test-retest sample size

Hello, I'm having problems calculating the required sample size for my PhD study. I have designed my first study, which is comparing moral reasoning abilities in people with a brain injury to a healthy comparison group. I have used previous similar research and G Power to estimate the...

Hello, I am developing psychometric questionnaire to assess project manager competencies in the region (which they actualy have - not state they do). I`ve backed up my questions with some previous research - there is about 140 competencies grouped in 8 "blocks" (individuality excluded). I`ve...