President Donald Trump - people seem to either love him or hate him. Which makes for an interesting data-analysis topic ... tracking Trump's approval rating. Follow along as I explore some data! I'll start with what I consider the 'best' approval-rating graph I've found so far. Here's a screen-capture of

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A useful feature in PROC SGPLOT is the ability to easily visualize subgroups of data. Most statements in the SGPLOT procedure support a GROUP= option that enables you to overlay plots of subgroups. When you use the GROUP= option, observations are assigned attributes (colors, line patterns, symbols, ...) that indicate

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If you want to bootstrap the parameters in a statistical regression model, you have two primary choices. The first, case resampling, is discussed in a previous article. This article describes the second choice, which is resampling residuals (also called model-based resampling). This article shows how to implement residual resampling in

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The other day I was playing around with the voter registration data for all ~8 million registered voters in North Carolina (yes - this guy knows how to have fun!), and I got to wondering what last names were the most common. I summarized the data by co...
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If you want to bootstrap the parameters in a statistical regression model, you have two primary choices. The first is case resampling, which is also called resampling observations or resampling pairs. In case resampling, you create the bootstrap sample by randomly selecting observations (with replacement) from the original data. The

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This past Sunday was the last day of the NC State Fair, and we broke some records this year! Can you guess what those records were? I'll ramble on about the fair to give you time to come up with your guess, and then I'll let you know about the Th...
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Have you noticed a lot of graphs popping up lately, about politicians, voters, and elections? ... Well of course - it's an election year! If you follow my blog posts, then you're probably a bit "smarter than the average bear" when it comes to scrutiniz...
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A SAS programmer asked how to rearrange elements of a matrix. The rearrangement he wanted was rather complicated: certain blocks of data needed to move relative to other blocks, but the values within each block were to remain unchanged. It turned out that the mathematical operation he needed is called

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Any of you who are even slightly into politics, or have followed any news lately, have probably seen something about the DNA test Elizabeth Warren took to prove/disprove her Native American ancestry. The test indicates she might have had a Native Ameri...
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