Minimum match and phrase slop

Influence search relevancy by using minimum match and phrase slop.

Minimum match

Specifies the number of search keywords required to match the indexed document, when the ANY search type is used. A number denotes the number of query keywords to match. A number that is formulated with a percentage denotes that a percentage of the query keywords must match.

• 1 denotes that at least one query keyword must match.

• 2<80% 6<50% denotes that when there are fewer than 3 keywords, both of the keywords must be found in the document. When 3 - 6 keywords occur, 80% of the keywords must be found in the document. When there are more than 6 keywords, 50% of the keywords must be found in the document.

  For example, if a shopper searches for 3 keywords, 80% of the 3 keywords equals 2.4. Rounded down, results that match at least 2 of the 3 entered keywords are returned.

  Important: We must use the correct character encoding when you enter percentage values in a file. For example:

  • In a JSP fragment file, such as SearchSetup.jspf, the preceding percentage value is entered as is: 2<80% 6<50%.

  • In the wc-component.xml file, such as in this case, wc-component.xml, the preceding percentage value is entered as: 2&lt;80% 6&lt;50%.

For more information about the specification format, see Minimum Number Specification Format.

For more information about setting values within the component configuration file, see Changing properties in the component configuration file (wc-component.xml). Depending on the length of the query sent to Solr, minMatch calculates the minimum number of terms that must match before products are returned. For example, if shopper's search query contains 6 terms, the following values might be used:

• mm=2: products whose indexed fields contain at least 2 out of the 6 terms are returned

• mm=50%: products whose indexed fields contain at least 3 out of the 6 terms are returned

• mm=10: Solr lowers mm to 6 (to match query length), and products that match all 6 terms are returned

Note: If you use minimum match, IBM recommends enabling the runtime query expansion algorithm. This algorithm is primarily used with minimum match and search term associations; however, we can also enable the algorithm regardless of the search features that the site uses. Multiple-word search results are improved because the query is enclosed within parentheses and the query length is better controlled. See Combining minimum match with search term associations (using the query-time expansion algorithm).

Phrase slop

Specifies how far apart the indexed search terms are in the document to influence relevancy. Phrase slop defines the amount of slop on phrase queries that are built for phrase fields.

For example, if you set a phrase slop of 1 for the red shirt search term then red shirt is more relevant than red striped long sleeve shirt.

Related tasks
Tuning multiple-word search result relevancy by using minimum match and phrase slop
Combining minimum match and search term associations