Abstract: The existed studies of online reviews have been carried out under the background where consumers cannot make positive comments and negative comments for the same goods separately While similar comment system like “zolcomcn” has already allowed consumers to offer both positive and negative comments separately, and makes it possible for customers to show their reviews by pictures The impact of online reviews which distinguish positive comments and negative comments and the observational learning behavior based on the reviews by picture on the usefulness of online reviews is studied Conclusions show that the extreme of star ratings, the review length, and the reviews by picture have significant effect on the usefulness of online reviews under the distinguishing background; the impact of negative online reviews is greater than that of the positive ones

Key words: word-of-mouth, online reviews, sentimental orientation, observational learning, consumer decision-making