10.60 State and college binge drinking. Excessive consumption of alcohol is associated with numerous adverse consequences. In one study, researchers analyzed binge-drinking rates from two national surveys, the Harvard School of Public Health College Alcohol Study (CAS) and the Centers for Disease Control and Prevention’s Behavioral Risk Factor Surveillance System (BRFSS).24 The CAS survey was used to provide an estimate of the college binge-drinking rate in each state, and the BRFSS was used to determine the adult binge-drinking rate in each state. A correlation of 0.43 was reported between these two rates for their sample of n = 40 states. The college binge-drinking rate had a mean of 46.5% and standard deviation 13.5%. The adult binge-drinking rate had a mean of 14.88% and standard deviation 3.8%.

  1. (a) Find the equation of the least-squares line for predicting the college binge-drinking rate from the adult binge-drinking rate.

  2. (b) Give the results of the significance test for the null hypothesis that the slope is 0. ( Hint: What is the relation between this test and the test for a zero correlation?)