match_FP_and_FN_counts_to_smaller_of_the_two: Match FP and FN counts to smaller of the two

In langfob/bdpg: Package For Building and Testing Biodiversity Problem Generators

Match FP and FN counts to smaller of the two

Description

Usually, the number of TNs and TPs will be unbalanced (i.e., there will usually be far more absences (TNs) than presences (TPs). Therefore, there will be far more opportunities to inject FPs than FNs or vice versa. Consequently, even if the FP and FN rates are set to the same value, there are likely to be far more FPs than FNs or vice versa in the apparent matrix. In many ecological cases, this would yield an unreasonable number of False Positives since False Positives are generally much less likely than False Negatives in field studies.

Usage

match_FP_and_FN_counts_to_smaller_of_the_two(
  num_TPs,
  num_TNs,
  FP_const_rate,
  FN_const_rate
)

Arguments

num_TPs	integer
num_TNs	integer
FP_const_rate	numeric
FN_const_rate	numeric

Details

So, this routine will adjust the error rate of the dominant value to yield the same _count_ as the other, e.g., if TNs are dominant, then the adjusted_P(FP) = num_FNs / num_TNs

Value

Returns FP_FN_const_rate_pair list

langfob/bdpg documentation built on Dec. 8, 2022, 5:33 a.m.