To determine whether to reject the null hypothesis using the t-value, compare the t-value to the critical value. The critical value is t_{α/2, n–p-1}, where α is the significance level, n is the number of observations in your sample, and p is the number of predictors.

If the absolute value of the t-value is greater than the critical value, you reject the null hypothesis. If the absolute value of the t-value is less than the critical value, you fail to reject the null hypothesis. You can calculate the critical value in Minitab or find the critical value from a t-distribution table in most statistics books. For more information calculating the critical value in Minitab, go to Using the inverse cumulative distribution function (ICDF) and click *Use the ICDF to calculate critical values*.