Introduction to Statistics for the Social Sciences SBS200 - Lecture Section 001, Fall 2016 Room 150 Harvill Building 10:00 - 10:50 Mondays, Wednesdays & Fridays. Welcome http://www.youtube.com/watch?v=oSQJP40PcGI
Lab sessions Everyone will want to be enrolled in one of the lab sessions Labs start Today
Schedule of readings Before next exam (September 23rd) 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
Homework Assignment 2 due Wednesday, August 31st Go to D2L - Click on “Content” Click on “Interactive Online Homework Assignments” Complete the next two modules: Independent and dependent variables Quasi- vs True Experiments Between vs Within Participant Designs
By the end of lecture today 8/29/16 Use this as your study guide By the end of lecture today 8/29/16 Introduction to Project 1 Continuous versus discrete Levels of Measurement: Nominal, Ordinal, Interval and Ratio
One group gets cocoa extract capsules Other group Placebo capsules Measure likelihood of heart attacks What is the independent variable? What is the dependent variable? How many levels are there of the IV? “Between” or “within” participant design? Placebo
Placebo (single blind) versus double blind procedure Single blind procedure (example: use of placebo) Double blind procedure What about experimenter bias?
Project 1 - Likert Scale (summated scale) - Correlation (scatterplots) - Comparing two means (bar graph)
Likert Scale is always a “summated scale” with multiple items. All items are measuring the same construct. The score reflects the sum of responses on a series of items. - miniquiz (like Cosmo - ask several questions then sum responses) - For example, several questions on political views (coded so that larger numbers mean “more liberal”) 1. Lower taxes and a smaller government will improve the standard of living for all. agree 1 --- 2 --- 3 --- 4 --- 5 disagree 2. Marriage should be between one man and one woman agree 1 --- 2 --- 3 --- 4 --- 5 disagree 3. Evolution of species has no place in public education agree 1 --- 2 --- 3 --- 4 --- 5 disagree
Likert Scale is always a “summated scale” with multiple items. All items are measuring the same construct. The score reflects the sum of responses on a series of items.
“Serious Gamer” Score “Serious Gamer” Score “Serious Gamer” Score Time One positive correlation One negative correlation Comparing Two means “Serious Gamer” Score “Serious Gamer” Score “Serious Gamer” Score Time Studying Age Gender
Project 1 - Likert Scale (summated scale) - Correlation (scatterplots) - Comparing two means (bar graph)
Scatterplot displays relationships between two continuous variables Correlation: Measure of how two variables co-occur and also can be used for prediction Range between -1 and +1 The closer to zero the weaker the relationship and the worse the prediction Positive or negative
Positive correlation: as values on one variable go up, so do values Positive correlation: as values on one variable go up, so do values for the other variable Negative correlation: as values on one variable go up, the values for the other variable go down Height of Mothers by Height of Daughters Height of Mothers Positive Correlation Height of Daughters
Positive correlation: as values on one variable go up, so do values Positive correlation: as values on one variable go up, so do values for the other variable Negative correlation: as values on one variable go up, the values for the other variable go down Brushing teeth by number cavities Brushing Teeth Negative Correlation Number Cavities
Project 1 - Likert Scale (summated scale) - Correlation (scatterplots) - Comparing two means (bar graph)
Thank you! See you next time!!