Author Archives: pmean

PMean: Course proposal on setting up an independent consulting practice

I was asked to prepare a proposal on a short course about consulting for an upcoming Statistics conference. I had talked about this in an earlier blog post. Here is the official submission which includes the course description, outline and objectives, some information about my qualifications to teach the class, and a summary of how this class fits into the theme of the conference. Here’s what I wrote. Continue reading →

PMean: Using BUGS within the R programming environment

I am giving a talk today for the Kansas City R Users group about BUGS (Bayes Using Gibbs Sampler). I have already written extensively about BUGS and the interface to BUGS from within the R programming environment, and you can find these on my category page for Bayesian statistics. Here is a quick overview of why you might want to use BUGS and how you would use it. I’ve included links to the relevant pages on my website so you can explore this topic further on your own. Continue reading →

Pmean: The IRB questions my sample size calculation

I got a question today from someone submitting a research protocol to the Institutional Review Board (IRB). The IRB had some concerns about the power calculation. In particular, they said “The IRB would like to know, how you set the parameters for the power calculation, such as effect size, alpha level. For effect size, you need to have some data to justify or should choose a conservative one.”

Part of this was due to an error in the submission of the protocol. We had specified a paired t-test rather than an independent samples t-test, which is a major gaffe on my part. But they were pushing into some tricky territory and I wanted to clear things up. Here is the response that I suggested that we share with the IRB. Continue reading →