Term Extraction Documentation for Yahoo! Search

Important Notice

We are making some changes to the Term Extraction Web Service:

• The service will be only accessible via YQL. If you have been accessing the web service directly, please read the Access via YQL section below to see how to use it via YQL.
• We are launching a more advanced Content Analysis Web Service that will replace the Term Extraction service.

Please migrate to the Content Analysis service as the Term Extraction service will no longer be supported.

Submitting Term Extraction Queries

The Term Extraction Web Service provides a list of significant words or phrases extracted from a larger content.

Request URL

http://search.yahooapis.com/ContentAnalysisService/V1/termExtraction

Note: Due to the context being a potentially lengthy string, Term Extraction requests should be submitted using an HTTP POST request rather than GET. If you plan to use serialized PHP output, consider CURL to post the request rather than PHP's file_get_contents(). You'll then need to remove the HTTP headers before evalutating the code with unserialize().

Request parameters

See information on constructing REST queries

Parameter	Value	Description
appid	string (required)	The application ID. See Application IDs for more information.
context	string (required)	The context to extract terms from (UTF-8 encoded).
query	string	An optional query to help with the extraction process.
output	string: xml (default), json, php	The format for the output. If json is requested, the results will be returned in JSON format. If php is requested, the results will be returned in Serialized PHP format.
callback	string	The name of the callback function to wrap around the JSON data. The following characters are allowed: A-Z a-z 0-9 . [] and _. If output=json has not been requested, this parameter has no effect. More information on the callback can be found in the Yahoo! Developer Network JSON Documentation.

Sample Request (URL: http://search.yahooapis.com/ContentAnalysisService/V1/termExtraction):

appid:

context: Italian sculptors and painters of the renaissance favored the Virgin Mary for inspiration.

query:

Response fields

The schema document for this service response is located at http://search.yahooapis.com/ContentAnalysisService/V1/TermExtractionResponse.xsd

Field	Description
ResultSet	Contains all of the extracted terms.
Result	The text of each extracted term. Terms are returned in order of importance.

Sample response

The following is a sample response for the sample query above:

<ResultSet xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="urn:yahoo:cate" xsi:schemaLocation="urn:yahoo:cate http://search.yahooapis.com/ContentAnalysisService/V1/TermExtractionResponse.xsd"> <Result>italian sculptors</Result> <Result>virgin mary</Result> <Result>painters</Result> <Result>renaissance</Result> <Result>inspiration</Result> </ResultSet>

Access via YQL

The Term Extraction service is available as an YQL table. The table name is search.termextract. The request and response fields are the same as you would use the service directly.

If you are not familiar with YQL, see information on constructing YQL queries.

Rate Limits

The Term Extraction service is limited to 5,000 queries per IP address per day and to noncommercial use. See information on rate limiting.

Terms of Use

Please see our Usage Policy to learn about acceptable uses and how to request additional queries.

Errors

The Term Extraction service returns the standard errors. There are no service-specific errors.

Support & Community

The Term Extraction Search service is discussed on the yws-search-general mailing list.