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Module Biocaml_roc (.ml)

Performance measurement for binary classification.

This module provides functions to compute various performance measurement for binary classification. Typically, binary classifiers output both a label and a score indicating a confidence level. A ROC curve represents the variation of sensitivity and specificity of the classifier as a function of a score threshold.

module Biocaml_roc:
sig
type confusion_matrix = private {
   tp : int;
   tn : int;
   fp : int;
   fn : int;
} 
val make : pos:float Stream.t ->
       neg:float Stream.t -> (float * confusion_matrix) Stream.t
Given an enum pos (resp. neg) of scores from positive (resp. negative) instances, make ~pos ~neg builds an enum of confusion matrices by setting an decreasing acceptance threshold. The result has at least one first value, which is the confusion matrix for an infinity threshold. The subsequent thresholds are the values in pos and neg.
val sensitivity : confusion_matrix -> float
val false_positive_rate : confusion_matrix -> float
val accuracy : confusion_matrix -> float
val specificity : confusion_matrix -> float
val positive_predictive_value : confusion_matrix -> float
val negative_predictive_value : confusion_matrix -> float
val false_discovery_rate : confusion_matrix -> float
val f1_score : confusion_matrix -> float
val auc : (float * float) Stream.t -> float
auc e computes the area above the X-axis and under the piecewise linear curve passing through the points in e. Assumes that the points come with increasing x-coordinate.
end