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:

Normal Good

A good for which demand increases as the consumer’s income increases, holding all other factors constant.

Money Income

The total amount of monetary earnings received by an individual or household from various sources, including wages, salaries, and investments.

Electric Automobile

A vehicle that is powered entirely or partially by electricity, offering an alternative to traditional fossil fuel-powered cars.

Complementary Goods

Products that are used together, where the consumption of one enhances the value or demand of the other.