Introduction to Statistics for the Social Sciences SBS200 - Lecture Section 001, Spring 2018 Room 150 Harvill Building 9:00 - 9:50 Mondays, Wednesdays & Fridays. Welcome http://www.youtube.com/watch?v=oSQJP40PcGI

Lab sessions No Class on Monday No Labs next week Everyone will want to be enrolled in one of the lab sessions No Class on Monday No Labs next week

In nearly every class we will use clickers to answer questions in class and participate in interactive class demonstrations Remember bring your writing assignment forms notebook and clickers to each lecture ..

Schedule of readings Before next exam (February 9) Please read chapters 1 - 5 in OpenStax 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

Start by reading Online supplemental reading 1 (Appendix D) Please read Chapters 1 & 2

Homework Assignment 1 due Wednesday, January 17 Go to D2L - Click on “Content” Click on “Interactive Online Homework Assignments” Complete the first three modules: Levels of Measurement Discrete vs Continuous Variables and Independent and Dependent Variables

By the end of lecture today 1/12/18 Use this as your study guide By the end of lecture today 1/12/18 Constructs versus measurement Operational definitions Validity of operational definitions Reliability of measurements Independent and dependent variables

Announcements What to call me? Dr. Delaney Suzanne Any combination of the above When e.mailing be sure to include all previous e.mail messages 2

Conducting analyses that are relevant and useful starts with measurement designed to decrease uncertainty “Anything can be measured. If a thing can be observed in any way at all, it lends itself to some type of measurement method. No matter how “fuzzy” the measurement is, it’s still a measurement if it tells you more than you knew before.” Douglas Hubbard Author “How to Measure Anything: Finding the value of “Intangibles” in Business”

“A problem well stated is a problem half solved” “Anything can be measured. If a thing can be observed in any way at all, it lends itself to some type of measurement method. No matter how “fuzzy” the measurement is, it’s still a measurement if it tells you more than you knew before.” Douglas Hubbard Author “How to Measure Anything: Finding the value of “Intangibles” in Business” “A problem well stated is a problem half solved” Charles Kettering (1876 – 1958), American inventor, holder of 300 patents, including electrical ignition for automobiles How do we measure the following constructs – define first then we can figure how to measure them? Effectiveness of recycling policy Number of fish in the ocean Improved word of mouth advertising Value of a happy marriage Value of a human life Public image Role of humor in career advancement “It is better to be approximately right, than to be precisely wrong.” - Warren Buffett Examples given by Hubbard Measurements don’t have to be precise to be useful

“A problem well stated is a problem half solved” Charles Kettering (1876 – 1958), American inventor, holder of 300 patents, including electrical ignition for automobiles An operational definition: definition of a construct or characteristic in terms of how it is measured specifically for a particular context How do we measure the following constructs – define first then we can figure how to measure them? Effectiveness of recycling policy Number of fish in the ocean Improved word of mouth advertising Value of a happy marriage Value of a human life Public image Role of humor in career advancement

“Constructs” represent relatively abstract concepts. “Operational definitions” define how constructs are measured. “Measurements” assess observable characteristics or behaviors resulting in a reduction of uncertainty. Data analyses try to describe, predict and explain measurements of behaviors (or characteristics). Examples of measurements: Examples of constructs: humor (how funny a commercial is) laughter/smiles recall test of name of brand memorable (memory for brand name) status of product (BMW, Maserati, Cadillac, VW) rating on scale ??? being in love

How do we measure mental processes? Do people “in love” stay together longer? Mental process = Love, or being in love How would we define “in love” terms of observable behaviors? How about “happiness”?

How do we measure mental processes? Are people more likely to stop at a stop sign if a police officer is present? Defining our measurements How would we define “stop” terms of observable behaviors? How would we define “police officer is present” versus “police officer not present” in terms of observable behaviors? Defining the groups we are comparing

humor (how funny a commercial is) “Constructs” represent relatively abstract concepts. “Operational definitions” define how constructs are measured. “Measurements” assess observable characteristics or behaviors resulting in a reduction of uncertainty. Number of smiles detected during the 90 seconds spot humor (how funny a commercial is) Number of people who correctly recalled brand name after the 90 seconds spot memorable (memory for brand name) Ratings from 1 – 10 “how cool is this car?” status of product (BMW, versus Maserati etc) Size of a person’s big toe…big toed person would be verrry musical!! musicality

Evaluating Operational Definitions: Validity and Reliability Validity: the extent to which a test measures what it intends to measure Reliability: the extent to which a test yields consistent results

Validity and Reliability Validity: the extent to which a your assessment actually measures what it intends to measure Bungy ruler Reliability: the extent to which an assessment yields consistent results Homemade ruler Proper ruler

Validity and Reliability High or Low Reliability? High or Low validity? Validity: the extent to which a your assessment actually measures what it intends to measure Bungy ruler Reliability: the extent to which an assessment yields consistent results Homemade ruler High or Low Reliability? High or Low validity? Proper ruler High or Low Reliability? High or Low validity?

Let’s revisit validity and reliability: Low Validity High Validity Low reliability High reliability Let’s revisit validity and reliability: Remember, reliability is a measure of consistency (or precision) of measurement Validity is a measure of the meaning of the scores Bungee ruler High or Low validity? High or Low Reliability? Homemade ruler Proper ruler High or Low validity? High or Low Reliability? High or Low validity? High or Low Reliability?

Let’s revisit validity and reliability: Low Validity High Validity Low reliability High reliability . Let’s revisit validity and reliability: Remember, reliability is a measure of consistency (or precision) of measurement (how consistent the shot is) Validity is a measure of the meaning of the scores (is the shot aimed in the best direction)

Let’s revisit validity and reliability: Low Validity High Validity Low reliability High reliability . Let’s revisit validity and reliability: Remember, reliability is a measure of consistency (or precision) of measurement (how consistent the shot is) Validity is a measure of the meaning of the scores (is the shot aimed in the best direction)

Let’s revisit validity and reliability: Low Validity High Validity Low reliability High reliability . Let’s revisit validity and reliability: Remember, reliability is a measure of consistency (or precision) of measurement (how consistent the shot is) Validity is a measure of the meaning of the scores (aimed in the best direction)

Let’s revisit validity and reliability: Low Validity High Validity Low reliability High reliability . Let’s revisit validity and reliability: Remember, reliability is a measure of consistency (or precision) of measurement (how consistent the shot is) Validity is a measure of the meaning of the scores (aimed in the best direction)

Let’s revisit validity and reliability: Remember, reliability is a measure of consistency (or precision) of measurement (how consistent the shot is) Validity is a measure of the meaning of the scores (is the shot aimed in the best direction) Low Validity High Validity Low reliability High reliability

Operational definitions, constructs, validity and reliability When evaluating a measurement (operational definition) there may be a tension between the reliability and validity of the measurement humor (how funny a commercial is) status of product (BMW, Maserati, Cadillac, VW) memorable (memory for brand name) Brand loyalty Also watch for the connection between the conclusions about the constructs – and limitations from the operational definition Newsweek Magazine: The Nation’s Top High Schools

Funny?!? I know funny!! ANIMALS!! Operational definition: how you define a concept in terms of how you will measure it What makes a funny commercial?? Funny?!? I know funny!! ANIMALS!! humor Animals are funny – put animals in your commercial !

Operational definition We now have a question: Do animals in a commercial make it funnier? Compare commercial with an animal with one without an animal… Two groups On a scale from 1 – 10 how funny is the commercial? Operational definition “funny” = rating score http://www.youtube.com/watch?v=tKH2oLjQIAA

Two parts to any study: independent vs dependent variable We now have a question: Do animals in a commercial make it funnier? Two parts to any study: independent vs dependent variable Dependent variable: The variable being measured by investigator. The data that is being recorded. What are you measuring Independent variable: The factor that is being manipulated (or compared) by the experimenter. How do your groups differ

How do your groups differ Dependent variable: The variable being measured by investigator. The data that is being recorded. Independent variable: The factor that is being manipulated by the experimenter, (how the two comparison groups differ). Are commercials with animals funnier than commercials without animals? Please rate these commercials (some have animals, some don’t) What are you measuring What is the dependent variable? The rating of the commercials (from 1 – 10) What is the independent variable? Whether or not there is an animal in the commercial How do your groups differ http://www.youtube.com/watch?v=tKH2oLjQIAA

What is an independent vs dependent variable? Dependent variable: The variable being measured by investigator. The data that is being recorded. Independent variable: The factor that is being manipulated by the experimenter. Does not sleeping for three days affect your performance on a memory test? What is the dependent variable? Performance on the memory test What is the independent variable? Whether or not you have slept in last 3 days

What is an independent vs dependent variable? Dependent variable: The variable being measured by investigator. The data that is being recorded. Independent variable: The factor that is being manipulated by the experimenter. Does not sleeping for three days affect your performance on a memory test? How many levels of the IV are there? What is the dependent variable? Performance on the memory test What is the independent variable? Whether or not you have slept in last 3 days

What is an independent vs dependent variable? How many levels of the IV are there? What is an independent vs dependent variable? Dependent variable: The variable being measured by investigator. The data that is being recorded. Independent variable: The factor that is being manipulated by the experimenter. Does gender of patient affect the amount of money spent in nursing homes? What is the dependent variable? Cost of nursing home care What is the independent variable? Gender (man or woman)

What is an independent vs dependent variable? Dependent variable: The variable being measured by investigator. The data that is being recorded. Independent variable: The factor that is being manipulated by the experimenter. Does talking on a cell phone affect your ability to drive? How many levels of the IV are there? What is the dependent variable? Performance on the driving test What is the independent variable? Whether or not you are talking on a cell phone

What is an independent vs dependent variable? How many levels of the IV are there? What is an independent vs dependent variable? Dependent variable: The variable being measured by investigator. The data that is being recorded. Independent variable: The factor that is being manipulated by the experimenter. Does the make of the car affect perceived level of status? Please view these 10 different types of cars and rate how “cool” they are (1 – 3) 1 2 3 What is the dependent variable? not kinda very Rating of “coolness” cool cool cool What is the independent variable? Types of car (10 different types)

Thank you! See you next time!!