L4, Stats Primer

Question 1

Objectives:
- To understand basic statistical use in biomechanics
- To be able to run a t-test in Excel
- To understand how to interpret p-values

Question 2

Why use stats?

Answer 2

Groups will never be exactly the same, stats help you decide whether the difference is because of an effect or just random variation

Question 3

What is the difference between two-tailed and one-tailed tests?

Answer 3

If change is likely in one direction (+ or -), choose one-tailed test (smaller differences are significant). If not, choose two-tailed.

Question 4

What are 3 reasons why p-values should be interpreted with caution?

Answer 4

1. Don’t aim for significance, aim for understanding
2. p-values can be hacked, leading to higher false positive rates
3. p>0.05 doesn’t always mean no effect