Modern Languages Row A Row B Row C Row D Row E Row F Row G Row H Row J Row K Row L Row M table Row C Row D Row E Row F Row G Row H Row J Row K Row L Row M Projection Booth table Row C Row D Row E Row F Row G Row H Row J Row K Row L Row M R/L handed broken desk Stage Lecturer’s desk Screen 1

MGMT 276: Statistical Inference in Management Spring 2015

Schedule of readings Before next exam: February 17 th Please read chapters & Appendix D & E in Lind 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

By the end of lecture today 2/12/15 Measures of variability Standard deviation Variance Review for Exam 1

No Homework due Tuesday, Feb 17 th Just study for Exam 1

Exam 1 – This Tuesday February 17 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 Stats Review by Jonathon When: Monday evening February 16 th - 6:00 – 7:50pm Where: Bio East 100 Cost: $5.00 Stats Review by Jonathon When: Monday evening February 16 th - 6:00 – 7:50pm Where: Bio East 100 Cost: $5.00

Review of Homework Worksheet

– 5 = – 5 = = = = Review of Homework Worksheet

– 6 = – 6 = = = = Review of Homework Worksheet

Must be complete and must be stapled

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”

Summary of 7 facts to memorize

Movie Packages We sampled 100 movie theaters (Two tickets, large popcorn and 2 drinks) Mean = $37 Range = $27 - $ Price per Movie Package Frequency Standard Deviation = 3.5

Amount of Bonuses (based on commission) We sampled 100 retail workers Mean = $50 Range = $25 - $75 Standard Deviation = 10 68% 95% 99.7%

Mean = 1700 pounds Range = 1200 – 2100 What’s the ‘typical’ or standard deviation? Standard Deviation = 200 Pounds of pressure to break casing on an insulator (We applied pressure until the insulator casing broke) What’s the largest possible deviation? 1200 – 1700 = – 1700 = 400

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

Waiting time for service at bank We sampled 100 banks (From time entering line to time reaching teller) Mean = 3 minutes Range = What’s the largest possible deviation? What’s the ‘typical’ or standard deviation? Standard Deviation = – 3.0= – 3.0= -.8

Scores, standard deviations, and probabilities Actually Actually To be exactly 95% we will use z = 1.96

Random sampling vs Random assignment Random sampling of participants into experiment: Each person in the population has an equal chance of being selected to be in the sample Random assignment of participants into groups: Any subject had an equal chance of getting assigned to either condition (related to quasi versus true experiment) Review

From the lab review Mariska works at a cattle ranch, and wants cattle to gain as much weight as possible. Mariska wants to know if the new feed makes a difference in how much weight the cattle gain. She gathers the first 100 cows that she finds in the meadow, and then randomly assigns those 100 cows into two groups (50 each group) One group gets the new feed for 6 months, while the other group of cattle gets the old feed. She is not looking for any trends over time, but is just looking for a difference between the two types of cow chow (feed). Independent Variable? Dependent Variable? IV: Nominal Ordinal Interval or Ratio? DV: Nominal Ordinal Interval or Ratio? IV: Continuous or discrete? DV: Continuous or discrete? Type of Cow Chow Weight IV: Nominal DV: Ratio IV: Discrete DV: Continuous Random Assignment? Random Assignment (True Expt) Random Sampling? No, only convenience sampling Between or within? Between Participant Design Cross Sectional or Time Series Cross Sectional

Question 9 - Does amount of sleep (4 vs 8 hours) affect class attendance? Selected 350 students from 38,000 undergraduates at U of Washington and randomly assigned students into two groups. Group 1 gets 4 hours sleep What is the independent variable? How many levels are there of the IV? Group 2 gets 8 hours sleep -Amount of sleep -2 levels (4 hours vs 8 hours) What is the dependent variable? What is population and sample? -Class attendance -Population: whole school -Sample: group of 350 students What is statistic ? -Average class attendance for 350 students Note: Parameter would be what we are guessing for the whole school based on these 350 students Quasi versus true experiment (random assignment)? -True Random sample? -Doesn’t say in the problem, so we have to assume “no”

Question 10 - Does gender of the teacher affect test scores for the students in California? Selected 150 students from Santa Monica and created two groups. Group 1 gets a female teacher What is the independent variable? How many levels are there of the IV? Group 2 gets a male teacher -Gender of teacher -2 levels (male vs female teacher) What is the dependent variable? What is population and sample? -Test Scores -Population: California -Sample: group of 150 students from Santa Monica What is statistic ? -Average test score for 150 students Quasi versus true experiment (random assignment)? -Doesn’t say in the problem, so we have to assume “no” Random sample? -No – Random sample would require that everyone in California be equally likely to be chosen.

Writing Assignment – Pop Quiz 1. What does this symbol refer to? 2. What does this symbol refer to? 5. What does this symbol refer to? 3. What does this symbol refer to? 4. What does this symbol refer to? What is it called? What does it mean? Is it referring to a sample or population? What is it called? What does it mean? Is it referring to a sample or population? What is it called? What does it mean? Is it referring to a sample or population? What is it called? What does it mean? Is it referring to a sample or population?

Writing Assignment – Pop Quiz 6. What does this refer to? 7. What does this refer to? 8. What do these two refer to? 9. What does this refer to? What are they called? How are they different What is it called? Use it for sample data or population? What are they called? What do they refer to? How are they different What are they called? How are they different

Writing Assignment – Pop Quiz 10. What does this refer to? What are they called? What do they refer to? How are they different 11. What does this refer to? What are they called? What do they refer to? How are they different

Writing Assignment – Pop Quiz 1. What does this symbol refer to? 2. What does this symbol refer to? 5. What does this symbol refer to? 3. What does this symbol refer to? 4. What does this symbol refer to? What is it called? What does it mean? Is it referring to a sample or population? What is it called? What does it mean? Is it referring to a sample or population? What is it called? What does it mean? Is it referring to a sample or population? What is it called? What does it mean? Is it referring to a sample or population? The standard deviation (population) The mean (population) The mean (sample) The standard deviation (sample) Each individual score sigma population mu x-bar population sample s

6. What does this refer to? 7. What does this refer to? 8. What do these two refer to? 9. What does this refer to? What are they called? How are they different What is it called? Use it for sample data or population? What are they called? What do they refer to? How are they different What are they called? How are they different Variance population sample Sigma squared S squared Deviation scores population sample Sum of squares population sample Degrees of freedom Writing Assignment – Pop Quiz

10. What does this refer to? What are they called? What do they refer to? How are they different 11. What does this refer to? What are they called? What do they refer to? How are they different Variance population sample Standard Deviation population sample

Exam 1 Review