I am working on a research and I need to determine what sample size to use for the study.
Hi,
To calculate the sample size using GPower, the effect size, alpha, desired power (usually 0.80), and type of statistical test must be determined.
Hope this helps.
IYH Dear James Ogundipe to elaborate on Hsin-Yan Chen's answer here is a step-by-step guide on how to calculate the sample size using G*Power:
1. Download and install G*Power from the official website: https://www.psychologie.hhu.de/arbeitsgruppen/allgemeine-psychologie-und-arbeitspsychologie/gpower
2. Launch G*Power and select the appropriate test type from the list of statistical tests. For a simple calculation, let's choose "t-tests" and then "A priori: Compute required sample size - given α, power, and effect size."
3. Fill in the required parameters:
- Effect size: Enter the expected effect size (e.g., Cohen's d).
- α (alpha): Enter the significance level (e.g., 0.05 for a 95% confidence level).
- Power (1 - β): Enter the desired statistical power (e.g., 0.8 for 80% power).
- (this is specific to the t-test) Allocation ratio N2/N1: Enter the ratio of the second group size to the first group size (e.g., 1 for equal group sizes).
4. Click on the "Calculate" button to compute the required sample size.
5. The output will display the required sample size for each group.
Kindly keep in mind that the sample size calculation is based on assumptions, and the actual sample size may vary depending on the specifics of your study.
- Badges
- Science topic
- Similar topics
- Geoscience
- Atmospheric Sciences
- Atmosphere