Meet Betty and Bart Bickerson, husband-and-wife quality analysts who work at different companies. Betty and Bart argue about everything. They argue whether grey is a color. They argue whether tomato is a fruit. They argue whether the chicken came before the egg, and whether the egg tastes better fried, scrambled, or poached. But their relationship didn’t get really rocky until they started to argue about what alpha level, also called the “significance level,” to use for a hypothesis test.

Note: The alpha level is the criterion against which you compare the p-value to determine whether a difference is statistically significant. The alpha level option for the two-sample t test in the Minitab Assistant is shown below:

Listen in as Betty and Bart squabble over what alpha level to use when comparing the mean before and after a process change.

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