Skip to contents

Function for fitting random-effects, meta-regression, multilevel, and location-scale meta-analytic selection models.

Usage

bselmodel(
  yi,
  vi,
  sei,
  weights,
  ni,
  mods,
  scale,
  cluster,
  data,
  slab,
  subset,
  measure,
  prior_effect,
  prior_heterogeneity,
  prior_mods,
  prior_scale,
  prior_heterogeneity_allocation,
  prior_bias,
  standardize_continuous_predictors = TRUE,
  set_contrast_factor_predictors = "treatment",
  prior_unit_information_sd,
  rescale_priors = 1,
  prior_informed_field,
  prior_informed_subfield,
  effect_direction = "detect",
  steps,
  sample = 5000,
  burnin = 2000,
  adapt = 500,
  chains = 3,
  thin = 1,
  parallel = FALSE,
  autofit = FALSE,
  autofit_control = set_autofit_control(),
  convergence_checks = set_convergence_checks(),
  seed = NULL,
  silent,
  ...
)

Arguments

yi

a vector of effect sizes, or a formula with the effect size on the left-hand side and location moderators on the right-hand side (for example yi ~ x1 + x2). If a formula is supplied, mods must not be specified.

vi

a vector of sampling variances. Either vi or sei must be supplied for normal models.

sei

a vector of standard errors. Either vi or sei must be supplied for normal models.

weights

an optional vector of positive likelihood weights. For normal/effect-size models, each weight powers the estimate likelihood. For constructors with GLMM raw-count input, each weight powers the paired two-arm likelihood for one study.

ni

an optional vector of sample sizes. Used for measure = "GEN" or when estimating "UISD").

mods

an optional matrix, data.frame, or formula specifying location moderators (meta-regressors). Formula input is evaluated in data.

scale

an optional matrix, data.frame, or formula specifying scale predictors for location-scale models. Formula input is evaluated in data.

cluster

an optional vector of cluster identifiers for multilevel meta-analysis.

data

an optional data frame containing the variables.

slab

an optional vector of study labels.

subset

an optional logical or numeric vector specifying a subset of data to be used.

measure

a character string specifying the effect size measure. Normal/effect-size constructors require an explicit value and support "SMD", "ZCOR", "RR", "OR", "HR", "RD", "IRR", and "GEN". Use "GEN" only for general effect sizes without a known unit information standard deviation. GLMM raw-count constructors support only "OR" and "IRR" and default to "OR".

prior_effect

prior distribution for the effect size (\(\mu\)) parameter (the intercept). If omitted, a default prior is constructed. In single-model functions, explicit NULL or FALSE sets a spike at zero.

prior_heterogeneity

prior distribution for the heterogeneity (\(\tau\)) parameter. If omitted, a default prior is constructed. In single-model functions, explicit NULL or FALSE sets a spike at zero.

prior_mods

prior distribution for the moderators (\(\beta\)) parameters. A single prior applies to all terms; a named list can specify term-specific priors. If omitted or NULL, default priors are used.

prior_scale

prior distribution for the scale (\(\delta\)) parameters. A single prior applies to all terms; a named list can specify term-specific priors. If omitted or NULL, default priors are used.

prior_heterogeneity_allocation

prior distribution for the fraction of heterogeneity allocated to the cluster-level component in multilevel models (\(\rho\)). If omitted or NULL, defaults to Beta(1, 1).

prior_bias

selection-model bias prior, usually created by prior_weightfunction(). If omitted or NULL, a default one-sided weightfunction prior is constructed from steps.

standardize_continuous_predictors

logical. Whether to standardize continuous predictors. Defaults to TRUE.

set_contrast_factor_predictors

character. How to set contrast for factor predictors. Defaults are constructor-specific and shown in each function usage; single-model constructors use "treatment", while model-averaging constructors use "meandif".

prior_unit_information_sd

numeric. The unit information standard deviation (\(\sigma_{unit}\)). Cannot be used together with prior_informed_field.

rescale_priors

numeric. A scaling factor for supported prior distributions. Point and none priors are unchanged. For constructors with publication-bias prior distributions, rescale_priors does not rescale them except for the default PEESE prior's UISD adjustment. Defaults to 1.

prior_informed_field

character. The field of the informed prior distributions. Omit to use the standard default prior specification; explicit NULL is invalid.

prior_informed_subfield

character. The subfield of the informed prior distributions. Omit to use the field-specific default, such as "Cochrane" for prior_informed_field = "medicine"; explicit NULL is invalid.

effect_direction

direction used by publication-bias adjustments. "positive" assumes statistically significant positive estimates are more likely to be selected; "negative" mirrors the selection direction; "detect" infers the direction from the fitted data.

steps

numeric vector of one-sided p-value cut points for the default selection model. If prior_bias is supplied, the prior carries its own side, steps, and weights. If omitted, the default is 0.025, yielding intervals [0, .025] and (.025, 1].

sample

numeric. Number of MCMC samples to save. Defaults to 5000.

burnin

numeric. Number of burn-in iterations. Defaults to 2000.

adapt

numeric. Number of adaptation iterations. Defaults to 500.

chains

numeric. Number of MCMC chains. Defaults to 3.

thin

numeric. Thinning interval. Defaults to 1.

parallel

logical. Whether to run MCMC chains in parallel. Defaults to FALSE.

autofit

logical. Whether to automatically extend the MCMC chains if convergence is not met. Defaults to FALSE.

autofit_control

list of autofit control settings. See set_autofit_control() for details.

convergence_checks

list of convergence check settings. See set_convergence_checks() for details.

seed

numeric. Random seed for reproducibility. Defaults to NULL.

silent

logical. Whether to suppress output. Constructors with no explicit default use RoBMA.get_option("silent") when silent is omitted. Model-averaging wrappers default to TRUE unless explicitly changed.

...

additional advanced arguments. Fitting functions reject unused arguments; currently recognized internal arguments include only_data, only_priors, is_JASP, and is_JASP_prefix.

Value

A fitted object of class c("bselmodel", "brma") containing a single Bayesian selection model fit.

Details

bselmodel() is a normal/effect-size selection-model constructor. Custom prior_bias can be a weightfunction prior or a supported BayesTools selection-kernel prior; p-hacking kernels are not supported in active RoBMA.

Examples

if (FALSE) { # \dontrun{
if (requireNamespace("metadat", quietly = TRUE)) {
  data(dat.lehmann2018, package = "metadat")

  fit <- bselmodel(
    yi      = yi,
    vi      = vi,
    data    = dat.lehmann2018,
    measure = "SMD",
    steps   = 0.025,
    seed    = 1,
    silent  = TRUE
  )

  summary(fit)
  funnel(fit)
}
} # }