Introduction to Statistics in Psychology PSY 201 Greg Francis PhD Department of Psychological Sciences Psychological Sciences Building Room 3174 765 494 6934 email gfrancis purdue edu http www psych purdue edu gfrancis Classes PSY201 index html Study Guide for Exam 3 Exam Date November 22 2010 during the regular class period The exam will consist of 10 15 short answer questions that will be similar to the problems on the homework but usually smaller However some of the questions will be essay questions where you must describe a concept You will be expected to perform some calculations so bring a calculator If any tables will be necessary I will provide them I will not provide an equation sheet with the exam Instead you should create a crib sheet consisting of one piece of paper both sides can be used My advice is to at least write out step by step what you do to carry out a hypothesis test and to create a confidence interval for every statistic we have discussed The crib sheet must be hand written no photocopies I will be happy to look over your crib sheet before the exam to check for any mistakes Know all of the following information Generally you need to both know how to do various calculations and understand the concepts behind the calculations The former you can verify by doing practice problems The latter you can verify by creating a written description of what the calculations are doing If the written description makes sense then you probably understand the concept In general you need to be able to do the calculations discussed in lecture and on the homework assignments For conceptual issues you need to understand the concepts discussed in lecture and the readings will often provide material that will help you do that Lecture 23 1 Understand the need for the Fisher z transform when testing correlations 2 Know the sampling distribution of Fisher z transform scores and the formula for standard error of zr 3 Know how to run hypothesis tests for correlations using the Fisher z transform 4 Know how to run a hypothesis test for the special case with H0 0 Lecture 24 1 Know how to build a confidence interval using Fisher z transform scores 1 2 Know how to run hypothesis tests for proportions Know the sampling distribution and the formula for standard error 3 Know how to build a confidence interval for a proportion use the formula for standard error based on little p and q Lecture 25 1 Understand the distinction between a one sample test and a two sample test 2 Be able to run a two sample hypothesis test for means when homogeneity of variance is assumed Know the sampling distribution and the calculation of standard error In particular know how to pool the sample variances from the two samples using any of the formulas Know the degrees of freedom Lecture 26 1 Be able to test for homogeneity of variance Know the sampling distribution the test statistic F ratio and how to get each of these terms Know what the conclusion of the test means about running a hypothesis test for means 2 Be able to run a two sample hypothesis test for means when homogeneity of variance is not assumed Know the formulas for standard error and degrees of freedom Lecture 27 1 Understand the distinction between a two sample case with independent and dependent means Be able to recognize which case applies to a given situation 2 Be able to run a two sample hypothesis test for dependent means Know the test statistic the sampling distribution and the calculation of standard error Lecture 28 1 Be able to carry out a two sample hypothesis test involving correlations 2 Be able to carry out a two sample hypothesis test involving independent samples for proportions 3 Know what margin of error refers to Lecture 29 1 Be able to carry out a two sample hypothesis test involving dependent samples for proportions 2 You need to know how to run every type of hypothesis test that we have discussed 1 One sample correlation with Fisher z transform H0 a and how to create a confidence interval 2 One sample correlation special case H0 0 and how to create a confidence interval 3 One sample proportion H0 P a and how to create a confidence interval 4 Two sample independent means homogeneity of variance H0 1 2 5 Two sample independent means no homogeneity of variance H0 1 2 6 Test for homogeneity of variance H0 12 22 7 Two sample dependent means H0 0 8 Two sample independent correlations H0 1 2 9 Two sample independent proportions H0 P1 P2 10 Two sample dependent proportions H0 P P1 P2 0 3