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dogs and wolves postscript: Truth Stronger Than Fiction?

(travelling home on the tram after writing previous post, in the amazing State Library of Victoria.

thinking about dogs and wolves, from the French, Entre Chien et Loup, the hour between dog and wolf.  Dusk or twilight, or metaphorically the time between the familiar and the much less familiar….

out of the corner of my eye I noticed a young couple playing with a puppy, in one of their coat pockets.

but on closer inspection, that was no puppy, dog, or even a little wolf.

It was a *ferret*.   (little weasel, polecat creature, not the sort of thing you’d want in a pocket, or on a crowded conveyance)

now what’s the probability of That?

Simple Stats: Food, Friends, Families and F values

Way back when I was a young data analyst, there were limitations to the techniques available for analysing certain types of data. If the data involved counts, for example, there were certain types of transformation, and for repeated measurements over time, one needed ‘fiddle factors’ such as the G-G and H-F, or ‘scattergun’ mighty MANOVA approaches, that lacked in statistical power what they made up in firepower.

These days, even dear old SPSS has some sophisticated regression models, but whereas once there was a ‘trees not forest’ approach of a whole lot of basic tests, looking for ‘significant’ p values, rather than practical effect sizes and generality, now there’s complex ‘forest’ tests, without understanding the output, or even the question.

When talking about simplicity, analysts often recall the monk William of Occam and his “razor” (‘vain to do with more what can be done with fewer’) or misquote Albert Einstein, who probably never actually said ‘everything should be made as simple as possible, but not simpler’).

I like the ancient Greek, Epicurus of Athens, who was big on simple things like food, and friends and families, (although his name has come to be associated with a sort of false. hoggish hedonism, which defeats the purpose). I reckon we need to get a wooden table, some nice fresh food, jugs of (unfermented & fermented) grape, and after the important things like art and sport and the latest clips on Rage night music discussed, then talk about research questions, how they are to be answered, in what sensible but creative manner, so as to get back to other things.

We’d begin with graphical techniques, with the purpose of saying ‘aha’ or ‘Eureka’;  not ‘gosh’ or ‘wow’ or ‘huh?’. Building up with fundamental methods, then perhaps more complex methods if needed, we’d test our models on fresh samples, and looking at that, and effect sizes, as well as confidence intervals and p values. I reckon that’s the sort of data party that even old Epicurus might have attended! http://textpublishing.com.au/books-and-authors/book/travels-with-epicurus/

http://www.dkstatisticalconsulting.com/practical-statistics/  <great book for analysing counts etc using SPSS & Stata>