[Wikiquality-l] Wikipedia colored according to trust

[Luca de Alfaro]

Daniel is making some very good points.

Our current algorithm is vulnerable to two kinds of attacks:

   - Sock puppets
   - People who split an edit into many smaller ones, done with sock
   puppets or not, in order to raise the trust of text.

We think we know how to fix or at least mitigate both problems.  This is why
I say that a "real-time" system that colors revisions as they are made is a
couple of months (I hope) away.  The challenge is not so much to reorganize
the code to work from wikipedia dumps to real-time edits.  The challenge for
us is to analyze, implement, and quantify the performance of versions of the
algorithms that are resistant to attack.  For those of you who have checked
our papers, you would have seen that not only we propose algorithms, but we
do extensive performance studies on how good the algorithms are.  We will
want to do the same for the algorithms  for fighting sock puppets.

About the proposal by Daniel: time alone does not cover our full set of
concerns.
I can every day use identity A to erase some good text, and identity B to
put it back in. Then, the reputation of B would grow a bit every day, even
though B did not do much effort.
We are thinking of some other solutions... but please forgive us for keeping
this to ourselves a little bit longer... we would like to have a chance to
do a full study before shooting our mouths off...

Luca

On Dec 19, 2007 6:05 PM, Daniel Arnold <arnomane at gmx.de> wrote:

> Hello Luca,
>
> >    1. The trust coloring rightly colored orange (low-trust) some
> >    unreliable content,
>
> Yes I was lost in translation. ;-)
>
> >    2. and the Wikipedia people were quick in reverting it.
>
> Yes.
>
> > Note that we also highlight as low trust text that is by anonymous
> > contributors. The text will then gain trust as it is revised.
>
> One possible weakness came into my mind after I also read your paper. Your
> algorithm is perhapes a bit vulnerable to "sock puppets". Imagine person A
> with one account and person B with two accounts. Both have a medium
> reputation value for their accounts. User A edits an article with his
> account
> 4 times. All 4 subsequent edits are taken together and the article has a
> maximum trust value according to the user's reputation. User B makes as
> well
> 4 edits to an article but switches between his accounts and thus "reviews"
> his own edits. If I understand your algorithm correctly the sock puppeted
> article is trusted more than the other one.
>
> Quite some time ago I reflected how to avoid incentives for sock puppets
> in
> karma systems without even knowing which accounts are sock puppets:
> http://meta.wikimedia.org/wiki/Meritokratischer_Review (sadly in German
> ;-).
> The system described there differs from your approach but the idea on how
> to
> avoid incentives for sock puppets without even knowing who a sock puppet
> is
> could perhapes adapted to your system.
>
> The basic idea for a sock puppet proof metric is is that a person has only
> a
> limited amount of time for editing (I don't consider bots cause they are
> easily detectable by humans). A single person needs the same time for e.g.
> 4
> edits (in the following I assume each edit has the same length in bytes)
> regardless how much accounts are used but two different people with each 2
> edits only need half of the (imaginary) time (you don't need to measure
> any
> time untits at all).
>
> So the maximum possible reliability person B can apply to the article with
> its
> two accounts (let us say each acount has 2 edits = 4 total edits) has to
> be
> the same as the one which is possible with person A's single account (4
> edits). So in general two accounts with each X edits should never be able
> to
> add more trust to an article than one person with 2*X edits (note: edit
> count
> number is only for illustration, you can take another appropriate
> contribution unit).
>
> > About 2, I am very glad that bad edits are quickly reverted; this is the
> > whole reason Wikipedia has worked up to now.
> > Still, it might be easier for editors to find content to check via the
> > coloring, rather than by staring at diffs.
>
> That's certainly true for articles not on your watchlist (or bad edits
> that
> were forgotten and are still the latest version).
>
> >   - Finding when flagged revisions are out of date (there may be a new
> >   high-trust version later)
>
> Well as I said I'd love to see flagged revisions and your system combined
> (in
> a way described by my previous mail). An automated system probably always
> has
> some weaknesses some clever people can abuse but it is very fast, while a
> hand crafted system depends on the speed of individual persons but is much
> harder to fool.
>
> > BTW, as the method is language-independent, we look forward to doing the
> > same for wikipedias in other languages.
>
> Good to know. :-)
>
> Arnomane
>
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>
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