dec.neg: Number of individuals for which the decision is negative.

Description Usage Format Details References See Also Examples

Description

dec.neg is a frequency that describes the number of individuals in the current population N for which the decision is negative (i.e., cases not called or not predicted).

Usage

1

Format

An object of class numeric of length 1.

Details

Key relationships:

  1. to probabilities: The frequency of dec.neg individuals depends on the population size N and the decision's proportion of negative decisions (1 - ppod) and is split further into two subsets of cr by the negative predictive value NPV and mi by the false omission rate FOR = 1 - NPV.

    Perspectives:

    1. by condition:

      The frequency dec.neg is determined by the population size N times the proportion of negative decisions (1 - ppod):

      dec.neg = N x (1 - ppod)

    2. by decision:

      a. The frequency cr is determined by dec.neg times the negative predictive value NPV:

      cr = dec.neg x NPV

      b. The frequency mi is determined by dec.neg times the false omission rate FOR = (1 - NPV):

      mi = dec.neg x FOR = dec.neg x (1 - NPV)

  2. to other frequencies: In a population of size N the following relationships hold:

    • N = cond.true + cond.false (by condition)

    • N = dec.pos + dec.neg (by decision)

    • N = dec.cor + dec.err (by correspondence of decision to condition)

    • N = hi + mi + fa + cr (by condition x decision)

Current frequency information is computed by comp_freq and contained in a list freq.

References

Consult Wikipedia: Confusion matrix for additional information.

See Also

is_freq verifies frequencies; num contains basic numeric parameters; init_num initializes basic numeric parameters; freq contains current frequency information; comp_freq computes current frequency information; prob contains current probability information; comp_prob computes current probability information.

Other frequencies: N, cond.false, cond.true, cr, dec.cor, dec.err, dec.pos, fa, hi, mi

Examples

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dec.neg <- 1000 * .67   # => sets dec.neg to 67% of 1000 = 670 cases.
is_freq(dec.neg)        # => TRUE
is_prob(dec.neg)        # => FALSE, as dec.neg is no probability (but ppod, NPV and FOR are)

riskyr documentation built on Feb. 19, 2018, 5 p.m.