Randomization based on covariates is
A)not of practical importance since individuals are hardly ever assigned in this fashion.
B)dependent on the covariances of the error term (serial correlation).
C)a randomization in which the probability of assignment to the treatment group depends on one of more observable variables W.
D)eliminates the omitted variable bias when using the difference estimator based on Yi = β0 + β1Xi + ui,where Y is the outcome variable and X is the treatment indicator.

Question

Quizplus · Accepted Answer

Randomization based on covariates is a randomization in which the probability of assignment to the treatment group depends on one or more observable variables W. This can improve the precision of treatment effects by reducing the variance of the treatment effect estimator. It also helps in balancing the covariate distributions across treatment groups, thereby reducing bias due to confounding variables.

Randomization Based on Covariates Is