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The paired-comparison counterpart of the kidmap. A judge has no ability to condition on, so the reference is the consensus object scale (the pooled locations). For the nominated judge, each object it met is given a standardised residual oriented to the object – how much more (z > 0, over-rated) or less (z < 0, under-rated) that judge favoured it than its consensus location predicts. Approximate two-sided normal probabilities are adjusted by Holm across the objects meeting min_n. A surprise is an eligible object treated against its standing (residual opposite in sign to the location) whose adjusted probability passes the level represented by flag_z. The fitted model must have converged. An adequately sampled object with unavailable residual inference remains in the adjustment family.

Usage

judge_surprise(fit, judge, min_n = 2L, flag_z = 1.96)

Arguments

fit

A paired-comparison fit from btl with judges.

judge

The judge to profile (a value of the fit's judge column).

min_n

Objects met fewer times are shown but never flagged.

flag_z

Absolute normal-residual threshold defining the familywise flagging level; 1.96 corresponds to an adjusted two-sided probability of approximately 0.05.

Value

A list of class "rasch_btl_judge": objects (per object met: location, times met n, residual z, approximate p, Holm-adjusted p_adj, surprise flag and its type). Strong and weak refer to standing above or below the mean calibrated-object location, so the classification is unchanged by the arbitrary scale origin. all_locations contains every object for orientation; the judge and settings.

Examples

set.seed(1); objs <- LETTERS[1:6]; beta <- setNames(seq(-1.5, 1.5, len = 6), objs)
pr <- t(utils::combn(objs, 2))
d <- data.frame(a = rep(pr[, 1], each = 12), b = rep(pr[, 2], each = 12))
d$judge <- sample(paste0("J", 1:5), nrow(d), TRUE)
d$win <- ifelse(runif(nrow(d)) < plogis(beta[d$a] - beta[d$b]), d$a, d$b)
judge_surprise(btl(d, "a", "b", "win", judge = "judge"), "J1")
#> Judge J1: 40 comparisons over 6 objects
#> No object judged against its consensus standing.