STAT 101 Study Guide - Midterm Guide: Dependent And Independent Variables, Standard Deviation, Conditional Probability
Document Summary
Mean/median identify the center of a histogram. Locate the position of an observation in a bell- shaped distribution. 68% 2/3 of data lie within 1 sd of the mean. 95% of data lie within 2 sd of the mean. 99. 7% of data fall within 3 sd of mean. Shape of a distribution: mode, uniform, symmetric, tails, skewness. Marginal distributions: the totals for rows and columns conditional distributions: individual rows and columns if conditional distribution differs from marginal distribution, the two variables are associated. Simpson"s paradox: exists when the proportion of an event conditional upon some factor is always greater than some other event, but marginally those proportions reverse. Regression line: y = a + b*x a= y- b*x b= r* Interpretation of slope: describes how differences in the explanatory variable (x) associate with differences in the response (y)
