Because administering the creativity test is much cheaper, the researcher wants to know if the CREATE score is a good substitute for the more expensive TASK score. The task score is the mean time taken to perform several hand – eye coordination tasks. EXAMPLE SIMPLE LINEAR REGERSSION IN SASĪ random sample of fourteen elementary school students is selected from a school, and each student is measured on a creativity score ( X ) using a new testing instrument and on a task score ( Y ) using a standard instrument. Produces separate regression analyses for each value of the BY variable. Specifies the variable to be predicted ( dependentvar ) and the variable Using SAS PROC REG for Simple Linear RegressionĭATA= datsetname which specifies the dataset. Specifically, the hypotheses are:Ī low p - value for this test (say, less than 0.05) indicates significant evidence to conclude that the slope of the line is not 0 - that is, knowledge of X would be useful in predicting Y. The null hypothesis that there is no predictive linear relationship between the two variables is that the slope of the regression equation is zero.
Where a and b are the least - squares estimates of α and β. The regression line that SAS calculates from the data is an estimate of a theoretical line describing the relationship between the independent variable ( X ) and the dependent variable ( Y ).A simple linear regression analysis is used to develop an equation (a linear regression line) for predicting the dependent variable given a value ( x ) of the independent variable.
Where the dependent variable ( dependentvar ) is the measure you are trying to predictĪnd the independent variable ( independentvar ) is your predictor. As in the ANOVA procedure discussed in Chapter 9, the MODEL statement has the following form: Notice that the MODEL statement is used to tell SAS which variables to use in the analysis. The following SAS PROC REGĬode produces the simple linear regression equation for this analysis: That is, you could determine whether increased exposure to asbestos is predictive of diminished FVC. For example, in a study of factory workers you could use simple linear regression to predict a pulmonary measure, forced vital capacity (FVC), from asbestos exposure. Simple linear regression is used to predict the value of a dependent variable from the value of an independent variable.
Writing sas code linear regression software#
Include how-to instructions for SAS Software Pharmaceutical, Clinical Trials, Marketing or Scientific Research. Interpretation of standard statistical analysis techniques for Medical, These SAS statistics tutorials briefly explain the use and
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