Classification threshold determination method and device and machine learning model evaluation method and device

The invention discloses a classification threshold determination and machine learning model evaluation method and device, and relates to the technical field of artificial intelligence. A specific embodiment of the classification threshold determination method comprises the steps of obtaining evaluation scores of a plurality of samples, dividing the samples into a plurality of sample sets according to the evaluation scores, and arranging the sample sets according to a preset sequence of the evaluation scores; counting an accumulated positive sample proportion and an accumulated negative sample proportion of each sample set; determining a positive sample rejection scale factor and a positive sample scale tuning item of the sample set according to the accumulated positive sample scale of each sample set; determining a negative sample distribution correction factor and a negative sample proportion tuning item of the sample set based on the evaluation score of each sample in each sample set; and according to the p