This module provides a variety of information and tools from the American Psychological Association (APA) that will help inspire you as you complete your coursework and plan your career goals. Get discounted access to Academic Writer, APA’s online tool for writing effectively, as well as valuable advice that will help you develop and strengthen your skillset for learning success and future employment. Additionally, explore resources on various psychological issues. This module also includes APA resources on scholarly research and writing; a list of sites providing valuable resources on diversity, equity, and inclusion in psychology education and in the professional community; resources on a career in psychology; and links to career opportunities at the APA. You can also view videos that offer tips on dealing with stress.

We have learned that one-sample t-tests can be used to help us compare a sample mean to a population mean where the population mean is known, but the population standard deviation is unknown. For example, if we wanted to compare the mean number of sleep hours among college students on one campus to the mean number of sleep hours among U.S. college students, what process would we follow to conduct a null hypothesis significance test using a one-sample t-test? This module explains that process.

The paired-samples t-test is used when we take two measurements from each observation in a sample and want to compare the mean of the first measurement to the mean of the second measurement. For example, if we wanted to compare the number of goals a soccer team scored in the first half during a season to the number they scored in the second half, for each observation (game) we would record two measurements, goals scored in the first half and goals scored in the second half, allowing us to compare the mean first half score against the mean second half score.

The independent-samples t-test is used when we take measurements from each observation in two separate groups and want to compare the mean of the first group to the mean of the second group. For example, if we wanted to compare the average level of happiness for a control group and a group that experienced a gratitude-exercise intervention, we would use an independent-samples t-test.