mpcs#

empulse.metrics.mpcs(y_true, y_score, *, loan_lost_rate=0.275, roi=0.2644, check_input=True)[source]#

Maximum Profit measure for Credit Scoring.

MPCS presumes a situation where a company is considering whether to grant a loan to a customer. Correctly identifying defaulters results in receiving a return on investment (ROI), while incorrectly identifying non-defaulters as defaulters results in a fraction of the loan amount being lost. For detailed information, consult the paper [1].

See also

mpcs_score : to only return the MPCS score.

empcs : for a stochastic version of this metric.

Parameters:
y_true1D array-like, shape=(n_samples,)

Binary target values (‘acquisition’: 1, ‘no acquisition’: 0).

y_score1D array-like, shape=(n_samples,)

Target scores, can either be probability estimates or non-thresholded decision values.

loan_lost_ratefloat, default=0.275

The fraction of the loan amount which is lost after default (loan_lost_rate 0).

roifloat, default=0.2644

Return on investment on the loan (roi 0).

check_inputbool, default=True

Perform input validation. Turning off improves performance, useful when using this metric as a loss function.

Returns:
mpcsfloat

Maximum Profit measure for Credit Scoring

thresholdfloat

Fraction of loan applications that should be accepted to maximize profit

Notes

The MP measure for Credit Scoring is defined as [1]:

\[\max_t \lambda \pi_0 F_0(t) - ROI \pi_1 F_1(t)\]

The MP measure for Credit Scoring requires that the default class is encoded as 0, and it is NOT interchangeable. However, this implementation assumes the standard notation (‘default’: 1, ‘no default’: 0).

References

[1] (1,2)

Verbraken, T., Bravo, C., Weber, R., & Baesens, B. (2014). Development and application of consumer credit scoring models using profit-based classification measures. European Journal of Operational Research, 238(2), 505-513.

Examples

>>> from empulse.metrics import mpcs
>>>
>>> y_true = [0, 1, 0, 1, 0, 1, 0, 1]
>>> y_score = [0.1, 0.2, 0.3, 0.4, 0.5, 0.7, 0.8, 0.9]
>>> mpcs(y_true, y_score)
(0.038349999999999995, 0.875)