Difference between revisions of "Talk:2009-04-24 48 11"

From Geohashing
imported>Zb
(New page: Flippin' weird: Is it just me, or is Mammendorf is just as preferred by the random (?) Geohash algorithm as the surroundings of Munich's airport? 2008-07-23 48 11 2009-04-03 48 11 ...)
 
imported>Ekorren
(Birthday paradox.)
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[http://irc.peeron.com/xkcd/map/map.html?date=2009-04-24&lat=48&long=11&zoom=9&abs=-1 Map of 2009-04-23]
 
[http://irc.peeron.com/xkcd/map/map.html?date=2009-04-24&lat=48&long=11&zoom=9&abs=-1 Map of 2009-04-23]
 
--[[User:Zb|Zb]] 20:07, 23 April 2009 (UTC)
 
--[[User:Zb|Zb]] 20:07, 23 April 2009 (UTC)
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:I believe noone has exactly examined that yet, but basically those repetitions seem to be an application of the [http://en.wikipedia.org/wiki/Birthday_Paradox Birthday Paradox]. In our latitudes, the chance is about 3.8%, i.e. once in four weeks in average, that two consecutive coordinates are within of 10 km of another. The chance for a 10 km range repetition within of one week is already about one fourth. --[[User:Ekorren|Ekorren]] 21:29, 23 April 2009 (UTC)

Revision as of 21:29, 23 April 2009

Flippin' weird: Is it just me, or is Mammendorf is just as preferred by the random (?) Geohash algorithm as the surroundings of Munich's airport? 2008-07-23 48 11 2009-04-03 48 11 Map of 2009-04-23 Map of 2009-04-23 --Zb 20:07, 23 April 2009 (UTC)

I believe noone has exactly examined that yet, but basically those repetitions seem to be an application of the Birthday Paradox. In our latitudes, the chance is about 3.8%, i.e. once in four weeks in average, that two consecutive coordinates are within of 10 km of another. The chance for a 10 km range repetition within of one week is already about one fourth. --Ekorren 21:29, 23 April 2009 (UTC)