Tidy summarizes information about the components of a model. A model component might be a single term in a regression, a single hypothesis, a cluster, or a class. Exactly what tidy considers to be a model component varies across models but is usually self-evident. If a model has several distinct types of components, you will need to specify which components to return.
The methods should work with any model that conforms to the ergm class, such as those produced from weighted networks by the ergm.count package.
Usage
# S3 method for class 'ergm'
tidy(x, conf.int = FALSE, conf.level = 0.95, exponentiate = FALSE, ...)Arguments
- x
An
ergmobject returned from a call toergm::ergm().- conf.int
Logical indicating whether or not to include a confidence interval in the tidied output. Defaults to
FALSE.- conf.level
The confidence level to use for the confidence interval if
conf.int = TRUE. Must be strictly greater than 0 and less than 1. Defaults to 0.95, which corresponds to a 95 percent confidence interval.- exponentiate
Logical indicating whether or not to exponentiate the the coefficient estimates. This is typical for logistic and multinomial regressions, but a bad idea if there is no log or logit link. Defaults to
FALSE.- ...
Additional arguments to pass to
ergm::summary(). Cautionary note: Misspecified arguments may be silently ignored.
Value
A tibble::tibble with one row for each coefficient in the exponential random graph model, with columns:
- term
The term in the model being estimated and tested
- estimate
The estimated coefficient
- std.error
The standard error
- mcmc.error
The MCMC error
- p.value
The two-sided p-value
References
Hunter DR, Handcock MS, Butts CT, Goodreau SM, Morris M (2008b). ergm: A Package to Fit, Simulate and Diagnose Exponential-Family Models for Networks. Journal of Statistical Software, 24(3). https://www.jstatsoft.org/v24/i03/.
See also
tidy(), ergm::ergm(), ergm::control.ergm(),
ergm::summary()
Other ergm tidiers:
glance.ergm()
Examples
# load libraries for models and data
library(ergm)
#>
#> ‘ergm’ 4.6.0 (2023-12-17), part of the Statnet Project
#> * ‘news(package="ergm")’ for changes since last version
#> * ‘citation("ergm")’ for citation information
#> * ‘https://statnet.org’ for help, support, and other information
#> ‘ergm’ 4 is a major update that introduces some
#> backwards-incompatible changes. Please type
#> ‘news(package="ergm")’ for a list of major changes.
#>
#> Attaching package: ‘ergm’
#> The following object is masked from ‘package:btergm’:
#>
#> gof
# load the Florentine marriage network data
data(florentine)
# fit a model where the propensity to form ties between
# families depends on the absolute difference in wealth
gest <- ergm(flomarriage ~ edges + absdiff("wealth"))
#> Starting maximum pseudolikelihood estimation (MPLE):
#> Obtaining the responsible dyads.
#> Evaluating the predictor and response matrix.
#> Maximizing the pseudolikelihood.
#> Finished MPLE.
#> Evaluating log-likelihood at the estimate.
#>
# show terms, coefficient estimates and errors
tidy(gest)
#> # A tibble: 2 × 6
#> term estimate std.error mcmc.error statistic p.value
#> <chr> <dbl> <dbl> <dbl> <dbl> <dbl>
#> 1 edges -2.30 0.402 0 -5.73 0.0000000102
#> 2 absdiff.wealth 0.0155 0.00616 0 2.52 0.0117
# show coefficients as odds ratios with a 99% CI
tidy(gest, exponentiate = TRUE, conf.int = TRUE, conf.level = 0.99)
#> Warning: Exponentiating but model didn't use log or logit link.
#> # A tibble: 2 × 8
#> term estimate std.error mcmc.error statistic p.value conf.low conf.high
#> <chr> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
#> 1 edges 0.100 0.402 0 -5.73 1.02e-8 0.0355 0.282
#> 2 absd… 1.02 0.00616 0 2.52 1.17e-2 1.00 1.03
# take a look at likelihood measures and other
# control parameters used during MCMC estimation
glance(gest)
#> # A tibble: 1 × 5
#> independence iterations logLik AIC BIC
#> <lgl> <int> <dbl> <dbl> <dbl>
#> 1 TRUE 4 -51.0 106. 112.
glance(gest, deviance = TRUE)
#> # A tibble: 1 × 9
#> independence iterations logLik null.deviance df.null residual.deviance
#> <lgl> <int> <dbl> <logLik> <int> <dbl>
#> 1 TRUE 4 -51.0 166.3553 120 102.
#> # ℹ 3 more variables: df.residual <int>, AIC <dbl>, BIC <dbl>
glance(gest, mcmc = TRUE)
#> Though `glance` was supplied `mcmc = TRUE`, the model was not fittedusing MCMC, so the corresponding columns will be omitted.
#> # A tibble: 1 × 5
#> independence iterations logLik AIC BIC
#> <lgl> <int> <dbl> <dbl> <dbl>
#> 1 TRUE 4 -51.0 106. 112.