In 2003 Luis Von Ahn introduced The ESP Game, which challenged
two players working online to independently pick the same words to
describe a picture. But The ESP Game was also designed with a covert
purpose: to improve search technology and the accessibility of the Web
by gathering metadata about untagged internet images. Impressed by the
game, Google picked it up and renamed it Google Image Labeler.
Von Ahn, a professor at Carnegie Mellon University and recipient of the
Macarthur Fellowship, has since built out a collection of similar
“Games with a Purpose“. I spoke with him recently to discuss the
theory behind his work and his vision for how it can change the way we
approach the design of user interfaces.
Q: So what are “Games with a Purpose”?
A: To the player a GWAP is for all purposes a game, but
as a side effect of play it’s designed to produce useful work.
Why build something like Google Image Labeler as a game? Why not just
show people a picture and ask them to submit tags for it?
A: Well, because
nobody would do it. There has to be motivation for doing work. There
are a few ways you can provide that. You can pay people for work, and
that’s effective but it’s also expensive. Then there are motivations that drive
people to contribute to something like Wikipedia, perhaps
because they believe it’s a worthwhile thing or because they like the feeling
that they played a personal part in building it. But that model has
failed when people have tried to apply it in other contexts, so it’s
not a reliable motivator. Then there are things that people do because
they enjoy them. So with GWAPs, instead of paying people with money
you pay them with entertainment.
Q: How much can you accomplish by playing games?
A: On average, Americans
spend 1 hour every day playing videogames. That’s over 100 billion humanhours a year. That’s a
humongous opportunity, considering that it only took 7 million
humanhours to construct the entire Empire State Building. And consider
too that while people are spending all that time playing games they’re
using their brains. If you could turn all gameplay into useful work,
people would be amazingly productive.
Q: If people are just playing around, then how do you know that the results are of good quality?
There are a couple of tricks to that. First, you can correlate one
player’s results with those of other unrelated players. For example,
in The ESP Game the same image will be shown to multiple players who
are asked to submit tags describing it. Since those players have never
met and never had the opportunity to interact, if more than one person
gives the exact same answer then it’s much more likely to be a reliable
tag for the image. Second, you can give players questions for which
you already know all possible correct outputs, to see if they’re
answering honestly. If their responses fall outside of the set of
correct outputs, then you can flag them as suspicious and ignore the
rest of their responses.
Q: Since you started promoting
Games with a Purpose, do you feel that the use of GWAPs has progressed
as you’d envisioned in the broader community of design practitioners?
and no. I think it has been catalytic to what is today called
“crowdsourcing”, which didn’t even have a name when we started. But
games haven’t gotten to the point where I’d like them to be.
Ultimately I’d like to see all work turned into a game (I don’t see why
it couldn’t be), but we’re not there yet. That’s probably because it’s
very, very hard to design a good game. Once you add in the constraint
of the game producing useful work, then it becomes even harder. The
potential’s there, but I think designers are just starting to figure
out how exploit it.
Q: So how do you go about designing games?
first we just think about them. We think about them a lot. Then we
build a prototype using just paper and pencil, and start testing it
like hell. You really can’t tell whether a game will be fun or not
until you test it. And if you find that it is fun then you build a
simple live version and test that, revise it, and so on. And even then
there’s no guarantee that it people will enjoy it. Of the games that
you complete, you’ll find that some are much more fun than others.
Q: Can you talk a bit about fun?
Actually I’m not sure how to define the word “fun”. What really
matters is whether or not people play the game. It’s a strange paradox
that people will often play a game that they don’t even find
enjoyable. So I prefer to sidestep philosophical questions about
whether or not people are really having fun, and focus on what we can
This is a spectacular direction for user experience design. Thanks so much for your time!
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