is_suff_prob_set: Verify a sufficient set of probability inputs.

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Verify a sufficient set of probability inputs.

Description

is_suff_prob_set is a function that takes 3 to 5 probabilities as inputs and verifies that they are sufficient to compute all derived probabilities and combined frequencies for a population of N individuals.

Usage

is_suff_prob_set(prev, sens = NA, mirt = NA, spec = NA, fart = NA)

Arguments

prev	The condition's prevalence prev (i.e., the probability of condition being TRUE).
sens	The decision's sensitivity sens (i.e., the conditional probability of a positive decision provided that the condition is TRUE). sens is optional when its complement mirt is provided.
mirt	The decision's miss rate mirt (i.e., the conditional probability of a negative decision provided that the condition is TRUE). mirt is optional when its complement sens is provided.
spec	The decision's specificity value spec (i.e., the conditional probability of a negative decision provided that the condition is FALSE). spec is optional when its complement fart is provided.
fart	The decision's false alarm rate fart (i.e., the conditional probability of a positive decision provided that the condition is FALSE). fart is optional when its complement spec is provided.

Details

While no alternative input option for frequencies is provided, specification of the essential probability prev is always necessary.

However, for 2 other essential probabilities there is a choice:

1. either sens or mirt is necessary (as both are complements).

2. either spec or fart is necessary (as both are complements).

is_suff_prob_set does not verify the type, range, or consistency of its arguments. See is_prob and is_complement for this purpose.

Value

A Boolean value: TRUE if the probabilities provided are sufficient, otherwise FALSE.

See Also

num contains basic numeric variables; init_num initializes basic numeric variables; prob contains current probability information; comp_prob computes current probability information; freq contains current frequency information; comp_freq computes current frequency information; is_valid_prob_set verifies the validity of probability inputs; as_pc displays a probability as a percentage; as_pb displays a percentage as probability.

Other verification functions: is_complement(), is_extreme_prob_set(), is_freq(), is_integer(), is_matrix(), is_perc(), is_prob(), is_valid_prob_pair(), is_valid_prob_set(), is_valid_prob_triple()

Examples

# ways to work:
is_suff_prob_set(prev = 1, sens = 1, spec = 1)  # => TRUE
is_suff_prob_set(prev = 1, mirt = 1, spec = 1)  # => TRUE
is_suff_prob_set(prev = 1, sens = 1, fart = 1)  # => TRUE
is_suff_prob_set(prev = 1, mirt = 1, fart = 1)  # => TRUE

# watch out for:
is_suff_prob_set(prev = 1, sens = 2, spec = 3)  # => TRUE, but is_prob is FALSE
is_suff_prob_set(prev = 1, mirt = 2, fart = 4)  # => TRUE, but is_prob is FALSE
is_suff_prob_set(prev = 1, sens = 2, spec = 3, fart = 4)  # => TRUE, but is_prob is FALSE

## ways to fail:
# is_suff_prob_set()                    # => FALSE + warning (prev missing)
# is_suff_prob_set(prev = 1)            # => FALSE + warning (sens or mirt missing)
# is_suff_prob_set(prev = 1, sens = 1)  # => FALSE + warning (spec or fart missing)

riskyr documentation built on Aug. 15, 2022, 9:09 a.m.