P-value is a way to express the likelihood that H0 is not true.
The largest significance level at which we would accept the null hypothesis. It enables us to test the hypothesis without first specifying a value for α. OR
The probability of observing a sample value as extreme as, or more extreme than, the value observed, given that the null hypothesis is true.
If the P-value is smaller then the significance level H0 is rejected. If it is larger than the significance level H0 is not rejected.
If the P-value is less than
- 0.10, we have some evidence that H0 is not true
- 0.05, strong evidence that H0 is not true
- 0.01, Very strong evidence that H0 is not true
- 0.001, extremely strong evidence that H0 is not true