Decision Rule Calculator

In hypothesis testing, we want to know whether we should reject or fail to reject some statistical hypothesis.

To make this decision, we compare the p-value of the test statistic to a significance level we have chosen to use for the test. If the p-value is less than the significance level, we reject the null hypothesis. Otherwise, we fail to reject the null hypothesis.

This calculator tells you whether you should reject or fail to reject a null hypothesis based on the value of the test statistic, the format of the test (one-tailed or two-tailed), and the significance level you have chosen to use.

One-tailed or two-tailed hypothesis?

One-tailed

Two-tailed

Significance level

0.01

0.05

0.10

Z-statistic or t-statistic?

Z-statistic

t-statistic

Degrees of freedom

Value of the test statistic

Decision Rule: fail to reject the null hypothesis

Explanation:

The p-value for a Z-statistic of 1.34 for a two-tailed test is 0.18025. Since this p-value is greater than 0.05, we fail to reject the null hypothesis.