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Estimates the variance of d' (and criterion) from summary SDT counts using the Gourevitch & Galanter (1967) delta method, the Miller (1996) exact-binomial method, or a parametric bootstrap.

Usage

sdt_summary_variance(
  hits,
  fas,
  misses,
  cr,
  method = c("miller", "gourevitch", "bootstrap"),
  correction = c("loglinear", "half", "none"),
  nboot = 1000,
  seed = NULL
)

Arguments

hits

Number of hits.

fas

Number of false alarms.

misses

Number of misses.

cr

Number of correct rejections.

method

Variance method: "gourevitch", "miller", or "bootstrap".

correction

Correction for extreme rates ("loglinear", "half", or "none").

nboot

Number of bootstrap samples when method = "bootstrap".

seed

Optional random seed for bootstrap variance.

Value

A list with variance estimates for zH, zF, d', and c.

Details

Miller enumeration is exact for a binomial distribution at its supplied probability. Here that probability is estimated from the observed counts. The resulting variance and downstream Wald test are plug-in approximations, not exact finite-sample inference.

Examples

v <- sdt_summary_variance(hits = 70, fas = 20, misses = 30, cr = 80,
                          method = "miller")
v$var_dprime
#> [1] 0.03758609