How many times in your career have you suffered through an interview for a position and been presented with exhausting questions such as “where do you see yourself in five years?” or “what is your greatest strength/weakness?” I recall an interview I had with a prestigious investment-banking firm and was asked “how many pencils to you think will fit into this office?” I’ve never been quite certain the purpose of that inquiry, perhaps it was to make the interviewer feel powerful or clever.
There is a significant scientific body of evidence to suggest that the basic job interview is an ineffective method to select the best candidate. Some of this is due to what is known widely as confirmation bias. Individuals, based largely on primitive instincts, assess our fellow humans quickly. When we all lived on the savannah this rapid assessment might make the difference between life and death. In modern society the impact is subtler. If we don’t like someone’s handshake, how he or she dresses, his or her appearance, etc the interview is basically over. The interviewer proceeds to continually look for reasons to reject you in order to confirm the basic impression.
This dangerous path is particularly true with unstructured interviews, which surprisingly remain commonplace. It unfolds like this- a candidate who appears reserved or maybe introverted might be asked if they are “comfortable in a large group setting”. A candidate for the same role who presents as outgoing, extroverted and confident might be asked is they have experience “leading large teams.” This is the confirmation bias at work.
Other factors that influence the hiring decision include height, attractiveness, and the sound of someone’s voice. There is also evidence to suggest that when a candidate is interviewed has an influence on hiring. Interviewer assess candidates not simply on the merits of their particular interview performance, but they also take into account the rating of candidates they have already interviewed. So if an interviewer has already awarded several high ratings they are less likely to award high ratings later in the interview cycle.
All of this evidence paints a dismal picture of the interviewing process. Luckily, science points to several variations on the classic interview that can increase the odds of selecting the ideal candidate. A meta analysis covering nearly a century of research uncovered some interesting findings on how effective various assessments are in predicting employee performance.*
The worst predictors of employee performance are-
- Work experience
- Reference checks
- Unstructured interviews
Combined these three assessment methods account for only 24% of an employee’s performance.
The top predictors of employee performance are_
- Work sample tests
- Structured interviews
These two assessment methods combined account for 55% of an employee’s performance.
Why don’t more employers use structured interviews? They are time consuming and hard to develop. But lets do some math. Lets say you and your team of 2 staff spend a collective 40 hours developing structured interview questions based on the competencies you are seeking in a new employee. At a total compensation rate of $200,000 per year, those 40 hours have cost $3,846. Let’s further assume you need to train 3 interview panel members, taking another collective 40 hours (your staff time and the time of the panel members) for an additional $3,846. This represents an incremental cost to your hiring process.
The alternative is sticking to a more traditional method and taking your chances. If you misjudge, the cost of sending your new hire to training will be significantly more expensive and if you count in the opportunity cost of having an employee in training, the possibility of HR time intervening and working with the manager (developing performance improvement plans) or hiring a coach for the employee you can quickly conclude it is more cost effective to hire at the 95th percentile through a structured interview process. It is virtually impossible to take an average performer and through training turn them into a corporate star.
* Frank L. Schmidt and John E Hunter, “The Validity and Utility of Selection Methods in Personnel Psychology: Practical and Theoretical Implications of 85 Years of Research Findings,” Psychological Bulletin 124, no. 2 (1998)