semEff provides functionality to automatically calculate direct, indirect, and total effects for ‘piecewise’ structural equation models, comprising lists of fitted models representing structured equations (Lefcheck, 2016; Shipley, 2000, 2009). Confidence intervals are provided via bootstrapping.
Currently supported model classes are
You can install the released version of
semEff from CRAN with:
And the development version from GitHub with:
The primary function is
semEff(), which returns an object of class
"semEff" with associated
summary() methods. Everything can technically be accomplished in a single call to
semEff(); however, since bootstrapping is employed to generate resamples for confidence intervals (via
bootEff()), it is usually preferable to save these estimates separately prior to calling
semEff() – allowing more flexibility and saving time if/when recalling the function.
Package functions are well-documented and most include some short examples. In addition, see the following vignettes for some longer demonstrations:
Lefcheck, J. S. (2016). piecewiseSEM: Piecewise structural equation modelling in R for ecology, evolution, and systematics. Methods in Ecology and Evolution, 7(5), 573–579. https://doi.org/10/f8s8rb
Shipley, B. (2000). A New Inferential Test for Path Models Based on Directed Acyclic Graphs. Structural Equation Modeling: A Multidisciplinary Journal, 7(2), 206–218. https://doi.org/10/cqm32d
Shipley, B. (2009). Confirmatory path analysis in a generalized multilevel context. Ecology, 90(2), 363–368. https://doi.org/10/bqd43d