Randomization Based on Covariates Is

question 21

Multiple Choice

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.

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Definitions:

Online Movie Rentals

A service that allows consumers to rent movies digitally over the internet for a limited period.

Price of Movie Tickets

The amount of money charged for admission to a movie screening.

Substitute

An alternative product or service that consumers can turn to if the original product or service becomes unavailable or too expensive.

Ambiguous Effect

An ambiguous effect refers to an outcome or result that is unclear or can have multiple interpretations, often leading to uncertain impacts in economic analyses.