The research article you linked confirmed that job experience (years in a similar job) has positive predictive validity for job performance. Can a hiring manager improve their hiring decision by excluding a factor known to have positive predictive validity?
Interestingly, the study also says:
> work sample tests are the most costly of the three (although likely the best approach when hiring for positions that need specialized skills)
This roughly matches how a lot of hiring is done in practice, with the exception of evaluating candidates based on general intelligence. Unfortunately, candidates do not tend to take intelligence tests ahead of time to include in their resumes (nor would they be likely to as part of a specific interview), so this is not a suggestion that's easy to apply to typical hiring. Instead, hiring managers rely on years of experience, work sample tests, personal interests, and years of education, all which this study reports have positive predictive validity.
What concrete change should a manager of a small business make tomorrow to improve their hiring?
> The research article you linked confirmed that job experience (years in a similar job) has positive predictive validity for job performance.
Job performance does improve with experience up to a point (evidently six months), so this factor will have some predictive validity just for that, but this does not support comparing five years vs ten years.
> Can a hiring manager improve their hiring decision by excluding a factor known to have positive predictive validity?
Yes, if the manager had given undue weight to that factor (say, by rejecting applicants with little experience, regardless of performance on job knowledge tests), which is precisely what happens whenever managers consider employment history.
> This roughly matches how a lot of hiring is done in practice
No, what happens in practice is that managers say "no unemployed need apply" or ask for the applicant's "most recent résumé" (with dates, of course) and then exercise the sort of prejudice against the unemployed that you displayed earlier.
> What concrete change should a manager of a small business make tomorrow to improve their hiring?
The manager should filter applicants using GMA tests, job knowledge tests and integrity tests, which are inexpensive and have high validity, and then pay the candidates to take work-sample tests. The manager may consider experience (up to six months), but as no more than 5% of each candidate's grade, and this should be monitored by the business owner.
Interestingly, the study also says:
> work sample tests are the most costly of the three (although likely the best approach when hiring for positions that need specialized skills)
This roughly matches how a lot of hiring is done in practice, with the exception of evaluating candidates based on general intelligence. Unfortunately, candidates do not tend to take intelligence tests ahead of time to include in their resumes (nor would they be likely to as part of a specific interview), so this is not a suggestion that's easy to apply to typical hiring. Instead, hiring managers rely on years of experience, work sample tests, personal interests, and years of education, all which this study reports have positive predictive validity.
What concrete change should a manager of a small business make tomorrow to improve their hiring?