Estimate Sobel's (1982) Test for Mediation

Description

Estimate Sobel's (1982) indirect test for mediation. The function provides an estimate of the magnitude of the indirect effect, Sobel's first-order estimate of the standard error associated with the indirect effect, and the corresponding z-value. The estimates are based upon three models as detailed on page 84 of MacKinnon, Lockwood, Hoffman, West and Sheets (2002).

Usage

1
sobel(pred,med,out)

Arguments

pred

The predictor or independent variable (X).

med

The mediating variable (M).

out

The outcome or dependent variable (Y).

Value

Mod1: Y~X

A summary of coefficients from Model 1 of MacKinnon et al., (2002).

Mod2: Y~X+M

A summary of coefficients from Model 2 of MacKinnon et al., (2002).

Mod3: M~X

A summary of coefficients from Model 3 of MacKinnon et al., (2002).

Indirect.Effect

The estimate of the indirect mediating effect.

SE

Sobel's (1982) Standard Error estimate.

z.value

The estimated z-value.

N

The number of observations used in model estimation.

Author(s)

Paul Bliese paul.bliese@moore.sc.edu

References

MacKinnon, D. P., Lockwood, C. M., Hoffman, J. M., West, S. G., Sheets, V. (2002). A comparison of methods to test mediation and other intervening variable effects. Psychological Methods, 7, 83-104.

Sobel, M. E., (1982). Asymptotic confidence intervals for indirect effects in structural equation models. In S. Leinhardt (Ed.), Sociological Methodology 1982 (pp. 290-312). Washington, DC: American Sociological Association.

Examples

1
2
3
4
5
data(bh1996)

#A small but significant indirect effect indicates leadership mediates
#the relationship between work hours and well-being.
sobel(pred=bh1996$HRS,med=bh1996$LEAD,out=bh1996$WBEING)

Want to suggest features or report bugs for rdrr.io? Use the GitHub issue tracker.