1. What is not an advantage of pooling multiple cross sectional datasets? the ability to estimate how an effect of a variable changed over time increased sample size the ability to estimate time trends conditional on explanatory variables the ability to apply the first differences estimator - 2. The probability of finding a significant result if the hypothesis is true is called consistency O significance level O statistical power minimum detectable effect size 3 Which of these formulas is correct? O a. Selection Bias = Differences in Means / Average Causal Effect O b. Selection Bias = Differences in Means * Average Causal Effect O C. Differences in Means = Average Causal Effect - Selection Bias O d. Differences in Means = Average Causal Effect + Selection Blas