PSY 207 Lecture Notes - Lecture 8: Null Hypothesis, Statistical Hypothesis Testing, Sampling Error
Document Summary
Steps to hypothesis testing: we want to know if some group of scores is different from another group of scores. But because of variability in populations and sampling error: we need to guard against the possibility that differences between groups are merely due to chance. To guard against differences that aren"t really genuine. It"s possible that the difference we suspect does not exist. It"s possible that the manipulation that we introduced had no effect. So we hope to find a difference that is unlikely to be the result of chance. In which case, we have confidence that the difference is genuine. Step 1: state the hypothesis: what we want to know: does treatment x affect behavior y ? . But: even if we know original , we definitely don"t know new . Hypothesis testing in statistics is testing whether null hypothesis is wrong . Note: that this is not the same thing as a research hypothesis, which is a prediction.
