frecency

English

Etymology

Blend of frequency +‎ recency, coined for the development of Mozilla Firefox.

Pronunciation

• IPA^(key): /ˈfɹiːsənsi/

Noun

frecency (countable and uncountable, plural frecencies)

1. (computing, rare) Any heuristic that combines the frequency and recency into a single measure, typically used to predict page revisits in a web browser.
   • 2008 February 13, Mark Raby, “Firefox 3 Beta 3 goes live”, in TG Daily:

     For example, a feature called "frecency" compiles the user's browing^[sic] history to suggest similar websites and searches.

   • 2008 April 17, Deb Richardson, quoted in Bill Scott and Theresa Neil, Designing Web Interfaces,^[1] O’Reilly Media (2009), →ISBN, page 264:

     […] the AwesomeBar will match what you’re typing (even multiple words!) against the URLs, page titles, and tags in your bookmarks and history, returning results sorted by “frecency” (an algorithm combining frequency + recency).

   • 2008 August, unknown author, “Firefox 3: A Browser Odyssey”, Maximum PC, Future US, ISSN 1522-4279, page 52:

     So the more often and the more recently you’ve been there, the higher “frecency” it has and the higher it’s rated.

   • 2009 March 23, Mike Beltzner, “Re: Firefox privacy prefpane UI refresh”, in mozilla.dev.apps.firefox‎^[2] (Usenet):

     […] or improve our cache performance so that we're keeping cached items that are related to sites with high frecency -- […]

   • 2009 May 20, Ron K., “Re: Address selection preference”, in mozilla.support.thunderbird‎^[3] (Usenet):

     No, Tb [Thunderbird] has yet to develope^[sic] the Fx [Firefox] frecency thing. It's just simple pattern matching, IIUC.

   • 2010, Mounia Lalmas et al., editors, Research and Advanced Technology for Digital Libraries […] , Springer, →ISBN, page 544:

     Regarding collection usage, frecency metrics are employed, combining frequency and recency, to effectively capture concept drift and temporal trends.

Further reading

• frecency on Wikipedia.Wikipedia
• adaptive replacement cache on Wikipedia.Wikipedia
• https://wiki.mozilla.org/User:Mconnor/Past/PlacesFrecency
• https://web.archive.org/web/20080206120916/http://developer.mozilla.org/en/docs/Places:Awesomebar