Paired t-Test

SPC XL 2010 now supports a Paired t-Test. A Paired t-Test is used when data for each sample are related or paired in a particular way. To use a Paired t-Test, the following criteria should be met.

1. The number of data points in each dataset should be identical and organized in pairs.
2. Each pair should be related in some way. The most common method is before and after. In pharmaceuticals, you might observe a patient's blood pressure before and after administering a drug. In product design, you might observe the torque to turn a bearing before and after a coating is applied. The "pairing" is what makes a Paired t-Test differ from a non-paired t-Test (called t-Test).

Example

Source Data

Data for the torque to turn a bearing before and after coating. The same bearing was used for both before and after.

Select "SPC XL" - "Analysis Tools" - "Paired t Test Matrix". Do not select column A; you should only select the range of numeric data.

Results