F IL E A multiple regression model is used to predict an NFL team's winning record (Win). For the explanatory variables, the average rushing yards (Rush) and the average passing yards (Pass) are used to capture offense and the average yards allowed are used to capture defense. A portion of the data for the 2009 NFL season is given below; the complete data, labeled Football, can be found on the text website.

Team Win (%) Rush Pass Yards Allowed Arizona Cardinals 62.50 93.40 251.00 346.40 Atlanta Falcons 56.30 117.21 223.19 348.90 Washington Redskins 25.00 94.38 218.13 319.70 SOURCE: NFL website.

a. Estimate the model: Win = β 0 + β 1 Rush + β2 Pass +

β 3Yards Allowed + ε .

b. Conduct a test at the 10% significance level to determine whether the impact of Rush is different from that of Pass in explaining Win, or β1 ≠ β 2 . Provide the relevant steps.