "1" face does not appear in those 10 rolls. Obviously, this situation occurs more frequently with small [...]
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The spiral of splatter

"Daddy, help! Help me! Come quick!" I heard my daughter's screams from the upstairs bathroom and bounded up the stairs two at a time. Was she hurt? Bleeding? Was the toilet overflowing? When I arrived in the doorway, she pointed at the wall and at the floor. The wall was [...]
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