What is effect size in statistics?

What is effect size in statistics?

Effect size is a quantitative measure of the magnitude of a phenomenon. It helps to understand the strength of a relationship or the size of a difference.

Why is effect size important?

Effect size is important because it provides context to statistical results, helping researchers understand the practical significance of their findings.

Can you give me an example of effect size?

Sure! For instance, in a study comparing two teaching methods, if the average test score for method A is 80 and for method B is 70, the effect size can indicate how significant that difference is.

How do I calculate effect size?

Effect size can be calculated using various formulas, such as Cohen's d for comparing two means, which is the difference between the means divided by the pooled standard deviation.