MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1)…

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Which of the following is true for instrument? A) The set of instruments are said to be weak when the number of instruments are stricly superion to the number of endogenous regressors. B) A valid instrument should be an exogenous variable. C) When the first stage F-statistic is less than 10, then the set of instruments are not weak. D) Anderson-Rubin-based confidence intervals are not valid for weak instruments. 2) When analyzing time series, 2) A) The first difference of a random walk is not stationary. B) The Augmented-Dickey Fuller (ADF) test can be used to detect the presence of correlation in our data. The Quandt Likelihood Ratio (QLR) statistic can be used to test for a break only when the break C) date is known. D) The Chow test can be used to test for a break when the break date is known. 3) One main advantage of using panel data over cross sectional data is that it, 3) A) allows you to analyze behavior across time but not across entities. B) allows you to have heteroskedasticity-robust standard errors. C) allows you to control for some types of omitted variables without actually observing them. D) allows you to look up critical values in the standard normal distribution.