| May | JUN | Jul |
| 29 | ||
| 2010 | 2011 | 2012 |
Web wide crawl with initial seedlist and crawler configuration from March 2011. This uses the new HQ software for distributed crawling by Kenji Nagahashi.
What’s in the data set:
Crawl start date: 09 March, 2011
Crawl end date: 23 December, 2011
Number of captures: 2,713,676,341
Number of unique URLs: 2,273,840,159
Number of hosts: 29,032,069
The seed list for this crawl was a list of Alexa’s top 1 million web sites, retrieved close to the crawl start date. We used Heritrix (3.1.1-SNAPSHOT) crawler software and respected robots.txt directives. The scope of the crawl was not limited except for a few manually excluded sites.
However this was a somewhat experimental crawl for us, as we were using newly minted software to feed URLs to the crawlers, and we know there were some operational issues with it. For example, in many cases we may not have crawled all of the embedded and linked objects in a page since the URLs for these resources were added into queues that quickly grew bigger than the intended size of the crawl (and therefore we never got to them). We also included repeated crawls of some Argentinian government sites, so looking at results by country will be somewhat skewed.
We have made many changes to how we do these wide crawls since this particular example, but we wanted to make the data available “warts and all” for people to experiment with. We have also done some further analysis of the content.
If you would like access to this set of crawl data, please contact us at info at archive dot org and let us know who you are and what you’re hoping to do with it. We may not be able to say “yes” to all requests, since we’re just figuring out whether this is a good idea, but everyone will be considered.

Michael W. Lynch
The FTC's creative market definitions
Virginia Postrel
Who do they think they're fooling?
Brian Doherty
Brian Doherty
Brian Doherty
Jacob Sullum
Jacob Sullum
Jeff Taylor
Kenneth Lloyd Billingsley
Lisa Snell
Nick Gillespie
Rick Henderson
Rick Henderson
Nick Gillespie
Charles Oliver
Thomas W. Hazlett
How consumer activists sabotage ATM customers
Michael W. Lynch
Congress would rather complain about life-tenured federal judges than make recalcitrant bureaucrats enforce the law.
Daniel J. Mitchell
Squabbling between flat taxers and sales taxers could allow the Internal Revenue Code to escape unscathed.
Walter Olson
Redefining yesterday's green light as red
Henry Payne
How green ideology denies poor blacks good jobs
John J. Pitney, Jr.
Why campaign contributions aren't as corrupting as you think
Brian Doherty
For today's independent artists, integrity can be financially rewarding. Can punk rock and alternative comics make peace with entrepreneurial capitalism?
Michael Fumento
New air pollution regulations based on questionable science and creative economic analysis could cost billions and change the way Americans mow their lawns, heat their homes, clean their clothes, and barbecue their burgers. Can Congress stop this regulato
Amy Sherman
Can private charities replace tax-funded welfare? A program in one Maryland county suggests the challenges facing church-based efforts to help welfae mothers become self-sufficient.
Robert Poole
Gregory Clark
James V. DeLong
T. Markus Funk
John J. Pitney, Jr.
Rick Henderson
Rick Henderson

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