At google's scale, if they had an alternative basis for hiring people they could judge candidates by both and hire randomly use one method or the other method to make some of their hires, then compare their performance over time and at least say if there is a significant difference or not.
But as you note, the lack of obvious good alternatives is an issue... and we can't pretend that there isn't an enormous difference among candidates. If we though that unfiltered candidates were broadly similar then "hire at random, dismiss after N months based on performance" would be a great criteria, but I don't think anyone who has done much interviewing thinks that would be remotely viable.
(Though perhaps the differences between candidates are less than we might assume based on interviewing since interviewees should be worse than employment pool in general, since bad candidates interview more due to leaving jobs more often and taking longer to get hired)
>If we though that unfiltered candidates were broadly similar then "hire at random, dismiss after N months based on performance" would be a great criteria, but I don't think anyone who has done much interviewing thinks that would be remotely viable.
I know a fair number of companies that do essentially that. They hire contractors for 6 months, at the end of 6 months the good ones are offered a full time position. The contractor company probably does some form of interview, but they are more interested in their 6 months of overhead from the contractor than quality candidates.
> since bad candidates interview more due to leaving jobs more often and taking longer to get hired
But there are also great people who interview badly.
But as you note, the lack of obvious good alternatives is an issue... and we can't pretend that there isn't an enormous difference among candidates. If we though that unfiltered candidates were broadly similar then "hire at random, dismiss after N months based on performance" would be a great criteria, but I don't think anyone who has done much interviewing thinks that would be remotely viable.
(Though perhaps the differences between candidates are less than we might assume based on interviewing since interviewees should be worse than employment pool in general, since bad candidates interview more due to leaving jobs more often and taking longer to get hired)