Kappa is a useful measure of agreement between two raters. Say you have two radiologists looking at X-rays, rating them as normal or abnormal and you want to get a quantitative measure of how well they agree. Kappa is your go-to coefficient. How do you compute it? Well, personally, I use SAS because this is…
Our Project Manager, Jessica, made the very insightful comment at lunch the other day, No one cares how hard it was for you to make. When people are looking to buy your product, all they want to know is what it will do for them. That young woman has a bright future in marketing. Unfortunately…
I think descriptive statistics are under-rated. One reason I like Leon Gordis’ Epidemiology book is that he agrees with me. He says that sometimes statistics pass the “inter-ocular test”. That is, they hit you right between the eyes. I’m a big fan of eye-balling statistics and SAS/GRAPH is good for that. Let’s take this example….
Frequently, I hear adults who should know better argue against learning something, whether it is algebra, analysis of variance or learning a programming language. They say, I’m 47 years old and I’ve never used (insert thing I didn’t learn here). Yes, that is true. However, if you had learned it, there is a good chance…
I read a lot. This year, I finished 308 books on my Kindle app, another dozen on iBooks, a half-dozen on ebrary and 15 or 20 around the house. I don’t read books on paper very often any more. It’s not too practical for me. I go through them at the rate of about a book…
What if you wanted to turn your PROC MIXED into a repeated measures ANOVA using PROC GLM. Why would you want to do this? Well, I don’t know why you would want to do it but I wanted to do it because I wanted to demonstrate for my class that both give you the same…
Any time you learn anything new it can be intimidating. That is true of programming as well as anything else. It may be even more true of using statistical software because you combine the uneasiness many people have about learning statistics with learning a new language. To a statistician, this error message makes perfect sense:…
In August, I attended a class at Unite 2014 (on Unity game development) and the presenter said, “And some of you, your code won’t run and you’ll swear you did exactly what was shown in the examples. But, of course, all of the rest of us will know that is not true.” This perfectly describes…
Computing confidence intervals is one of the areas where beginning statistics students have the most trouble. It is not as difficult if you break it down into steps, and if you use SAS or other statistical software. Here are the steps: 1. Compute the statistic of interest– that is mean, proportion, difference between means 2….
SAS Enterprise Miner – Free, on a Mac – Bet You Didn’t See That Coming … but how the hell do you get your data on it? I wanted to test SAS Text Miner and was surprised to find the university did not have a license. No problem – and it really was, astoundingly, no…