[tor-talk] panopticlick data

[Joe Btfsplk]

On 9/30/2013 6:14 PM, Joe Btfsplk wrote:
> Info given on panopticlick.eff.org is a bit confusing in that some of 
> it seems incorrect.  If that makes a browser "more common," I guess 
> it's a good thing.
> But some of the info it shows as incorrect is very "uncommon." That 
> doesn't mean someone trying to finger print a browser would get the 
> same info that Panopticlick shows - or does it?
>
> It showed an incorrect screen size and "color depth."  Claiming in 1 
> in 430370 browsers (systems?) have that specific characteristic - 
> fairly uncommon.  Except monitor info is incorrect.
> All that resulted in a claim that "only *one in 1,721,479 browsers 
> have the same fingerprint*."
> https://panopticlick.eff.org
>
> I don't know where / how it gets the screen size, but mine definitely 
> isn't 947 wide.  It's actually a very common size.
>
> I assume the color depth is bit value.  Panopticlick shows 24 (bit?), 
> but there's not even a CHOICE of 24 bit in my display settings, for my 
> monitor / graphics card combination.  Maybe I misunderstand how 
> Panopticlick arrives at that value.
>
> It surprised me that it estimated 1 in 76 browsers had the USERAGENT 
> data given by TBB, of Windows 7 w/ Fx 17.  Other than possibly mostly 
> TBB users going to Panopticlick (skewing the data) to check browser 
> uniqueness, I doubt 1 in every 76 users in the U.S. or world wide, 
> truly have Fx 17 in Windows 7.  Maybe I'm wrong.
>
> I just wondered if others have checked their regular Firefox & TBB 
> uniqueness on eff's site, to see if the data shown seems accurate for 
> their system?
There's something quite odd about the EFF / Panopticlick browser 
fingerprinting site.  All (I) have to do to drastically lower the 
uniqueness of my browser, is revisit the site several time, clearing 
cache between visits.

No cookies are set, so that doesn't affect outcome.  In fact, the "bits 
of identifying information" shown in results chart largely remain 
identical (except screen size sometimes changes), but their estimate of 
"One in X browsers have the  same fingerprint as yours," keeps going 
down dramatically - each time I re run the test.

There's something wrong w/ their "result analysis."  Same browser, 
showing same bits of identifying data, can't go from uniqueness of 1 in 
3 mil, to 1 in 1.7 mil, to 1 in 700 K, to 1 in 500 K, when nothing's 
changed in the parameters that it is recording to arrive at the analysis.