POLS 207 9TH Edition Lecture 5 Outline of Last Lecture II Comparing states and Communities A Physical demographic B Wealth C Social problem D Coping with social problems III Map explanations IV Innocence project V Chapter 2 VI Scatter plots and correlations Outline of Current Lecture VII Empirical relationships on graphs a Minimum strength threshold b Direction of relationship c Possible interpretations d Issues in empirical relationships VIII Importance of measurements IX Motion graphs X Exam notes Current Lecture Empirical relationships in scatterplots and correlations o 1 relationships are a perfect relationship very rare o Minimum strength threshold If you score above 0 3 you are a relationship If you score below there is no relationship o Direction of relationship Shows whether relationship is positive or negative o Possible interpretations Cannot interpret there is a cause and effect o Texas Steepness of the line shows strong weak relationship Progression line is the predicted level Way below above the progression line is called an outlier These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute R Pearson correlation measure steepness slope of line o 3 4 weak o 5 7 moderate o 7 9 strong STUDY GRAPHS IN FIRST 2 CHAPTERS Issues in an empirical relationship o Measurement o Variable linkage o Is there a relationship Issues if there is an empirical relationship o Casual relationship o Spurious relationship Relationship that the Pearson correlations is strong but in reality there is no relationships at all Ex consumption of ice cream goes up the number of murders go up Importance of measurements o Rates not raw numbers o Rates have numerators and denominators o Also control for inflation over time o Proper linkage of cause and effect Motion graphs o Animated scatterplots o Add information about time EXAM TUESDAY o o o o o o 1 HOUR EXAM 50 QUESTIONS READ CHAPTER 1 9TH EDITION STUDY MINIMUM OF 2 TIMES 12 15 PAGES AN HOUR NOT ONLY NOTES READ BOOK BECAUSE NOTES DIDN T COVER IT ALL LOOK AT CORRELATIONS GRAPHS KNOW RELATIONSHIPS FOR EACH