Chesapeake Digital Preservation Group’s 5th Annual Investigation of Link Rot and Legal Resources on the Web

The Chesapeake Digital Preservation Group — with participating libraries including the Georgetown University Law Center Library, the Harvard Law School Library, the Maryland State Law Library and the Virginia State Law Library — has recently posted its 5th Annual investigative report

“Link Rot” and Legal Resources on the Web: A 2012 Analysis by the Chesapeake Digital Preservation Group

Some highlights:

Data Show Link Rot in 38 Percent of Online Publications within Five Years

• In 2012, 218 out of 579 URLs in the sample no longer provide access to the content that was originally selected, captured, and archived by the Chesapeake Group. In other words, link rot has increased to 37.7 percent within five years.
• In 2008, the sample was analyzed for the first time as part of an evaluation of the archiving program, and link rot was found to be present in 48, or 8.3 percent, of the 579 URLs comprising the sample. At the time, a total of 1,266 web-based titles had been captured and archived. A random sample of 579 titles from the archive was generated for the analysis, ensuring results at a 95 percent confidence level and confidence interval of +/- 3.
• One year later, in 2009, the sample was analyzed a second time. Link rot was found to be present in 83 out of the original sample of 579 URLs. Within two years of capture, 14.3 percent of the archived titles had disappeared from their original URLs.
• By the third year, in 2010, the prevalence of link rot had increased to 160 out of 579 URLs, to a whopping 27.9 percent. Link rot continued to increase in 2011, but by a slower margin, reaching 30.4 percent by the fourth year. The new 2012 data show an increase of 7.3 percent compared to 2011, to 37.7 percent, more in line with our findings of annual increases from 2008 and 2009.

Cross-posted on Law Library Blog.