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1. 2.194 Comparing Global Internet Connections. In Exercise 2.120we discuss a study in which the Nielsen Company measured connectionspeeds on home computers in nine different countries in order todetermine whether connection speed affects the amount of timeconsumers spend online. Table 2.29 (by exercise 2.194 in thetextbook) shows the percent of Internet users with a “fast”connection (defined as 2Mb or faster) and the average amount oftime spent online, defined as total hours connected to the Web froma home computer during the month of February 2011. The data arealso available in the dataset GlobalInternet. We are interested inlooking at whether the percent of Internet users with a fastinternet connection predicts the number of hours spentonline.
   
   1. What is the explanatory variable? What is the responsevariable? Is each categorical or quantitative?
      
      
      
      
      
   2. What would a positive association mean between these twovariables? Briefly explain why a positive relationship might makesense in this context.
      
      
      
      
      
      
      
      
      
   3. What would a negative association mean between these twovariables? Briefly explain why a negative relationship might makesense in this context.
      
      
      
      
      
      
      
   4. Make a scatterplot with regression line, using connection speedas the explanatory variable and time online as the responsevariable. Include a screen shot of your Statkey output with yourhomework submission. What is the correlation?
      
      
   5. Are there any outliers? If so, indicate the country associatedwith each outlier and describe the characteristics that make it anoutlier for the scatterplot.
      
   6. Eliminate the outliers you identified, and generate anotherscatterplot with regression line. Is the correlation stronglyaffected by the outliers?
      
      
      
      
   7. Find the regression equation for these variables with theoutliers removed. Include a screen shot of your Statkey scatterplotwith regression line with your homework submission, and write theregression equation here.
   8. Interpret the slope of the regression line in context. Rememberthat an interpretation must include a number and units, in asentence that explains the meaning.
   9. Use the regression line to predict the number of hours spentonline in Febrary 2011 in a country in which 65% of Internet usershave a fast connection. Show your calculations.