In the Context of a Controlled Experiment, Consider the Simple

Multiple Choice

In the context of a controlled experiment, consider the simple linear regression formulation Y_i = ?₀ + ?₁X_i + u_i. Let the Y_i be the outcome, X_i the treatment level, and u_i contain all the additional determinants of the outcome. Then

A) the OLS estimator of the slope will be inconsistent in the case of a randomly assigned X_i since there are omitted variables present.
B) X_i and u_i will be independently distributed if the X_i be are randomly assigned.
C) ?₀ represents the causal effect of X on Y when X is zero.
D) E(Y | X = 0) is the expected value for the treatment group.