Regression:The word ‘regression’ is used to denote estimation or prediction of the average value of one variable for a specified value of the other variable. In regression analysis, there are two types of variables. The variable, whose value is or is to be influenced or is to be predicted, is called dependent variable and the variable which influences the values or is used for prediction is called independent variable. The height and weight of children are correlated. In this case, a change in the independent variable, height of the child will cause a change in the dependent variable, weight of the child. Here, the change of dependent variable with respect to change in the independent variable is known as Regression.
Examples : 1. A researcher may find that intelligence scores of individuals may be predicted from physical factors such as birth order, birth weight and length of gestation along with certain hereditary and external environmental factors.
- Length of stay in a chronic disease hospital may be related to the patient’s age, marital status, sex, and income, not to mention the obvious factor of diagnosis.
- The response of an experimental animal to some drug may depend on the size of the dose and the age and the weight of the animal.
- A nursing supervisor may be interested in the strength of the relationship between a nurse’s performance on the job, score on the state board examination, and scholastic record
- A hospital administrator studying admissions from various communities served by the hospital may be interested in determining what factors seem to be responsible for differences in admission rates.
