For a football game in the National Football League, let y = difference between number of points scored by the home team and the away team (so, y > 0 if the home team wins). Let x be the predicted difference according to the Las Vegas betting spread. For the 768 NFL games played between 2003 and 2006, MINITAB results of a regression analysis follow.1
a. Explain why you would expect the true y €“intercept to be 0 and the true slope to be 1 if there is no bias in the Las Vegas predictions.
b. Based on the results shown in the table, is there much evidence that the sample fit differs from the model μy = α + βx with α = 0 and β = 1? Explain.

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Predictor Coef SE Coef P Cons tant-0.40220.5233-0.770.442 LasVegas 1.0251 0.0824 12.44 0.000 R-Sq = 16.8%