Correlation and Regression statistics homework help

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 Suppose your favorite bar conducts a 6-month experiment to determine the effect 4of advertising on sales revenue. The bar increased its advertising by $1,000 each month and obtained the following results,

                         Month  Advertising Expenditure (in $1,000)  Sales Revenue (in $10,000)

                            1                         1                                                   1

                            2                          2                                                   1 

                            3                           3                                                  2

                            4                           4                                                   2

                            5                           5                                                   4

                            6                            6                                                   3

(a) Which is the explanatory variable and which is the response variable?

(b) By hand, draw a scatter-plot for the data.

(c) By hand, compute all three sums of squares.

(d) By hand, compute the correlation coefficient and describe the association in terms of direction and strength. Do the data appear linear?

(e) Find and state the sample least-squares regression line with proper notation.

(f) Use the model to predict the sales revenue if the bar spends 4.5 thousand dollars for advertising in a month. Express your answer in thousands of dollars.

(g) What should the sum of the residuals add up to? Explain why.

(h) Compute the coefficient of determination, R2, and write a statement about what it means in terms of the model.