# Effect size for GEMMA is a MUST

To: @Zach, @Pjotr
From: robwwilliams
Regarding: Getting a readout of effect size and polarity of effect from GEMMA
Request Type: New feature for GEMMA, User requires these data

Main Message: Let's Just Do It. Can be done as a kludge. Just plot the beta of the regression equation of the SNP status (ususally two or three states codes as 0, 1, 2 or -1,0, +1) against the phenotype.
The slope is roughly the effect size. This is good enough for most users. The only got-you is slight inflation of due to kinship structure and the Beavis effect when the sample size is low.
QUESTION—can I upload an image from Amelie Baud's talk on effect size?

=> /pictures/effect-size-for-gemma.png