Practical v. Statistical Significance

The total length of the videos in this section is approximately 8 minutes.

Practical v. statistical significance

Question 1: For a particular study, we expect that larger sample size will lead to

• bigger t-statistic and smaller p-value

• smaller t-statistic and larger p-value

Question 2: The sample size determines:

• practical significance

• statistical significance

Question 3: Check all of the statements that are true.

• Irrelevant but non-zero population differences will be statistically significant, in large enough samples

• Important population differences may not be statistically significant, but only because the sample is too small

• p-value cut-offs for rejecting null hypothesis are arbitrary

• p-value is the probability that the null hypothesis is true

That's all.

During this tutorial you learned:

• The definition of p-value

• The difference between practical significance vs statistical significance

• The relationship between a t-statistic and sample size

• The cutoff threshold of p-values is arbitrary

Terms and concepts:

P-value, practical significance, statistical significance