acc
: Overall accuracy as the proportion (or probability)
of correctly classifying cases or of dec.cor
cases:
acc = dec.cor/N = (hi + cr)/(hi + mi + fa + cr)
Values range from 0 (no correct prediction) to 1 (perfect prediction).
wacc
: Weighted accuracy, as a weighted average of the
sensitivity sens
(aka. hit rate HR
, TPR
,
power
or recall
)
and the the specificity spec
(aka. TNR
)
in which sens
is multiplied by a weighting parameter w
(ranging from 0 to 1) and spec
is multiplied by
w
's complement (1 - w)
:
wacc = (w * sens) + ((1 - w) * spec)
If w = .50
, wacc
becomes balanced accuracy bacc
.
mcc
: The Matthews correlation coefficient (with values ranging from -1 to +1):
mcc = ((hi * cr) - (fa * mi)) / sqrt((hi + fa) * (hi + mi) * (cr + fa) * (cr + mi))
A value of mcc = 0
implies random performance; mcc = 1
implies perfect performance.
See Wikipedia: Matthews correlation coefficient
for additional information.
f1s
: The harmonic mean of the positive predictive value PPV
(aka. precision
)
and the sensitivity sens
(aka. hit rate HR
,
TPR
, power
or recall
):
f1s = 2 * (PPV * sens) / (PPV + sens)
See Wikipedia: F1 score for additional information.