The first relevant stream of literature assesses the effect of
online product reviews on sales. Research in this direction
has generally assumed that the primary reason that reviews
influence sales is because they provide information about the
product or the vendor to potential consumers.
Prior research has demonstrated an association between
numeric ratings of reviews (review valence) and subsequent
sales of the book on that site [2], [3], [4] or between review
volume and sales [5], [6], [7]. Indeed, to the extent that
better products receive more positive reviews, there should
be a positive relationship between review valence and sales.
Research also demonstrated that reviews and sales may be
positively related even when underlying product quality is
controlled [3], [5].
However, prior work has not looked at how the textual
characteristics of a review affect sales. Our hypothesis is that
the text of product reviews affects sales even after taking
into consideration the numerical information such as review
valence and volume. Intuitively, reviews of reasonable length,
that are easy to read, and lack spelling and grammar errors
should be, all else being equal, more helpful and influential
compared to other reviews that are difficult to read and have
errors. Reviewers also write “subjective opinions” that portray
reviewers’ emotions about product features or more “objective
statements” that portray factual data about product features,
or a mix of both.