Year 2021, Volume 8 , Issue 2, Pages 279 - 295 2021-06-10

Point and Interval Estimators of an Indirect Effect for a Binary Outcome

Hyung Rock LEE [1] , Jaeyun SUNG [2] , Sunbok LEE [3]

Conventional estimators for indirect effects using a difference in coefficients and product of coefficients produce the same results for continuous outcomes. However, for binary outcomes, the difference in coefficient estimator systematically underestimates the indirect effects because of a scaling problem. One solution is to standardize regression coefficients. The residual from a regression of a predictor on a mediator, which we call the residualized variable in this paper, was used to address the scaling problem. In simulation study 1, different point estimators of indirect effects for binary outcomes are compared in terms of the means of the estimated indirect effects to demonstrate the scaling problem and the effects of its remedies. In simulation study 2, confidence and credible intervals of indirect effects for binary outcomes were compared in terms of powers, coverage rates, and type I error rates. The bias-corrected (BC) bootstrap confidence intervals performed better than did other intervals.
Indirect effects, Binary outcome, Confidence intervals, Bootstrap, Delta
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Primary Language en
Subjects Education, Scientific Disciplines
Published Date June
Journal Section Articles

Orcid: 0000-0002-7415-9466
Author: Hyung Rock LEE (Primary Author)
Institution: The University of Central Arkansas
Country: United States

Orcid: 0000-0001-7461-3123
Author: Jaeyun SUNG
Institution: Lyon College
Country: United States

Orcid: 0000-0002-0924-7056
Author: Sunbok LEE
Institution: Ewha Womans University
Country: South Korea


Publication Date : June 10, 2021

APA Lee, H , Sung, J , Lee, S . (2021). Point and Interval Estimators of an Indirect Effect for a Binary Outcome . International Journal of Assessment Tools in Education , 8 (2) , 279-295 . DOI: 10.21449/ijate.773659