Lecture 14: March 7, 2017 Psychology 1010 Exam 2: This Thursday, March 9 during class on chapters 18 and everything in including today. *You do not need to know the BINOMIAL (Chapter 6). *Format. Same as last exam. You need to know the formula for z (both forms), standard error, Cohens d (and criteria for deciding small, medium, large) and Confidence intervals. *What you need to bring for the exam: STUDENT ID!! Calculator, pen, pencil eraser will provide a freshly Xeroxed copy of the Unit Normal (Z) table for each of you (no need to bring that). Last moments of Chapters 18. I may also start Chapter 9 (one sample t) to avoid wasting time. (That way we can get through in comfort rather than racing at the end of the term). You will not need to know one sample t (Chapter 9) for EXAM 2. REVIEW Z tests: The general form of the problem IV Treatment *No treatment: Normal population >> for this group (your population) you are given m which is short for m normal *Treatment: Your sample with sample size n, experiences something special (out of the normal). For that group, you are given (or calculate) M, a sample mean, short for Mspecial DV What it is that is being measured by m and M (e.g. test sore, height, weight, whatever.) REVIEW VI. Things that makes it easy to get a statistically significant effect. z = Mm sM A. In the data 1. Large differences between the means Mm 2. Small SD (variability) in the scores (s) REVIEW B. Things the experimenter has control over 1. The number in the sample (n)>>The larger the n, the easier it is to get a significant effect *That is because sM= ssqrt (n)>>> Larger ns lead to larger Zs!