Introduction to Statistics for the Social Sciences SBS200, COMM200, GEOG200, PA200, POL200, or SOC200 Lecture Section 001, Spring 2015 Room 150 Harvill Building 8:00 - 8:50 Mondays, Wednesdays & Fridays.

Instructor:Suzanne Delaney, Ph.D. Office:405 “N” McClelland Hall Phone: Office hours:12:00 – 1:30 Monday and Friday and by appointment Introduction to Statistics in the Social Sciences

Schedule of readings Before next exam (February 13 th ) Please read chapters 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

Everyone will want to be enrolled in one of the lab sessions Labs start next week

Labs this week Gathering Data and Interpreting using Excel Agenda Week 1 - The purpose of this lab is to complete a questionnaire, input data into Excel and explore the results. Step 1. Complete the questionnaire Step 2. Download Excel spreadsheet Step 3. Enter the data for the you and two friends into spreadsheet Step 4. Summarize findings by completing the attached worksheet Using “sort” and “average” functions Step 5. Brain storm as a group and generate one interesting comparison (or hypothesis) you can make using these data Sorting and finding the average

Homework due No homework due Wednesday 1/28/15

Register clickers soon and receive extra credit! (By January 28th)

Measurement: observable actions Theoretical constructs: concepts (like “humor” or “satisfaction”) So far, Operational definitions Validity and reliability Independent and dependent variable Random assignment and Random sampling Within-participant and between-participant design Single blind (placebo) and double blind procedures

Continuous vs Discrete variables Quantitative vs qualitative variables So far, Levels of measurement: Nominal, Ordinal, Interval and Ratio

Question 1 - Population: The entire group of people we want to know about - Sample: The subgroup of people who actually participate in a research study (so we can better understand whole population) Assignment 1 – Chapter 2 Questions 1, 3-7, 9, 10, Question 3 - Dependent variable: The variable being measured by investigator. The data that is being recorded. - Independent variable: The factor that is being manipulated (or compared) by the experimenter. The data: what are you measuring How do your groups differ Question 4 - Statistic: number gathered from a sample - Parameter: number gathered from a population (or is estimated from sample statistic) Question 5 - Discrete: measurements with only whole numbers* - Continuous: possibly infinite number of values between two measurements (e.g. height, weight, and duration) Review

Question 6 - Descriptive: Measurements from whole group you are describing. - Inferential: Measurements of whole group based on subset of the group you are describing, requires inferences about people not actually measured Assignment 1 – Chapter 2 Questions 1, 3-7, 9, 10, Question 7 - Random Sampling: Everyone in population has same chance to be chosen into the sample – sample should reflect population Note: This is different from random assignment, which determines “true” vs “quasi” experiments Review

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” Review

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.

Question 15: What is level of measurement for “brand of shoes”? -Nominal Question 16: What is level of measurement for “temperature”? -Kelvin is ratio -Fahrenheit is interval Question 17: What is level of measurement for ___ -time to finish a race is ratio -1 – 7 ranking is interval -types of drinks is nominal -level of confidence is ordinal -E.g. Not confident – a little confident – very confident

Question 18: a.How many numbers do we have? Find “N” N = 7 x 1 = 72 x 2 = 29 x 3 = 10 x 4 = 49 x 5 = 22 x 6 = 58 x 7 = 63 x 1 = 72 x 2 = 29 x 3 = 10 x 4 = 49 x 5 = 22 x 6 = 58 x 7 = 63 b. What do we get if we add up all the numbers? Find Σx Σx = 303 c. What do we get if we square each number then add them up? Find Σx 2 Σx = 16,343 d. What do we get if add up the numbers then square it? Find ( Σx) 2 Σx = 91,809 e. What do we get if we subtract 6 from each number then add them up? Find Σ(x - 6) Σ(x - 6) = 261 f. What do we get if we add up the numbers then add 12? Find Σx + 12 Find Σx + 12 = 315

Question 19: What is level of measurement for “time to react”? -Ratio Question 20: What is level of measurement for “level of anxiety”? -Ordinal or Interval or Ratio Question 21: What is level of measurement for “math ability”? -Ratio Question 22: What is level of measurement for “Fahrenheit”? -Interval Question 23: What is level of measurement for “birth weight”? -Ratio Question 24: What is level of measurement for “sex of child”? -Nominal Question 25: What is level of measurement for “number of students”? -Nominal “number of students”? - ratio “ranking of beauty”? - ordinal “ranking of poems”? - ordinal “anxiety level”? – ordinal, interval or ratio

First homework - due today

Review of Homework Worksheet

Homework review You are looking to see if “class standing” affects the “level of sales”. Independent variable (IV):______________ Number of levels of IV: ________________ (how many means?) Quasi or True experiment:______________ Dependent variable: __________________ Between or within participant design: ______________ In this study, what is the operational definition of “class standing”? In this study, what is the operational definition of “level of sales”? Class standing Level of sales 4 Quasi Between Classification based on units earned Number of bags of peanuts sold

Homework review You are looking to see whether “type of program” has an effect on “body transformation”. Please identify the following variables: Independent variable (IV):______________ Number of levels of IV: _______________ (how many means?) Quasi or True experiment:______________ Dependent variable: __________________ Between or within participant design: ______________ What is the operational definition of “type of program”? What is the operational definition of “body transformation”? Type of program Body transformation 2 True Between Type of program = type of diet (regular versus programmatic diet) Body transformation = number of pounds lost

Homework review You are looking to see which driving choice is most efficient. So you ask each driver to drive each of the three routes and time themselves on how long it takes. Please identify the following variables: Independent variable (IV):______________ (how many means) Number of levels of IV: ________________ Dependent variable: __________________ Between or within participant design: ______________ What is the operational definition of “driving efficiency”? What is the operational definition of “driving choice”? Type of route driving efficiency 3 Within Driving efficiency = travel time (measured in minutes) Driving choice = route taken

Homework review

Notice that the operational definition of each construct matters

Homework review gender 2 quasi salary between nominal ratio

Name of City Quasi- experiment 3 Between Temperature Nominal Interval

Homework review city 3 quasi temperature between nominal interval Must be complete and must be stapled Hand in your homework

On a the top half of a writing assignment form please generate two examples of categorical data and two examples of numerical data Categorical data (also called qualitative data) - a set of observations where any single observation is a word or a number that represents a class or category Numerical data (also called quantitative data) - a set of observations where any single observation is a number that represents an amount or count Please note we’ll use the bottom half for something else

What are the four “levels of measurement”? Interval data - measurable differences in amount, equal intervals Ordinal data - order, rankings, differences in degree Ratio data - measurable differences in amount with a “true zero” Look at your examples of qualitative and quantitative data. Which levels of measurement are they? Nominal data - classification, differences in kind, names of categories Categorical data Numerical data