A researcher is exploring differences between men and women on 'number of different recreational drugs used.' The researcher collects data on a sample of 50 men and 50 women between the ages of 18-25. Each participant is asked 'how many different recreational drugs have you tried in your life?' The IV is gender (male/female) and the DV is 'number of reported drugs. What are the power issues and what influences statistical power?
Statistical power is your chance of finding a statistically significant effect, assuming that there is one. Here, you're looking for a difference in drug use between men and women. Assuming that there is a gender difference, power tells you how likely you are to find that difference in your statistical analyses. Power ranges between 0 and 1 (or 0 and 100%); for example, if power is 0.5, you have a 50% chance of finding a difference that's there. We ideally want power to be high; there's not much point in ...
This solution defines statistical power and explains three main factors affecting power.