Lecture_20Video_20W10D1_20-_20Categorical_20predictors_20in_20MLR

Categorical Predictor

A variable that can take on one of a limited, and usually fixed, number of possible values, assigning each individual or other unit of observation into a particular group or nominal category.

Dummy Variable

A binary variable created to represent categorical data, typically taking values of 0 and 1 to indicate the absence or presence of a categorical effect.

Reference Category

The category of a categorical variable that serves as a baseline for comparison, often coded as 0 in dummy variable coding.

Binary Predictor

A categorical predictor with only two levels or categories, often coded as 0 and 1.

Expected Value in Regression

The mean value of the response variable, calculated by plugging the predictor values into the regression equation.

Levels of a Factor

Different categories or groups within a categorical variable.

Ordinary Least Squares (OLS) Regression

A type of linear regression that estimates parameters by minimizing the sum of squared differences between observed and predicted values.

Interpretation of Coefficients in Regression

Understanding the meaning of the regression coefficients, which represent the expected change in the response variable for a one-unit change in the predictor, holding other variables constant.

Factor Variable

A categorical variable in statistical modeling, where factors are used to identify categories and levels.

k-non-reference Categories

The number of categories in a categorical variable, excluding the reference category, usually denoted as k-1 when creating dummy variables.