Note: This question is a general question not related to any particular data. What happens to the errors when the regression line is fit on curving data? (Remember the errors are supposed to be normally distributed, have constant variance and not have a pattern, i.e., be independent.)

7) Use the following data to answer the following questions.

Skinfold	Thigh	Midarm	Body Fat
19.5	43.1	29.1	11.9
24.7	49.8	28.2	22.8
30.7	51.9	37	18.7
29.8	54.3	31.1	20.1
19.1	42.2	30.9	12.9
25.6	53.9	23.7	21.7
31.4	58.5	27.6	27.1
27.9	52.1	30.6	25.4
22.1	49.9	23.2	21.3
25.5	53.5	24.8	19.3
31.1	56.6	30	25.4
30.4	56.7	28.3	27.2
18.7	46.5	23	11.7
19.7	44.2	28.6	17.8
14.6	42.7	21.3	12.8
29.5	54.4	30.1	23.9
27.7	55.3	25.7	22.6
30.2	58.6	24.6	25.4
22.7	48.2	27.1	14.8
25.2	51	27.5	21.1

a) Create and display a scatter chart (in Excel) for Body fat (Y axis) and skinfold (x-axis)

b) Create and display a scatter chart (in Excel) for Body fat (Y axis) and thigh (x-axis)

c) Create and display a scatter chart (in Excel) for Body fat (Y axis) and midarm (x-axis)

d) What does each of these charts suggest?

e) Run a correlation for each combination of the data (each independent variable with the dependent variable).

f) What do the correlations for each combination suggest?

Run a multiple regression (in Excel) with body fat as the dependent variable and skinfold, midram and thigh as independent variables. Show the results. Comment on the predictive value of the results.