POLS 207 Lecture Notes - Lecture 2: Scientific Method, Empirical Relationship, Heat Map
6 Nov 2017
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Document Summary
Scatterplots put two variables on the map simultaneously. Doubles the information available from a heat map. Improves ability to check for possible relationships in the data. Relationship or non relationship between observable characteristics of two different objects of investigation. Value indicates degree to which the data reflects a linear relationship. Higher r means tighter grouping along the trend; fewer outliers. Higher r is read as a stronger relationship. Plus and minus signs show the direction of the relationship (slope) Negative values point to a negative relationship. R = -1 means: a perfect negative empirical relationship. R = +1 means: a perfect positive empirical relationship. Two variables are correlated only if the r coefficient meets or beats a set threshold. Criteria for acceptably strong correlation coefficient is normally calculated using the number of observations available. For this course: minimum r threshold to achieve correlation = 0. 3.
