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Produces APA-style narrative text interpreting the results of a differential- functioning analysis or interaction table. For method = "refit", the report summarises the number of facet levels classified as negligible (A), moderate (B), and large (C). For method = "residual", it summarises screening-positive results, lists the specific levels and their direction, and includes a caveat about the distinction between construct-relevant variation and measurement bias.

Usage

dif_report(dif_result, ...)

Arguments

dif_result

Output from analyze_dff() / analyze_dif() (class mfrm_dff with compatibility class mfrm_dif) or dif_interaction_table() (class mfrm_dif_interaction).

...

Currently unused; reserved for future extensions.

Value

Object of class mfrm_dif_report with narrative, counts, large_dif, and config.

Details

When dif_result is an mfrm_dff/mfrm_dif object, the report is based on the pairwise differential-functioning contrasts in $dif_table. When it is an mfrm_dif_interaction object, the report uses the cell-level statistics and flags from $table.

For method = "refit", ETS-style magnitude labels are used only when subgroup calibrations were successfully linked back to a common baseline scale; otherwise the report labels those contrasts as unclassified because the refit difference is descriptive rather than comparable on a linked logit scale. For method = "residual", the report describes screening-positive versus screening-negative contrasts instead of applying ETS labels.

Interpreting output

  • $narrative: character scalar with the full narrative text.

  • $counts: named integer vector of method-appropriate counts.

  • $large_dif: tibble of large ETS results (method = "refit") or screening-positive contrasts/cells (method = "residual").

  • $config: analysis configuration inherited from the input.

Typical workflow

  1. Run analyze_dff() / analyze_dif() or dif_interaction_table().

  2. Pass the result to dif_report().

  3. Print the report or extract $narrative for inclusion in a manuscript.

Examples

toy <- load_mfrmr_data("example_bias")

fit <- fit_mfrm(toy, "Person", c("Rater", "Criterion"), "Score",
                 method = "JML", model = "RSM", maxit = 25)
diag <- diagnose_mfrm(fit, residual_pca = "none")
dif <- analyze_dff(fit, diag, facet = "Rater", group = "Group", data = toy)
rpt <- dif_report(dif)
cat(rpt$narrative)
#> DRF screening was conducted for the Rater facet across levels of Group using the residual method. A total of 4 pairwise facet-level comparisons were evaluated. 0 comparison(s) were screening-positive and 4 were screening-negative based on the residual-contrast test. 
#> No pairwise contrasts were screening-positive under the residual-screening method. This does not by itself establish invariance or consistent functioning across groups. 
#> Note: The presence of differential functioning does not necessarily indicate measurement bias. Differential functioning may reflect construct-relevant variation (e.g., true group differences in the attribute being measured) rather than unwanted measurement bias. Substantive review is recommended to distinguish between these possibilities (cf. Eckes, 2011; McNamara & Knoch, 2012).