PSYCH 240 Lecture Notes - Lecture 4: Scatter Plot, Dependent And Independent Variables, Standard Deviation

• School: UMASS-Amherst
• Department: Psychology & Brain Sciences
• Course: PSYCH 240
• Professor: Staub Adrian

Document Summary

Scatterplots are good visual displays of the relationship between quantitative variables. How to decide what goes on each axis: The one on the x-axis is seen as the explanatory variable, and the one on the y-axis is seen as the response variable. Linear: points fall roughly along a straight line. Numerical measures of the relationship between two variables. Correlation coef cient (r): measures the strength of the relationship. Values near -1 or 1 have a strong association, and if they are closer to 0, then there"s a weak association. Negative values = negative association, positive values = positive association. Measures the strength of the linear association between two variables. There are associations where x indirectly affects y. A variable that can in uence both an x and y variable common cause . Least squares regression line (lsrl) - the line that best captures the relationship between two variables.