PSYCH 127A Midterm: Psych 100A Notes
Document Summary
Standard deviation (sigma sub x) is known--- z distribution. Point estimates (using the sample stat to make a guess of what"s happening in the population) Confidence intervals (range of values around a sample statistic that have a certain probability of containing the population parameter) Conduct null hypothesis test (z-test, t-test): is one group statistically different than another group? 90% of what psychologists due, but becoming less used: are results due to chance sampling or do they reflect a real difference. Estimate the size of an experimental effect: what is the magnitude of an experimental effect? (ex) how big is the difference between the affect of advil and tylenol. Use sample results to directly estimate population values: what is the size of the difference, point estimation (using sample statistic as a guess for population value) Based on poll results we estimate that candidate a will obtain 60% of the vote: interval estimation -> confidence interval.
