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Explain why or why not in each case. Which of the following are consequences of

ID: 3171477 • Letter: E

Question

Explain why or why not in each case.

Which of the following are consequences of heteroscedasticity? A. The OLS estimators 0 are inconsistent. B. The usual F statistic no longer has an F distribution. C. The OLS estimators 0 are no longer BLUE. Explain why or why not in each case. Consider the following model based on cross-sectional data for questions 2 and 3. wage = constant + beta_1* education_i + beta_2 * experience_i + mu_i Where:| wage = the hourly wage for person i education = the number of years of education for person i experience = the number of years of working experience for person i

Explanation / Answer

1)

A) We cannot say they are inconsistent.

Inconsistency is due to correlation between error and regressors.

eg: To omitted variables, measurement error in the regressors, are but not to conditional heteroskedasticity.

B) Yes, it is no longer F distribution.

We need both A.MLR5 (conditional homoskedasticity) and A.MLR6 (errors conditionally normal) for the F-statistic to have a Fisher-F distribution under the null .

C) OLS are blue indicates they are best and efficient among all linear unbiased estimators. Hence the claim it is not BLUE is true