Using and Interpreting Cronbach’s Alpha

I. What is Cronbach’s alpha? Cronbach’s alpha is a measure used to assess the reliability, or internal consistency, of a set of scale or test items. In other words, the reliability of any given measurement refers to the extent to which it is a consistent measure of a concept, and Cronbach’s alpha is one way […]

Reshaping Data from Wide to Long

When performing data analysis, we often need to “reshape” our data from wide format to long format. A common example of wide data is a data structure with one record per subject and multiple columns for repeated measures. For example: id gender race trt day1 day2 day3 1 F 0 0 19.81310 18.05777 14.84996 2 […]