I found the article very interesting, but it seems to me that the metrics are the wrong ones. You cannot treat hire and no hire outcomes equally. Let's not forget that the goal of the interview process is to actually hire people. A successful hire is worth millions, a correct no-hire decision is just avoiding further losses of time and money. On the other hand, in terms of efficiency, a candidate that wasn't rejected early is the most expensive error. Well, not as expensive as actually hiring the wrong person, but it usually takes months to figure that out. Whereas the fact that a whole man-day was spent interviewing the wrong person on site becomes obvious in a few hours.

Here are the important metrics in my opinion, in order of decreasing importance:

- How many people were hired? Or what percentage of positions were filled? How long does it take to fill a position? Nothing in the article mentioned how many people were actually hired.

- False positives (people making it to the most expensive stage of the interview, typically a day-long on site interview, and being rejected there). What percentage of people that went to on site interviews got offers? Personally, I have always advocated processes that eliminate as many false positives as possible, even if it comes at the cost of some false negatives. Of course, you have to be careful not to filter out people too aggressively, because then you're just not going to hire anyone.

- False negatives (incorrectly rejecting good candidates early). By definition that's impossible to measure exactly. However, if you are not hiring fast enough, then maybe you have a problem with your screening process. At this point you could do an experiment and relax the screening process for half of the candidates and see what happens. But it could be just a sourcing problem, that is, you are not getting good candidates in the pipeline to begin with. It's very hard to tell whether you are being too harsh and not believing enough in people's abilities (or not willing to develop talent), or you are just not attractive to the kind of people that you want to hire.

Of course, all of the above is from the employer's point of view. If you are also trying to provide job seekers with a good service, then you can devise other metrics for success and for efficiency from their perspective.

(edited for formatting)