denominator_diagnostics: Denominator diagnostics for an LTG-SMD analysis

In ltgsmd: Latent True-Score and Target-Population Anchored Geometric SMD

Denominator diagnostics for an LTG-SMD analysis

Description

Produces the diagnostic table recommended in Section 8.3 of the companion paper (Table F.1 format). The table reports group-level sample sizes, observed standard deviations, reference reliabilities, true-score standard deviations, study-to-reference ratios c_g, Hedges's g, the LTG-SMD, the reliability factor (\rho_1 \rho_0)^{1/4}, the study-to-target factor (c_1 c_0)^{-1/2}, the predicted ratio of the within-study observed geometric SMD to the LTG-SMD (exact under the decomposition), and the observed ratio of Hedges's g to the LTG-SMD (which approximately matches the predicted ratio with small deviations due to the pooled-versus-geometric denominator and Hedges's J correction).

Usage

denominator_diagnostics(x)

Arguments

x	An "ltg_smd" object.

Value

A data frame in a long format suitable for direct reporting. The data frame has class "denominator_diagnostics".

Examples

set.seed(2026)
gen_items <- function(n, shift = 0) {
  true <- rnorm(n)
  data.frame(
    item1 = true + rnorm(n, sd = 0.6) + shift,
    item2 = true + rnorm(n, sd = 0.6) + shift,
    item3 = true + rnorm(n, sd = 0.6) + shift,
    item4 = true + rnorm(n, sd = 0.6) + shift
  )
}
study_df <- rbind(
  cbind(condition = "control",   gen_items(15)),
  cbind(condition = "treatment", gen_items(15, shift = 0.5))
)
reference_df <- rbind(
  cbind(condition = "control",   gen_items(30)),
  cbind(condition = "treatment", gen_items(30, shift = 0.5))
)
result <- compute_ltg_smd(study_df, reference_df,
  group_var = "condition", items = c("item1", "item2", "item3", "item4"),
  group_levels = c(reference = "control", focal = "treatment"))
diag <- denominator_diagnostics(result)
print(diag)

ltgsmd documentation built on Sept. 27, 2026, 5:07 p.m.