Incremental validity is the incremental accuracy in deciding whether or not a predictor will lead to an applicant being considered for the job. How important this factor is, depends on:
- Base rate: the rate of employees who are doing well at work without using the proposed predictor. Best incremental validity is associated with a moderate base rate.
- Selection ratio: the rate of people selected for a job to total applicants. Low selection rate is better since that means more applications and less hirings. The predictor score can be raised to decrease false positives.
The Taylor-Russell Tables are used to estimate the future employees who will be successful on the job if a selection method is used to hire them.