Get model parameters

Returns the coefficients (or posterior samples for Bayesian models) from a model.

get_parameters(x, ...)

# S3 method for betamfx
get_parameters(
  x,
  component = c("all", "conditional", "precision", "marginal"),
  ...
)

# S3 method for logitmfx
get_parameters(x, component = c("all", "conditional", "marginal"), ...)

# S3 method for emmGrid
get_parameters(x, summary = FALSE, merge_parameters = FALSE, ...)

# S3 method for averaging
get_parameters(x, component = c("conditional", "full"), ...)

# S3 method for betareg
get_parameters(x, component = c("all", "conditional", "precision"), ...)

# S3 method for DirichletRegModel
get_parameters(x, component = c("all", "conditional", "precision"), ...)

# S3 method for clm2
get_parameters(x, component = c("all", "conditional", "scale"), ...)

# S3 method for coxme
get_parameters(x, effects = c("fixed", "random"), ...)

# S3 method for merMod
get_parameters(x, effects = c("fixed", "random"), ...)

# S3 method for mixed
get_parameters(x, effects = c("fixed", "random"), ...)

# S3 method for glmmTMB
get_parameters(
  x,
  effects = c("fixed", "random"),
  component = c("all", "conditional", "zi", "zero_inflated", "dispersion"),
  ...
)

# S3 method for BBmm
get_parameters(x, effects = c("fixed", "random"), ...)

# S3 method for glimML
get_parameters(x, effects = c("fixed", "random", "all"), ...)

# S3 method for gam
get_parameters(x, component = c("all", "conditional", "smooth_terms"), ...)

# S3 method for zeroinfl
get_parameters(
  x,
  component = c("all", "conditional", "zi", "zero_inflated"),
  ...
)

# S3 method for zcpglm
get_parameters(
  x,
  component = c("all", "conditional", "zi", "zero_inflated"),
  ...
)

# S3 method for BGGM
get_parameters(
  x,
  component = c("correlation", "conditional", "intercept", "all"),
  summary = FALSE,
  ...
)

# S3 method for MCMCglmm
get_parameters(x, effects = c("fixed", "random", "all"), summary = FALSE, ...)

# S3 method for BFBayesFactor
get_parameters(
  x,
  effects = c("all", "fixed", "random"),
  component = c("all", "extra"),
  iterations = 4000,
  progress = FALSE,
  verbose = TRUE,
  ...
)

# S3 method for stanmvreg
get_parameters(
  x,
  effects = c("fixed", "random", "all"),
  parameters = NULL,
  summary = FALSE,
  ...
)

# S3 method for brmsfit
get_parameters(
  x,
  effects = c("fixed", "random", "all"),
  component = c("all", "conditional", "zi", "zero_inflated", "dispersion", "simplex",
    "sigma", "smooth_terms"),
  parameters = NULL,
  summary = FALSE,
  ...
)

# S3 method for stanreg
get_parameters(
  x,
  effects = c("fixed", "random", "all"),
  parameters = NULL,
  summary = FALSE,
  ...
)

# S3 method for sim.merMod
get_parameters(
  x,
  effects = c("fixed", "random", "all"),
  parameters = NULL,
  summary = FALSE,
  ...
)

Arguments

x	A fitted model.
...	Currently not used.
component	Should all parameters, parameters for the conditional model, the zero-inflated part of the model, the dispersion term, the instrumental variables or marginal effects be returned? Applies to models with zero-inflated and/or dispersion formula, or to models with instrumental variables (so called fixed-effects regressions), or models with marginal effects from mfx. May be abbreviated. Note that the conditional component is also called count or mean component, depending on the model.
summary	Logical, indicates whether the full posterior samples (summary = FALSE)) or the summarized centrality indices of the posterior samples (summary = TRUE)) should be returned as estimates.
merge_parameters	Logical, if TRUE and x has multiple columns for parameter names (like emmGrid objects may have), these are merged into a single parameter column, with parameters names and values as values.
effects	Should parameters for fixed effects, random effects or both be returned? Only applies to mixed models. May be abbreviated.
iterations	Number of posterior draws.
progress	Display progress.
verbose	Toggle messages and warnings.
parameters	Regular expression pattern that describes the parameters that should be returned.

Value

• for non-Bayesian models and if effects = "fixed", a data frame with two columns: the parameter names and the related point estimates

• if effects = "random", a list of data frames with the random effects (as returned by ranef()), unless the random effects have the same simplified structure as fixed effects (e.g. for models from MCMCglmm)

• for Bayesian models, the posterior samples from the requested parameters as data frame

• for Anova (aov()) with error term, a list of parameters for the conditional and the random effects parameters

• for models with smooth terms or zero-inflation component, a data frame with three columns: the parameter names, the related point estimates and the component

Details

In most cases when models either return different "effects" (fixed, random) or "components" (conditional, zero-inflated, ...), the arguments effects and component can be used.

get_parameters() is comparable to coef(), however, the coefficients are returned as data frame (with columns for names and point estimates of coefficients). For Bayesian models, the posterior samples of parameters are returned.

BFBayesFactor Models

Note that for BFBayesFactor models (from the BayesFactor package), posteriors are only extracted from the first numerator model (i.e., model[1]). If you want to apply some function foo() to another model stored in the BFBayesFactor object, index it directly, e.g. foo(model[2]), foo(1/model[5]), etc. See also weighted_posteriors.

Examples

data(mtcars)
m <- lm(mpg ~ wt + cyl + vs, data = mtcars)
get_parameters(m)
#>     Parameter   Estimate
#> 1 (Intercept) 38.7460642
#> 2          wt -3.2463673
#> 3         cyl -1.3641033
#> 4          vs  0.5241721