So I’m presenting an example today similar to the one that I’m also giving at an elementary school showing students exactly what the heck do biostatisticians do.  And that is using something called a Fisher’s exact test to see if the distribution of categories between two groups are the same or not.  Now, I’m using candy bars for my elementary school presentation but I’m going to use something here that is even more fun and yummy.  An example from my trilogy!!  Oh, come on! You just know that’s more fun and yummy.  Don’t lie!  So say, we have Tina again and we again want to determine the kind of dimension she is in.  And if she’s in a good dimension, she’s probably working at that computer store in that shopping center with the cool Barnes & Nobel where she can order the Order of The Dimension series.  But if she’s in a bad dimension, she’s probably doing something like basking in the sun at a tropical resort.  Now, let’s say that in 5 out of 6 good dimensions, she’s at the shopping center but in the last good dimension, she’s also at an island resort on the weekend.  But in 18 out of 20 bad dimensions, she’s at the resort — which might be nice — if that’s your cup of tea — but in the other 2 dimensions, she’s also at a shopping center, ordering a series of … you know.  So comparing the numbers that she is at the resort on the weekend, we have 1/6 vs. 18/20 and applying the Fisher’s exact test, using the fancy formula given here, we get a p-value 0.03 which is less than 0.05.  Which means the chances of being at the resort versus the shopping center between the good and bad dimensions appear to be significantly different.  But we’ll cover more on significance and the p-value next time.  Till then, don’t you just want to go to that Barnes & Nobel at your local shopping center and order your very own series of Order of The Dimensions or would you really prefer to spend your weekend here?

 

xanadu-tropical-resort

Yeah. Though so! B&N for the win!  Don’t lie!

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