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  Topic: mafs question< Next Oldest | Next Newest >  

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Joined: Oct. 2006

(Permalink) Posted: Mar. 11 2011,07:23   

Quote (George @ Mar. 11 2011,07:15)
Another thought: counts data are often Poisson distributed and not suitable for t-tests / ANOVA.  However, a simple transformation should work the trick.  IIRC, a square root transformation is often best for counts data.

Or a log-transformation. Or run a glm with a log-link and family=poisson option [R code: glm(counts~1,family=poisson,data=teh.sample] and test whether the intercept is significantly different from what's expected: |intercept - exp(mu_0)|/se(intercept)~N(0,1).

After much reflection I finally realized that the best way to describe the cause of the universe is: the great I AM.


  26 replies since Mar. 10 2011,11:59 < Next Oldest | Next Newest >  


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