How to specify the level of significance？

To specify the level of significance, you need to choose a value for alpha (α), which is typically set to 0.05 or 0.01. This value represents the probability of rejecting the null hypothesis when it is actually true.

For example, if you choose a level of significance of 0.05, you are saying that you are willing to accept a 5% chance of rejecting the null hypothesis when it is actually true. This means that you are willing to accept a 5% chance of making a type I error (rejecting a true null hypothesis).

The level of significance should be chosen based on the specific research question and the consequences of making a type I error. If the consequences of making a type I error are severe, a lower level of significance may be appropriate.