Welch's T-Test Calculator

Understanding Welch's T-Test

Welch's t-test is a statistical test used to determine if there is a significant difference between the means of two independent groups. It is particularly useful when the variances of the two groups are not assumed to be equal, or when sample sizes are different. Unlike the Student's t-test, Welch's t-test adjusts the degrees of freedom to account for unequal variances, making it more robust in real-world scenarios.

This test is commonly applied in various fields such as biology, psychology, and economics to compare experimental groups. For example, it can be used to compare the effectiveness of two different teaching methods by analyzing test scores from two groups of students, or to compare the average income of two different demographic groups.

The key outputs of Welch's t-test include the t-statistic, which measures the difference between the sample means relative to the variability within the samples; the p-value, which indicates the probability of observing the results if there is no actual difference between the means; degrees of freedom, adjusted for unequal variances; and the confidence interval, providing a range within which the true difference in means is likely to lie.