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 ...

Define statistical power List the potential consequences of doing a study that has low power, and also a study that has too much power. Explain what a type 1 and type ...

Over-dispersed count data are frequently observed in clinical trials where the primary endpoint is occurrence of clinical events. Sample sizes of comparative clinical trials with these data are ...

Investigator: Right, here is the data set. What is the P value? Statistician: Oh, hello again. Look, I have some concerns about how the endpoint was assessed... Investigator: Fine, I'll add a sentence ...

For a desired power of detecting the association between a disease and several potential risk factors in case-control studies, Yang (1978, Biometrika 65, 635-640) and Halperin (1980, Biometrika 67, ...

Investopedia contributors come from a range of backgrounds, and over 25 years there have been thousands of expert writers and editors who have contributed. Somer G. Anderson is CPA, doctor of ...