Definicja dummy variable
Dummy variables are variables that take values of either 0 or 1, and are used to indicate the presence or absence of one or more qualitative characteristics. In other words, dummy variables quantify or measure qualitative variables that are not measurable except by signaling whether a characteristic is absent or present. The coefficient of a dummy variable in a regression equation shows the average effect on the dependent variable when the dummy variable assumes the values 1. There are three classic applications of dummy variables:
1) Detect seasonal patterns or seasonality associated with the dependent variable.
2) Adjust the dependent variable's history for aberrations or outliers.
3) Measure the effect of qualitative variables on the dependent variable.
The benefits of using dummy variables are:
1) They enable other independent variables to account more accurately for normal sales variances during unusual periods (such as hotter than normal weather conditions due to El Nińo).
2) They enable nonmetric qualitative data to be transformed into metric quantitative data and used as independent variables.
In Demand Planning, you can define dummy variables as part of multiple linear regression (MLR).
Słownik i definicje SAPa na D.