Sorting Results: Searching time-sensitive documents
The search engine can be made to give special weight to recently-modified documents. This is the "sorting: time sensitive" feature. It is not enabled by default.
The search engine first determines the relevancy ranking of a document like it normally does, counting the number of times keywords appear in the text.
Then, when this feature is enabled, the search engine computes the time since the document was last modified.
If the document was modified within the last two days, its base relevancy will be multiplied by 4. If modified within the last four days, its relevancy will be modified by 3. If modified within the last 8 days, its relevancy will be multiplied by 2.
The search results will then be returned to the visitor, sorted by their modified relevancy values.
(For more on how base relevance is calculated, see Sorting Results: How relevance is calculated)
A news web site contains ten articles which match keyword "election". One was added yesterday and contains the word three times. The others are all from last year, but each contains the word from four to ten times.
Without the "sorting: time sensitive" feature, the most recent article would appear near the end of the search results, because the keyword appears more often in the older articles.
With the "sorting: time sensitive" feature, the relevance of the most recent article is multiplied by 4, since it was modified within the last two days. Its adjusted relevance is now 12, and it appears at the top of the search results list.
After a week or so, the new article will stop receiving this special treatment because it will be more than 8 days old, and then the older article which mentions "election" ten times will once again be at the top of the list.
Enabling this Feature
This feature can be enabled globally, or visitors can enable it on a search-by-search basis.
To enable for all searches, go to "Admin Page" => "User Interface" => "User Interface-Related Settings" => "Sorting: Time Sensitive". Set the value to 1 by checking the checkbox.
To allow visitors to enable this feature on a search-by-search basis, add the following HTML form fields to your searchform:
<p> <input type="hidden" name="p:ts_udav" value="0" /> <input type="checkbox" name="p:ts" value="1" /> Show more recent documents first. </p>
Note that the special hidden field "p:ts_udav" is required. FDSE uses this to properly persist the user's preferences if there are multiple pages of search results.
If the search engine has been configured to sort results by last modified time or last indexed time, then this feature will have no effect. This feature works only when the search engine is sorting by relevance or reverse relevance.
(See Sorting search results for more information about sorting by last-modified or last-indexed time.)
Note that, in many cases, FDSE is not able to properly calculate the last modified time of documents. In these cases, it uses the "last indexed time" in place of the last modified time. Because of this, you should only use the "time sensitive" feature when you know that your documents are returning valid last modified times, or when the most recently indexed documents are also of special relevance to the visitor.
History: this feature was added in version 2.0.0.0054.
"Sorting Results: Searching time-sensitive documents" http://www.xav.com/scripts/search/help/1131.html