The Steps of Correlational Survey Research Technique
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2 Prediction Design
A second type of correlational design is called a prediction design. The purpose of this design is to identify variables that can effectively predict some
outcome or criterion. The variable being predicted is called the criterion variable, and the variable or variables being used to predict the criterion are called
predictors. When a study involves only two variables, the predictive relation is estimated with a statistical procedure called simple linear regression. When more
than one predictor variable is used to predict a criterion, the analysis is called multiple regression. This is an extremely powerful statistical procedure that can
estimate the collective as well as the individual contributions of all predictor variables. This analysis makes it is possible to develop not only an effective
prediction, but also an efficient one. While the general characteristics of prediction designs are similar to those
for relational designs, they differ several important ways. These are as follows. a
Two or more variables are collected from each individual in the sample. b
Data for the predictor variables is typically collected prior to that of the criterion variable.
c The data is analyzed as a single group.
d A correlation coefficient – typically a multiple R – is reported and discussed in
terms of its strength, direction, and statistical significance. e
The contribution of each predictor variable is examined in terms of its unique contribution to the prediction of the criterion variable.
A regression coefficient – b
i
– is reported for each predictor variable and is discussed in terms of its significance to the prediction of the criterion variable. In
38 some cases, a specific analysis is used to evaluate the efficiency and effectiveness
of the predictor variables. This is called stepwise regression and results in the prediction of the criterion variable in which the effectiveness of each predictor
variable is examined for redundancy with other predictors. Those predictors that do not uniquely contribute to the prediction are eliminated.
f A regression equation is produced which can be used to predict the criterion
variable from data collected only on the predictor variables. g
Interpretations from the statistical results are drawn about the predictive process.