This week there was an interesting conversation over on Slashdot.  The subject of the post is an age discrimination suit against Google.  However, the discussion has gone to other interesting places.  The question is being asked if there is a difference in the way you should interview experienced people vs. those just out of school.  It reflects something I've come to understand after years of interviewing.  The software/IT industry is relatively young.  This is true both in terms of the workforce and the maturity of the work ecosystem.  The result of this is that we don't tend to have very sophisticated interview processes.  To be sure, they are good, but they are not flexible enough.  They are aimed at hiring the young hotshot recent graduate.  They are not usually designed to find someone with experience.  That will have to change as the median experience in the industry raises.

What is it that biases interviews toward those recently in school?  The questions we ask favor those who have graduated in the near past over those who have been in the industry for a decade or two.  It is pointless to ask a newly minted graduate about his/her experience.  They will likely have a few group projects and perhaps a summer internship to talk about, but the projects are all limited in scope.  Even someone who has been in the workforce for a few years will likely have been implementing someone else's design.  Assessing non-trivial design skills is hard and still harder in an hour-long interview.  So often we don't evaluate this.  Instead, we turn to the easily measurable.

We, as an industry, tend to ask a lot of questions that are more about particular knowledge than about problem solving skills.  Sure, we couch them in terms of problem solving skills, but they are really about particular knowledge.  Asking someone to describe OS internals (processes, memory, garbage collection, etc.) is biased toward someone who has recently taken an OS class or the few who work on the guts of operating systems.  It's not that most experienced people can't understand them, it is that they don't need to.  Many coding questions are about syntax or simple tasks no one faces in real life.  Asking someone to swap the words in a string without using extra memory isn't about problem solving as much as it is about knowing the trick.  Expecting someone to be able