simstandard
Sometimes you have a structural model with standardized path
coefficients, structural coefficients, and correlations, but you do not
know the error and disturbance variances. The purpose of simstandard
is to calculate these variances and then simulate multivariate normal
data based on your model.
Installation
You can either install simstandard from CRAN or install the development version of simstandard from github.
Option 1: Install the most recent stable release from CRAN
You can install simstandard from CRAN by running this code:
install.packages("simstandard")Option 2: Install the development version from GitHub
To install the development version of simstandard, you need to check if devtools is installed. If not, run this:
install.packages("devtools")Once you are sure you have devtools installed, you can install the development version of simstandard from GitHub by running this code:
devtools::install_github("wjschne/simstandard")Example
The simstandard package uses lavaan
syntax to specify models.
library(simstandard)
model <- "
A =~ 0.5 * A1 + 0.8 * A2
B =~ 0.6 * B1 + 0.7 * B2
B ~ 0.8 * A
C ~~ 0.5 * A
"
data <- sim_standardized(m = model, n = 500)
knitr::kable(head(data), digits = 2)| A1 | A2 | B1 | B2 | C | A | B | e_A1 | e_A2 | e_B1 | e_B2 | d_B |
|---|---|---|---|---|---|---|---|---|---|---|---|
| -1.22 | 0.58 | 1.08 | 1.43 | 0.48 | -0.49 | 0.12 | -0.97 | 0.97 | 1.00 | 1.35 | 0.51 |
| -0.53 | 0.52 | 0.66 | 0.40 | -0.76 | 1.77 | 0.41 | -1.41 | -0.90 | 0.41 | 0.11 | -1.00 |
| -0.08 | 0.35 | 1.21 | 2.25 | 0.27 | 0.44 | 0.65 | -0.30 | 0.00 | 0.82 | 1.80 | 0.30 |
| 1.23 | 0.06 | -2.34 | -1.45 | 0.16 | 0.39 | -0.63 | 1.04 | -0.26 | -1.96 | -1.00 | -0.95 |
| -0.38 | -0.86 | -0.66 | -2.23 | -0.96 | -1.69 | -1.48 | 0.47 | 0.50 | 0.23 | -1.19 | -0.12 |
| 0.63 | 0.55 | -0.65 | -0.56 | -0.02 | 0.22 | -0.12 | 0.51 | 0.38 | -0.58 | -0.47 | -0.30 |
See more in the tutorial for this package.