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Volume 3, Issue 2, March 2014, Page: 44-48
Direct and Indirect Effects in Dummy Variable Regression
Oyeka I. C. A., Department of Statistics, Nnamdi Azikiwe University, Awka, Nigeria
Nwankwo Chike H., Department of Statistics, Nnamdi Azikiwe University, Awka, Nigeria
Received: Dec. 3, 2013;       Published: Feb. 20, 2014
DOI: 10.11648/j.ajtas.20140302.13      View  3029      Downloads  189
Abstract
This paper proposes and develops the use of the non-cummulative dummy variables of 1’s and 0’s to represent levels of parent independent variables in dummy variable multiple regression models. The regression coefficients obtained using the proposed methods are easier to interprete and clearly understand than the use of the cummulatively coded ordinal dummy variables of 1’s and 0’s that could be used for the same purpose. The proposed method also enables the simultaneous estimation of the total, absolute or overall effect of a parent independent variable as well as its direct effect through its representative dummies and its indirect effect on a given independent variable through the mediation of other parent independent variables in the model was demonstrated. The use of these procedures was illustrated with an example.
Keywords
Dummy Variables, Total Effect, Direct Effect, Indirect Effect, Parent Variables, Mediation Model
To cite this article
Oyeka I. C. A., Nwankwo Chike H., Direct and Indirect Effects in Dummy Variable Regression, American Journal of Theoretical and Applied Statistics. Vol. 3, No. 2, 2014, pp. 44-48. doi: 10.11648/j.ajtas.20140302.13
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