On Thu, Dec 24, 2009 at 6:43 AM, Derek M Jones <de...@knosof.co.uk> wrote:

> Robin,
>  be gamed.  The Turker wants to minimize the work for the money (but if you
>> pay more, they still  do the minimal work but get more money).  So
> My experience of running experiments with software developers is
> that they generally tend to try and minimize the amount of work
> they have to do, even though I they know that it is a 30 minute
> experiment (or xx minutes).  I think it is part of developer make-up
> to try and do things the easy way and in many ways this is
> desirable behavior; who wants to hire a developer who tries to
> do things the hard way?

Yes, but if they can answer the question without doing the (easy) work you
want, Turkers will do that. You need to think about the easiest way to get
to the answer (which might be "flip a coin") and ask if you are OK with that
strategy (it's ideal if this is the strategy you want them to use).  They
seem to have some pride of work, or this is maintained by contracts that
don't pay if you have too many wrong answers, so if the strategy you want is
not much more work than the coin flip strategy, they will do the cognitive
processing you want.

For instance an experiment I ran this year asked developers to
> remember write some code that involved them using either if or
> switch (I was looking to duplicate the findings in figure 2 of
> www.knosof.co.uk/cbook/accu09a.pdf) and remembering some unrelated
> information.
> It looks like they used a fixed strategy for selecting if/switch
> (all but one always used one or the other), concentrating their
> effort on remembering the unrelated information.
>  judgements of "which is better" (that are on the order of a sentence or a
>> paragraph) work well. But even those need some sort of quality control
>> (questions that let you judge whether people are even reading the task or
>> just selecting one answer -- you can refuse to pay people who can't answer
>> those questions right).   Multiple choice quizes work with that caveat.
>>  You
>> might be able to do "find the bug" with simple, short code snippets.
> I am wondering whether non-programmers would attempt the problems and
> just guess the answers.  The monetary rewards are so small that they
> are obviously not the primary motivation, or are we dealing with
> third-world people here?

I honestly don't know where they come from, but given that the typical price
is about $.05/task, I'm guessing that a lot of them are 3rd world. Or maybe
teenagers.  Ed Chi does say that some of the motivation is curiosity and
pride of accomplishment, but that can only go so far.

If you have some way to make sure the programmers aren't "cheating" (not
sure that concept really exists in this domain, but not doing the processing
you need), wouldn't that work as well for non-programmers?  I think that you
can "qualify" people for your study, by asking background questions (which
you pay them to answer, but if they answer the way you want, they get to be
in later studies), but I have no idea how likely they are to lie about their
background.  Maybe your background questions would be knowledge questions
("what does this function return?").

>  So the real question is, can you design your study so that you can get at
>> your research questions with these sorts of tasks?
> My interest is in the cognitive issues that involve less than 10 seconds
> of time, so the Mechanical Turk looks like it might be applicable.

Sounds plausible to me.

>  For someone who has used Mechanical Turk for research purposes, you might
>> look at Ed Chi's work.
> Thanks.  Do you mean this guy?
> http://www2.parc.com/istl/groups/uir/people/ed/ed.htm
Yep.  That publication list is way out of date.  I don't know how much of
his Turker studies have been published (or whether he has published anything
on the methodology).  He gave a talk at my work this week and talked a bit
about how he has done the studies. He'd likely be responsive to an email
asking for more information. He's a big advocate of Mechanical Turk as a
research method.

>> Robin
>> On Wed, Dec 23, 2009 at 6:31 PM, Derek M Jones <de...@knosof.co.uk>
>> wrote:
>>  All,
>>> Has anybody on this list used Amazon's Mechanical Turk
>>> aws.amazon.com/mturk/
>>> to run psychology of programming experiments?
>>> I have no idea how many programmers might be members of this
>>> service.  The list of tasks does not look that technical.
>>> An interesting blog by somebody who has been following this
>>> service:
>>> behind-the-enemy-lines.blogspot.com/
>>> --
>>> Derek M. Jones                         tel: +44 (0) 1252 520 667
>>> Knowledge Software Ltd                 mailto:de...@knosof.co.uk
>>> Source code analysis                   http://www.knosof.co.uk
> --
> Derek M. Jones                         tel: +44 (0) 1252 520 667
> Knowledge Software Ltd                 mailto:de...@knosof.co.uk
> Source code analysis                   http://www.knosof.co.uk

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