Is the width of a tornado related to the amount of distance for which the tornado is on the ground? Go www.pearsonhighered.com/sullivanstats to obtain the data file 4_3_31 using the file format of your choice for the version of the text you are using. The data represent the width (yards) and length (miles) of tornadoes in the state of Oklahoma in 2013.

(a) What is the explanatory variable?

(b) Explain why this data should be analyzed as bivariate quantitative data.

(c) Draw a scatter diagram of the data. What type of relation appears to exist between the width and length of a tornado?

(d) Determine the correlation coefficient between width and length.

(e) Is there a linear relation between a tornado's width and its length on the ground?

(f) Find the least-squares regression line.

(g) Predict the length of a tornado whose width is 500 yards.

(h) Was the tornado whose width was 180 yards and length was 1.9 miles on the ground longer than would be expected?

(i) Interpret the slope.

(j) Explain why it does not make sense to interpret the intercept.

(k) What proportion of the variability in tornado length is explained by the width of the tornado?

(l) Plot residuals against the width. Does the residual plot suggest the two variables are linearly related?

(m) Draw a boxplot of the residuals. Are there any outliers?

(n) A major tornado was 4576 yards wide that had a length of 16.2 miles. Is this an influential tornado? Explain.