A Researcher Had a Categorical Variable That They Wanted to Include

question 11

Multiple Choice

A researcher had a categorical variable that they wanted to include as a predictor in a regression equation. The researcher was trying to predict the success of a back pain intervention, and the categorical variable was the duration of the back pain prior to treatment, with four categories: less than 6 months, 6-12 months, 1-2 years, more than 2 years. They needed to code these variables into dummy variables for the regression using less than 6 months as their control category. Which of the following represents the correct coding scheme?

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Definitions:

Dictionary

A reference book or electronic resource containing words of a language, usually alphabetically arranged, with definitions, etymologies, phonetics, and other information.

Per Unit Tax

A tax applied on a product based on a fixed amount per unit sold, impacting the supply curve by shifting it upward or to the left.

Monopolist

An individual or firm that is the sole provider of a particular product or service, possessing significant market power to determine prices and output levels.

Price Increase

The rise in the cost of goods or services over time, typically reflected in higher consumer prices.