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:

Zygote

The initial cell formed when two gamete cells are joined by means of sexual reproduction, containing genetic information from both parents.

Gamete

A mature sexual reproductive cell, such as a sperm or egg, that unites with another cell to form a new organism.

Random Chromosome Alignment

The process during meiosis where chromosomes arrange themselves randomly at the equatorial plate, which contributes to genetic variation.

Maternal Grandmother

The mother of one's mother, a key family member often involved in the upbringing and cultural transmission within families.