Author Archives: pmean

PMean: Cases and cohorts and controls, oh my!

Some asked a question about a retrospective study where you have a control cohort matched to a case cohort so the cohorts are similar on important (potentially confounding) variables. I pointed out that the two consecutive words “case cohort” are ambiguous and tried to explain  how I define a retrospective cohort design versus a (retrospective) case-control design. Continue reading

PMean: How to run your first Bayesian analysis using jags software in R

Someone wanted to know how to run a Bayesian data analysis for a two group longitudinal study. There are several ways you can do this, but I had to confess I did not have an immediate answer. So I took some time to figure out how to do this using jags software inside of R. I’ve done a fair amount of stuff in jags, but not anything close to a longitudinal design. The general principle is to start with something easy and work your way slowly up to the final analysis. Continue reading

Recommended: Statistical Issues Seen in Non-Statistics Proposals

If you are writing a research grant, there are a lot of statistical issues that you need to consider. This guide, prepared by the American Statistical Association, highlights three areas: framing the problem, designing the study, and specifying the data analysis plan. It doesn’t talk enough about data management, but otherwise it is an excellent resource. Continue reading