Implementing the curve itself should not be too difficult (probably with a discrete or modular backend),
but the area under the curve may be hard.
In a talk, Rob Holte mentioned that they convert the cost curve to a ROC curve and compute the area under that (these curves have line-point duality).
Implement cost curves in an evaluator, ala: https://link.springer.com/content/pdf/10.1007/s10994-006-8199-5.pdf
Implementing the curve itself should not be too difficult (probably with a discrete or modular backend), but the area under the curve may be hard. In a talk, Rob Holte mentioned that they convert the cost curve to a ROC curve and compute the area under that (these curves have line-point duality).