Understanding sentiment analysis
With sentiment analysis, we are concerned with who holds what type of feeling about a specific product or topic. This can tell us, for example, that citizens of a particular city hold positive or negative feelings about the performance of a sports team. They may hold a different sentiment about the team's performance than they do about its management.
Sentiment analysis can be useful in automatically determining the sentiment regarding certain aspects, or attributes, of a product and then displaying the results in some meaningful manner.
This is illustrated using a review of the 2014 Camry from the Kelly Blue Book (http://www.kbb.com/toyota/camry/2014-toyota-camry/?r=471659652516861060), as shown in the following screenshot:
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If you scroll down you can find the expert review about the model shown as following:
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The attributes, such as the overall rating and value, are depicted both as a bar graph and as a numeric value. The calculation of these values can be performed...