A phrase-based opinion list for the German language
We present a new phrase-based generated list of opinion bearing words and phrases for the German language. The list contains adjectives and nouns as well as adjective-and noun-based phrases and their opinion values on a continuous range between −1 and +1. For each word or phrase two additional quality measures are given. The list was produced using a large number of product review titles providing a textual assessment and numerical star ratings from Amazon.de. As both, review titles and star ratings, can be regarded as a summary of the writers opinion concerning a product , they are strongly correlated. Thus, the opinion value for a given word or phrase is derived from the mean star rating of review titles which contain the word or phrase. The paper describes the calculation of the opinion values and the corrections which were necessary due to the so-called " J-shaped distribution " of online reviews. The opinion values obtained are amazingly accurate .