Power analyses and sample size calculations are important parts of many research projects. Often, before data are even collected, it is necessary to calculate and justify the required sample size for ...

Power analyses and sample size calculations are important parts of many research projects. Often, before data are even collected, it is necessary to calculate and justify the required sample size for ...

Jason Fernando is a professional investor and writer who enjoys tackling and communicating complex business and financial problems. Erika Rasure is globally-recognized as a leading consumer economics ...

Let me show you a catchy new graphic and then I’ll explain what’s going on. You’ll see that, in addition to listing the date of the poll, we also list the sample size. And not only do we list the ...

RBR’s lead story today (6/30) has Arbitron defending its sample size. That’s a story we’ve heard for years. For most of my career, Arbitron defended ratings produced by the diary method. They used ...

We present a simple sample-size formula for weighted log-rank statistics applied to clustered survival data with variable cluster sizes and arbitrary treatment assignments within clusters. This ...