| Peer-Reviewed

Comparison of Tests of Indirect Effect in Single Mediation Analysis

Received: 16 January 2016     Accepted: 4 February 2016     Published: 18 March 2016
Views:       Downloads:
Abstract

This study compares various methods of mediations analysis. Firstly, it compares the two methods of calculating indirect effect which are product of coefficient and difference of coefficients respectively. Secondly, the study compares the three methods of testing the significance of indirect effect vis avis Sobel’s test, Aroian test and Goodman’s test. The differences in these three tests are due to variations in the methods of standard error computation. The findings are discussed. The results show that both methods of product of coefficients and difference of coefficients give approximately the same result. However the product of coefficient gave a slightly higher result. The comparison of test of indirect effect for mediator shows that the tests gave the same result for Sobel’s, Aroian and Goodman test. The study recommended further studies to seek methods of ascertaining the direction of relationship of indirect effect, other than those of the regression models, further studies may be carried out to determine the effect of multicolinearity on mediation results.

Published in American Journal of Theoretical and Applied Statistics (Volume 5, Issue 2)
DOI 10.11648/j.ajtas.20160502.14
Page(s) 64-69
Creative Commons

This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.

Copyright

Copyright © The Author(s), 2016. Published by Science Publishing Group

Keywords

Mediation, Sobels Test, Aroian Test, Goodman Test, Indirect Effect

References
[1] Fairchild, A. J and MacKinnon, D. P. (2009) A general model for testing mediation and moderation effects. Prevention Science, 10, 87-99.
[2] MacKinnon, D. P. (2000). Contrasts in multiple mediator models. In J. Rose, L. Chassin, C. C. Presson, & S. J. Sherman (Eds.), Multivariate applications in substance use research: New methods for new questions (pp. 141-160). Mahwah, NJ: Erlbaum.
[3] Judd CM, Kenny DA. (1981). Estimating the effects of social interventions. Cambridge University Press; Cambridge, England.
[4] Baron, R. M., & Kenny, D. A. (1986). The moderator-mediator variable distinction in social psychological research: Conceptual, strategic and statistical considerations. Journal of Personality and Social Psychology, 51, 1173-1182.
[5] Goodman, L. A. (1960). On the exact variance of products. Journal of the American Statistical Association, 55, 708-713.
[6] Sobel, M. E. (1982). Asymptotic Confidence Intervals For Indirect Effects In Structural equations models. In S. Leinhart (Ed.), Sociological methodology 1982 (pp. 290-312). San Francisco: Jossey-Bass.
[7] Preacher, C. J & Leonardelli, G. J (2010) Calculation for the Sobel test: An interactive calculation tool for Mediation tests, http://quantpsy.org/sobel/sobel.htm.
[8] MacKinnon, D. P., & Dwyer, J. H. (1993). Estimating mediated effects in prevention studies. Evaluation Review, 17, 144-158.
[9] James L. R & J. M Brett (1984). Mediators, moderators, and tests for mediation. J Appl Psychol. 1984; 69: 307–21.
[10] MacKinnon, D. P., Fairchild, A. J., & Fritz, M. S. (2007). Mediation analysis. Annual Review of Psychology, 58, 593-614.
[11] Sherman SJ, Gorkin L. (1980) Attitude bolstering when behavior is inconsistent with central attitudes. J Exp Soc Psychol. Vol. 16: 388–403.
[12] James L. R & J. M Brett (1984). Mediators, moderators, and tests for mediation. J Appl Psychol. 1984; 69: 307–21.
[13] Mackinnon, D. P., Lockwood, C. M., & Williams, J. (2004). Confidence Limits For the indirect effect: Distribution of the product and resampling methods. Multivariate Behavioral Research, 39, 99-128.
Cite This Article
  • APA Style

    Chike Henry Nwankwo, Amechi Henry Igweze. (2016). Comparison of Tests of Indirect Effect in Single Mediation Analysis. American Journal of Theoretical and Applied Statistics, 5(2), 64-69. https://doi.org/10.11648/j.ajtas.20160502.14

    Copy | Download

    ACS Style

    Chike Henry Nwankwo; Amechi Henry Igweze. Comparison of Tests of Indirect Effect in Single Mediation Analysis. Am. J. Theor. Appl. Stat. 2016, 5(2), 64-69. doi: 10.11648/j.ajtas.20160502.14

    Copy | Download

    AMA Style

    Chike Henry Nwankwo, Amechi Henry Igweze. Comparison of Tests of Indirect Effect in Single Mediation Analysis. Am J Theor Appl Stat. 2016;5(2):64-69. doi: 10.11648/j.ajtas.20160502.14

    Copy | Download

  • @article{10.11648/j.ajtas.20160502.14,
      author = {Chike Henry Nwankwo and Amechi Henry Igweze},
      title = {Comparison of Tests of Indirect Effect in Single Mediation Analysis},
      journal = {American Journal of Theoretical and Applied Statistics},
      volume = {5},
      number = {2},
      pages = {64-69},
      doi = {10.11648/j.ajtas.20160502.14},
      url = {https://doi.org/10.11648/j.ajtas.20160502.14},
      eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajtas.20160502.14},
      abstract = {This study compares various methods of mediations analysis. Firstly, it compares the two methods of calculating indirect effect which are product of coefficient and difference of coefficients respectively. Secondly, the study compares the three methods of testing the significance of indirect effect vis avis Sobel’s test, Aroian test and Goodman’s test. The differences in these three tests are due to variations in the methods of standard error computation. The findings are discussed. The results show that both methods of product of coefficients and difference of coefficients give approximately the same result. However the product of coefficient gave a slightly higher result. The comparison of test of indirect effect for mediator shows that the tests gave the same result for Sobel’s, Aroian and Goodman test. The study recommended further studies to seek methods of ascertaining the direction of relationship of indirect effect, other than those of the regression models, further studies may be carried out to determine the effect of multicolinearity on mediation results.},
     year = {2016}
    }
    

    Copy | Download

  • TY  - JOUR
    T1  - Comparison of Tests of Indirect Effect in Single Mediation Analysis
    AU  - Chike Henry Nwankwo
    AU  - Amechi Henry Igweze
    Y1  - 2016/03/18
    PY  - 2016
    N1  - https://doi.org/10.11648/j.ajtas.20160502.14
    DO  - 10.11648/j.ajtas.20160502.14
    T2  - American Journal of Theoretical and Applied Statistics
    JF  - American Journal of Theoretical and Applied Statistics
    JO  - American Journal of Theoretical and Applied Statistics
    SP  - 64
    EP  - 69
    PB  - Science Publishing Group
    SN  - 2326-9006
    UR  - https://doi.org/10.11648/j.ajtas.20160502.14
    AB  - This study compares various methods of mediations analysis. Firstly, it compares the two methods of calculating indirect effect which are product of coefficient and difference of coefficients respectively. Secondly, the study compares the three methods of testing the significance of indirect effect vis avis Sobel’s test, Aroian test and Goodman’s test. The differences in these three tests are due to variations in the methods of standard error computation. The findings are discussed. The results show that both methods of product of coefficients and difference of coefficients give approximately the same result. However the product of coefficient gave a slightly higher result. The comparison of test of indirect effect for mediator shows that the tests gave the same result for Sobel’s, Aroian and Goodman test. The study recommended further studies to seek methods of ascertaining the direction of relationship of indirect effect, other than those of the regression models, further studies may be carried out to determine the effect of multicolinearity on mediation results.
    VL  - 5
    IS  - 2
    ER  - 

    Copy | Download

Author Information
  • Department of Statistics, Nnamdi Azikiwe University, Awka, Nigeria

  • Department of Mathematics and Statistics, Delta State Polytechnic, Ogwashi-Uku, Nigeria

  • Sections