1 / 6

Search engine note

Search engine note. Search Signals. “ H euristics” which allow for the sorting of search results Word based: frequency, position, … HTML based: emphasis, Header URI based: server name, URL Page based: Not dependent on the Search term, but on the page features PageRank the most important

elton
Download Presentation

Search engine note

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Search engine note

  2. Search Signals • “Heuristics” which allow for the sorting of search results • Word based: frequency, position, … • HTML based: emphasis, Header • URI based: server name, URL • Page based: Not dependent on the Search term, but on the page features • PageRank the most important • Search results are a combination of these

  3. Anchor text • Other pages, images, documents, etc. are linked via “anchors” • E.g. <a …>, <img …>, etc • Text around the anchor describes the linked page • <a href=“http://www.cowabduction.com”> UFOs are stealing our cows! </a> • These words index to the LINKED page

  4. Search “algorithm” • Single or multi-word • For every word in query • Find the pages the word occurs on and compute • Group 1: Pages with all those words (intersection) • Group 2: Pages with any of those words (union) • For every page in the returned set • Sort by formula • k1 * signal1 + k2 * signal2 + … +kn * signaln • (k’s sum to 1 is advantageous computationally)

  5. Indexes • Search index • For every page, what words occur on that page • Plus “features” of word occurance (location, html, etc) • Inverted (reverse) index • For every word, what pages it occurs on

  6. Summary • http://www.youtube.com/watch?v=fnSJBpB_OKQ

More Related