Statistical power refers to the ability of a statistical test to detect an effect or relationship when it truly exists. It is the probability of correctly rejecting a false null hypothesis.
Type I Error: Type I error occurs when we reject the null hypothesis (assume an effect exists) when it is actually true.
Type II Error: Type II error happens when we fail to reject the null hypothesis (assume no effect) when there is actually an effect present.
Effect Size: Effect size measures the magnitude or strength of a relationship between variables and helps determine practical significance beyond statistical significance.