# PSYB01H3 Chapter 13: chapter 13 notes

## Document Summary

Inferential statistics are necessary because the results of a given study are based on data obtained from a single sample of research participants. If researchers ever study entire populations; their findings are based on sample data. Example: people in one state might tell you that 57% prefer the democratic candidate and that. Reflects any true differencein the population means, plus. Inferential statistics give the probability that the difference between means reflects random error than a real difference. Null and research hypothesis: statistical inference begins with a statement of the null hypothesis and a research (or alternative) hypothesis. this is what is meant by statistical significance. Independent variable did have an effect: logic of the null hypothesis. we all use probabilities frequently in everyday life: example: the weather forecaster says there is a 10% chance of rain today; this means that the likelihood of rain is very low.