dec_neg: Number of individuals for which the decision is negative.
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
dec_neg
Arguments
Format
An object of class numeric of length 1.
Details
Key relationships:
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:
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)
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)
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.
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
dec_neg <- 1000 * .67# => sets dec_neg to 67% of 1000 = 670 cases.is_freq(dec_neg) # => TRUEis_prob(dec_neg) # => FALSE, as dec_neg is no probability (but ppod, NPV and FOR are)