Paired Samples T-Test Calculator

Understanding Paired Samples T-Test

The Paired Samples T-Test is a statistical test used to determine if there is a statistically significant difference between the means of two related groups. "Related" means each subject in one group is paired with a subject in the other group (e.g., measurements before and after an intervention on the same individuals, or comparing measurements from twins).

This test is appropriate when you want to know if the average difference between pairs of observations is significantly different from zero. For example, you might use a paired t-test to see if a weight loss program is effective by measuring participants' weight before and after the program.

• T-Statistic: Measures the size of the difference relative to the variation in your sample data.
• P-Value: Indicates the probability of observing a t-statistic as extreme as, or more extreme than, the one calculated if there is no real difference between the means. A small p-value (typically ≤ 0.05) suggests that the difference is statistically significant.
• Degrees of Freedom: Related to the sample size, it affects the shape of the t-distribution. For paired t-test, it's typically n-1, where n is the number of pairs.
• Confidence Interval: Provides a range of values within which the true mean difference likely lies.

Learn more about Paired Samples T-Test on resources like Wikipedia or statistics textbooks.