Return the estimate of Delta_Med in a 'delta_med'-class object.
Usage
# S3 method for class 'delta_med'
coef(object, ...)
Arguments
- object
The output of
delta_med()
.- ...
Optional arguments. Ignored.
Details
It just extracts and
returns the element delta_med
in the output of delta_med()
,
the estimate of the Delta_Med
proposed by Liu, Yuan, and Li (2023),
an \(R^2\)-like measure of indirect
effect.
References
Liu, H., Yuan, K.-H., & Li, H. (2023). A systematic framework for defining R-squared measures in mediation analysis. Psychological Methods. Advance online publication. https://doi.org/10.1037/met0000571
Author
Shu Fai Cheung https://orcid.org/0000-0002-9871-9448
Examples
library(lavaan)
dat <- data_med
mod <-
"
m ~ x
y ~ m + x
"
fit <- sem(mod, dat)
dm <- delta_med(x = "x",
y = "y",
m = "m",
fit = fit)
dm
#> Call:
#> delta_med(x = "x", y = "y", m = "m", fit = fit)
#>
#> Predictor (x) : x
#> Mediator(s) (m) : m
#> Outcome variable (y): y
#>
#> Delta_med: 0.230
#>
#> Paths removed:
#> m~x
print(dm, full = TRUE)
#> Call:
#> delta_med(x = "x", y = "y", m = "m", fit = fit)
#>
#> Predictor (x) : x
#> Mediator(s) (m) : m
#> Outcome variable (y): y
#>
#> Delta_med: 0.230
#>
#> Paths removed:
#> m~x
#>
#> Additional information:
#> R-sq: Original : 0.351
#> R-sq: Mediator(s) removed : 0.121
#> Variance of y : 6.273
#> Variance of predicted y : 2.203
#> Variance of predicted: mediator(s) removed: 0.759
coef(dm)
#> [1] 0.2302121