Critical value example

Let's say we conduct a hypothesis test to determine if the mean weight of a certain population is significantly different from 150 pounds.

The critical value is a value that determines the cutoff point for accepting or rejecting the null hypothesis. In this example, if we use a significance level of 0.05 (meaning we are willing to accept a 5% chance of making a Type I error), then the critical value for a two-tailed test would be ±1.96.

If our calculated test statistic falls outside of this critical value range, we would reject the null hypothesis and conclude that the mean weight of the population is significantly different from 150 pounds.