Chapter 20, Problem 22E

Drug use 2013 The 2013 World Drug Report investigated the prevalence of drug use as a percentage of the population aged 15 to 64. Data from 32 European countries are shown in the following scatterplot and regression analysis. (World Drug Report, 2013. www.unodc.org/unodc/en/data-and-analysis/WDR-2013.html)

Response variable is Cocaine

R-squared = 25.8%

s = 0.7076 with 32 – 2 = 30 degrees of freedom

1. a) Explain in context what the regression says.
2. b) State the hypothesis about the slope (both numerically and in words) that describes how use of cannabis is associated with other drugs.
3. c) Assuming that the assumptions for inference are satisfied, perform the hypothesis test and state your conclusion in context.
4. d) Explain what R-squared means in context.
5. e) Do these results indicate that cannabis use leads to the use of harder drugs? Explain.