job screening question

Bryan Irvine sparctacus at
Sat Jul 7 04:25:55 UTC 2012

On Sat, Jul 07, 2012 at 02:06:58PM +1000, Matthew Palmer wrote:
> On Sat, Jul 07, 2012 at 12:51:55PM +1200, Ben Aitchison wrote:
> > On Fri, Jul 06, 2012 at 04:18:21PM +1000, Matthew Palmer wrote:
> > > On Thu, Jul 05, 2012 at 05:01:39PM -0700, Scott Weeks wrote:
> > > > --- jason at wrote:
> > > > From: Jason Baugher <jason at>
> > > > 
> > > > Geez, I'd be happy to find someone with a good attitude, a solid work 
> > > > ethic, and the desire and aptitude to learn. :)
> > > > ---------------------------------------
> > > > 
> > > > 
> > > > Yeah, that.  But how do you get those folks through the HR 
> > > > process to you, so you can decipher their skill/work ethic 
> > > > level?  What can the HR person ask to find out if someone 
> > > > has these qualities?  OSPF LSA type questions will not help.
> > > 
> > > Don't get HR to do that sort of screening.  They suck mightily at it.  I
> > > lack any sort of HR department to get in the way, and I'm glad of it -- I
> > > don't see the value in having someone who doesn't know anything about the
> > > job get in the way of finding the right person for it.  Sure, get 'em to do
> > > the scutwork of posting job ads, collating resumes, scheduling things and
> > > sending the "lolz no!" responses, but actually filtering?  Nah, I'll do that
> > > bit thanks.  If you have to have HR do a filter call, make it *really*
> > > simple, like "What does TCP stand for?" -- sadly, you'll still probably
> > > filter out half the applicants for a senior position...
> > 
> > I've noticed a strong correlation between people who don't know what acronyms
> > stand for, and competence.  People who don't know anything try and figure out
> > what the acronym stands for - people who want to understand things see it as
> > just a place holder.
> [...]
> > Maybe it's more significant to ask what the difference between TCP and UDP is.
> Yes, the difference between TCP and UDP is a much better question to ask,
> but having HR assess and act on the answer to the question is a whole hell
> of a lot harder.  In many ways, *that's* the tough bit of finding a good
> screening question. 
Indeed.  I was once filtered out of a sysadmin job at a big search engine company.
They asked questions like:
What system call does the ls command make?
I didn't know, but said you could read the source or strace to find out.

They asked me to describe what ARP is.
I basically talked about what an ARP table is and went into detail about "who-has" requests for building the table etc... 

and more questions like that.  They seemed lost and didn't seem to know what I was talking about.  It was at this point I realized that I was talking to an HR screener. The conversation was awkward from this point on as I struggled to attempt to guess what might be on the piece of paper as "The Right Answer". Needless to say I didn't hear back. Was I what they were looking for? Maybe, maybe not. But I was screened out before either of us could find out.  Just as well, I'm much happier where I am now. :-)

> Finding good interview questions *in general* isn't all
> that hard.  With a good senior candidate my interview questions could just
> be bringing up problems I've recently solved or am currently wrestling with,
> and having a 30 minute conversation on the problem.  I'll get a very good
> idea of someone's domain knowledge and problem-solving skills by doing that. 
> But there's no way I can ask HR to do that, because they don't know how to
> assess the answer, and as previously demonstrated ("fragmented disks",
> indeed), you can't have HR act as scribe and relay the answer to you,
> because they'll get it wrong, and the interesting bit is the *conversation*,
> not the canned single-shot answer.

Definitely. I like the describe difference between UDP/TCP question.  Another fave of mine is "Give me a list of various acronyms and its associated port" and give them HTTP/80 as an example. Many interviews end shortly after this one.

> That's my motivation for asking a question as inane as "What does TCP stand
> for?" -- it has an overwhelmingly obvious answer that can be verified in a
> second or two by someone who really doesn't know anything about what they're
> asking.  Give a candidate 10 of those sorts of questions over the phone from
> an HR drone, if they score 8-or-better (for instance) they pass and you get
> to see their resume.  That is, of course, assuming your organisation is so
> screwed up that they won't let you at candidates directly (which is still my
> preferred option -- leave HR to do the paperwork).

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