1) True or False? In a simple regression with the sample size being 20, we find...

1) True or False? In a simple regression with the sample size being 20, we find the sum of squared residuals to be 1800, then the mean square error of the regression equals 10.

2) True or False? A local trucking company fitted a regression to relate the travel time (days) of its shipments as a function of the distance traveled (miles). The fitted regression is Time = −7.126 + 0.0214 Distance, based on a sample of 20 shipments. The estimated standard error of the slope is 0.0053. In a right-tailed test for a nonpositive slope at ? ൌ 0.01, we fail to reject the null hypothesis that the slope is no more than zero.

3) True or False? Smaller mean square errors lead to wider prediction intervals for Y.

4)True or False? If there is non-normality of errors, the OLS estimators of the slope and intercept will be biased and inconsistent.

5) True or False? In a runs test with 80 residuals, we find there are 60 zero centerline crossings. It suggests there is negative autocorrelation for the errors

6) True or False? In a simple regression with 25 observations, a leverage statistic of 0.1 would indicate the corresponding observation has high leverage.

7) True or False? A studentized residual equal to -2.5 indicates the original residual is unusual.

Expert Solution

orchestra answered 2 years ago

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