2. Introduction to Statistics for the Social Sciences SBS200, COMM200, GEOG200, PA200, POL200, or SOC200 Lecture Section 001, Fall, 2014 Room 120 Integrated Learning Center (ILC) 10:00 - 10:50 Mondays, Wednesdays & Fridays. http://www.youtube.com/watch?v=oSQJP40PcGI

3. Labs continue this week

4. Schedule of readings Before next exam (September 26 th ) Please read chapters 1 - 4 in Ha & Ha textbook Please read Appendix D, E & F online On syllabus this is referred to as online readings 1, 2 & 3 Please read Chapters 1, 5, 6 and 13 in Plous Chapter 1: Selective Perception Chapter 5: Plasticity Chapter 6: Effects of Question Wording and Framing Chapter 13: Anchoring and Adjustment

5. Reminder A note on doodling Hand in homework assignment

6. No Homework Just study for exam

7. By the end of lecture today 9/24/14 Use this as your study guide Standard deviation Variance Memorizing the four definitional formulae z scores – counting by standard deviations’s

8. Exam 1 – This Friday – September 26 th Study Guide is online Bring 2 calculators (remember only simple calculators, we can’t use calculators with programming functions) Bring 2 pencils (with good erasers) Bring ID

9. Warm-up Review of pop quiz results 1. What is a “deviation score” 2. Preston has a deviation score of 2: What does that tell us about Preston? Is he taller or shorter than the mean? And by how much? Are most people in the group taller or shorter than Preston 3.Mike has a deviation score of -4: What does that tell us about Mike? Is he taller or shorter than the mean? And by how much? Are most people in the group taller or shorter than Mike 4.Diallo has a deviation score of 0: What does that tell us about Diallo? Is he taller or shorter than the mean? And by how much? Are most people in the group taller or shorter than Diallo? 5.Please write the formula for the standard deviation of a population 6.Please draw 3 curves showing 1, 2 & 3 standard deviations from mean Mean Diallo is 0” Mike is -4” Hunter is -2 Shea is 4 David 0” Preston is 2” Deviation scores Mike Shea Preston Diallo How far away is each score from the mean?

10. Standard deviation: The average amount by which observations deviate on either side of their mean Based on difference from the mean Mean Diallo is 0” Mike is -4” Hunter is -2 Shea is 4 David 0” Preston is 2” Deviation scores Mike Shea Preston Diallo Generally, (on average) how far away is each score from the mean? Remember, it’s relative to the mean Please memorize these “Sum of Squares” “n-1” is “Degrees of Freedom” “n-1” is “Degrees of Freedom” Remember, We are thinking in terms of “deviations”

11. Raw scores, z scores & probabilities Please note spatially where 1 standard deviation falls on the curve

12. Raw scores, z scores & probabilities 68% 95%99.7% Please note spatially where 1 standard deviation falls on the curve

13. These would be helpful to know by heart – please memorize areas 1 sd above and below mean 68% 2 sd above and below mean 95% 3 sd above and below mean 99.7%

14. Raw scores, z scores & probabilities Mean = 50 S = 10 (Note S = standard deviation) If we go up one standard deviation z score = +1.0 and raw score = 60 If we go down one standard deviation z score = -1.0 and raw score = 40 1 sd above and below mean 68% z = -1 z = +1

15. Mean = 50 S = 10 (Note S = standard deviation) If we go up two standard deviations z score = +2.0 and raw score = 70 If we go down two standard deviations z score = -2.0 and raw score = 30 2 sd above and below mean 95% Raw scores, z scores & probabilities z = -2 z = +2

16. Mean = 50 S = 10 (Note S = standard deviation) If we go up three standard deviations z score = +3.0 and raw score = 80 If we go down three standard deviations z score = -3.0 and raw score = 20 3 sd above and below mean 99.7% Raw scores, z scores & probabilities z = -3 z = +3

17. If score is within 2 standard deviations (z < 2) “not unusual score” If score is beyond 2 standard deviations (z = 2 or up to 3) “is unusual score” If score is beyond 3 standard deviations (z = 3 or up to 4) “is an outlier” If score is beyond 4 standard deviations (z = 4 or beyond) “is an extreme outlier”

18. Movie Packages We sampled 100 movie theaters (Two tickets, large popcorn and 2 drinks) Mean = $37 Range = $27 - $47 2728 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 Price per Movie Package 12 10 8 6 4 2 0 Frequency What’s the ‘typical’ or standard deviation? Standard Deviation = 3.5

19. Amount of Bonuses (based on commission) We sampled 100 retail workers Mean = $50 Range = $25 - $75 What’s the largest possible deviation? What’s the ‘typical’ or standard deviation? Standard Deviation = 10 $75 – $50= $25 $25 – $50= -$25 68% 95% 99.7%

20. Exam 1 Review