Walks the per-node fits inside a piecewiseSEM::psem() object and
delegates each to symbolize.<class>(), returning a symbolized_psem
collator that bundles the per-node symbolized_model objects, the
node names (response variables, in declared order), and any declared
%~~% residual covariance arcs.
Usage
# S3 method for class 'psem'
symbolize(fit, symbols = NULL, units = NULL, context = NULL, ...)Arguments
- fit
A
piecewiseSEM::psem()fit.- symbols
Optional named character vector mapping variable names to user-supplied LaTeX symbols, e.g.
c(body_mass = "W_i", temperature = "T_i").- units
Optional named character vector mapping variable names to units, e.g.
c(body_mass = "g", temperature = "C").- context
Optional short character description of the model, e.g.
"avian body-size location-scale model".- ...
Reserved for method-specific extra arguments.
Value
A symbolized_psem object with elements parts (list of
per-node symbolized_models, named by response variable),
node_names (character), cov_arcs (character, declared %~~%
arcs as "a ~~ b" strings), and metadata.
Details
Each node is mean-structure only by construction. For distributional
(location-scale) or multivariate structural equations, use the
drm_sem path in the drmSEM package.
References
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. doi:10.1111/2041-210X.12512
Shipley, B. (2009). Confirmatory path analysis in a generalized multilevel context. Ecology, 90(2), 363-368. doi:10.1890/08-1034.1
See also
The keeley dataset (Grace & Keeley 2006) bundled with
piecewiseSEM, used in vignette("symbolizer-sem").