2 Sample Test

A test used to measure the statistical difference between the means (a.k.a. average) of two continuous (a.k.a. variable or numerical) values. This test is best for independent variables that are sampled from different groups (e.g., same type of output measurements from two different machines or manufacturing plants, or same performance metrics between two different call centers, or same sales metrics between reps from different stores, etc.). It is generally used when the distribution for the continuous value is normal, hence the use of the mean. When the distribution is non-normal, the mean may not be valid so the median would be a better measure for central tendency; in those cases, try the Mann-Whitney Test. For data having dependent variables, use a Paired T Test.
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