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Statistics Resources

This guide contains all of the ASC's statistics resources. If you do not see a topic, suggest it through the suggestion box on the Statistics home page.

G*Power for T-tests Tutorial

T-tests

Single Sample T-test

The single sample t-test is used to compare the sample mean from one sample to a given population mean. The purpose of this test is to determine if the sample is drawn from (or different from) the given population.

Basic Hypotheses

Null: The sample mean is not significantly different from the population mean.
Alternative: The sample mean is significantly different from the population mean.

Real-World Examples
  • Determining if a treatment is effective at reducing symptoms or improving scores based on population parameters (not control group comparison)
    • Does CBT increase the proportion of patients that successfully complete therapy?
    • Does the Read with Me program improve reading scores?
    • Is the new facility able to produce more products than previous ones?
  • Determining if there's been a change in some dynamic (i.e. IQ) since the time that the parameter was generated
    • Has the average IQ increased since 2000?
    • Does the current class perform better on exams than previous students?

See the T-Tests page for more information on this topic.