For Exercises 37–51, do the following for the indicated data sets from the Section 4.1 exercises:

  1. Calculate the slope and the intercept of the regression line.
  2. State the regression equation in words.
  3. Interpret the value for the slope of the regression line, in terms of the variables from the particular exercise.
  4. Interpret the value for the intercept of the regression line, in terms of the variables from the particular exercise.

Question 4.137

dartsdjia

39. Darts and the Dow Jones. The following table contains a random sample of eight days from the Chapter 3 Case Study data set, indicating the stock market gain or loss for the portfolio chosen by the random darts , as well as the Dow Jones Industrial Average (DJIA) gain or loss for that day .

Darts DJIA
−27.4 −12.8
18.7 9.3
42.2 8.0
−16.3 −8.5
11.2 15.8
28.5 10.6
1.8 11.5
16.9 −5.3
Table 4.52: Source: The Wall Street Journal.

4.2.39

(a) (b) The predicted gain or loss in one day by the portfolio selected by the darts is 1.41 times the gain or loss of the DJIA plus $4.39. (c) For each increase of $1 in the DJIA the predicted value of the portfolio selected by the darts increases by $1.41. (d) The predicted loss or gain in one day by the portfolio selected by the darts for a day when the gain or loss in the DJIA is is $4.39.