cond_false {riskyr} | R Documentation |
Number of individuals for which the condition is false.
Description
cond_false
is a frequency that describes the
number of individuals in the current population N
for which the condition is FALSE
(i.e., actually false cases).
Usage
cond_false
Format
An object of class numeric
of length 1.
Details
Key relationships:
to probabilities: The frequency of
cond_false
individuals depends on the population sizeN
and the complement of the condition's prevalence1 - prev
and is split further into two subsets offa
by the false alarm ratefart
andcr
by the specificityspec
.Perspectives:
by condition:
The frequency
cond_false
is determined by the population sizeN
times the complement of the prevalence(1 - prev)
:cond_false= N x (1 - prev)
by decision:
a. The frequency
fa
is determined bycond_false
times the false alarm ratefart = (1 - spec)
(aka.FPR
):fa = cond_false x fart = cond_false x (1 - spec)
b. The frequency
cr
is determined bycond_false
times the specificityspec = (1 - fart)
:cr = cond_false x spec = cond_false x (1 - fart)
to other frequencies: In a population of size
N
the following relationships hold:
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_true
,
cr
,
dec_cor
,
dec_err
,
dec_neg
,
dec_pos
,
fa
,
hi
,
mi
Examples
cond_false <- 1000 * .90 # => sets cond_false to 90% of 1000 = 900 cases.
is_freq(cond_false) # => TRUE
is_prob(cond_false) # => FALSE, as cond_false is no probability [but (1 - prev) and spec are]