sens defines a decision's sensitivity (or hit rate) value: The conditional probability of the decision being positive if the condition is TRUE.

sens

## Format

An object of class numeric of length 1.

## Details

Understanding or obtaining the sensitivity sens (or hit rate HR):

• Definition: sens is the conditional probability for a (correct) positive decision given that the condition is TRUE:

sens = p(decision = positive | condition = TRUE)

or the probability of correctly detecting true cases (condition = TRUE).

• Perspective: sens further classifies the subset of cond_true individuals by decision (sens = hi/cond_true).

• Alternative names: true positive rate (TPR), hit rate (HR), probability of detection, power = 1 - beta, recall

• Relationships:

a. sens is the complement of the miss rate mirt (aka. false negative rate FNR or the rate of Type-II errors):

sens = (1 - miss rate) = (1 - FNR)

b. sens is the opposite conditional probability -- but not the complement -- of the positive predictive value PPV:

PPV = p(condition = TRUE | decision = positive)

• In terms of frequencies, sens is the ratio of hi divided by cond_true (i.e., hi + mi):

sens = hi/cond_true = hi/(hi + mi)

• Dependencies: sens is a feature of a decision process or diagnostic procedure and a measure of correct decisions (true positives).

Due to being a conditional probability, the value of sens is not intrinsic to the decision process, but also depends on the condition's prevalence value prev.

## References

comp_sens computes sens as the complement of mirt; prob contains current probability information; comp_prob computes current probability information; num contains basic numeric parameters; init_num initializes basic numeric parameters; comp_freq computes current frequency information; is_prob verifies probabilities.
Other probabilities: FDR, FOR, NPV, PPV, acc, err, fart, mirt, ppod, prev, spec
Other essential parameters: cr, fa, hi, mi, prev, spec
sens <- .85     # sets a sensitivity value of 85%
is_prob(sens)   # TRUE#> [1] TRUE