View source for OpenCalais classifier

'''OpenCalais classifier has been retired in Wandora version 2015-08-06 after Calais' API changes.'''

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[http://www.opencalais.com/ http://www.wandora.org/wandora/images/calais_logo_final_thomson_web_100.jpg]
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OpenCalais classifier takes a text fragment and creates a topic for it, and associates created text topic with keywords given by [http://www.opencalais.com/ OpenCalais] web service. The effect is that given text is tagged with certain topics found in the text.

Wandora's OpenCalais classifier starts with '''File > Extract > Classification > OpenCalais classifier...'''. Classifier can read given file, URL, or plain text.

[[Wandora Firefox plugin|Wandora's Firefox plugin]] can also access the OpenCalais classifier. You can send complete WWW page or just WWW page selections to Wandora for OpenCalais classification while browsing the web.
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== OpenCalais classification example ==

Although OpenCalais classifier works also within Wandora application, this example demonstrates OpenCalais classifier in Wandora's web browser extension. In our example user has started Wandora application and [[Embedded HTTP server|Wandora's embedded HTTP server]]. Then user browses The New York Times web site and finds interesting text fragment discussing Senator Obama's speech. User selects the text fragment (See image below) and starts Wandora Firefox plugin with option '''Classify with OpenCalais'''.


[[Image:opencalais_example_1.gif|center]]


Plugin sends the text to Wandora's OpenCalais classifier. Classifier passes the text to OpenCalais web service and receives keywords found in the text. Finally Wandora creates topics for

* The text selection
* WWW page the text fragment originates
* Each keyword provided by the OpenCalais

and links everything with reasonable associations. Below is a screenshot of Wandora after successful classification. It appears OpenCalais recognized keywords '''Obama''' and '''McCain''' in the given text fragment.


[[Image:opencalais_example_2.gif|center]]

== Additional notes ==

* The quality of keywords provided by OpenCalais varies. Sometimes OpenCalais doesn't recognize obvious keywords in given text. Sometimes provided keyword set is very comprehensive.
* OpenCalais classifier accepts only limited size texts.
* OpenCalais classifies properly only English language texts.

== See also ==

* [[Tagthe extractor]]
* [[Yahoo! YQL term extractor]]
* [[SemanticHacker classifier]]
* [[AlchemyAPI extractors]]
* [[Zemanta extractor]]
* [[GATE/ANNIE integration|GATE/ANNIE]]
* [[Stanford Named Entity Recognizer integration|Stanford Named Entity Recognizer (NER)]]
* [[UClassify integration]]