With the
rapid expansion of e-commerce, more and more products are sold on the Web, and
more and more people are also buying products online. In order to enhance
customer satisfaction and shopping experience, it has become a common practice
for online merchants to enable their customers to review or to express opinions
on the products that they have purchased. With more and more common users
becoming comfortable with the Web, an increasing number of people are writing
reviews. As a result, the number of reviews that a product receives grows
rapidly. Some popular products can get hundreds of reviews at some large merchant
sites. Furthermore, many reviews are long and have only a few sentences
containing opinions on the product. This makes it hard for a potential customer
to read them to make an informed decision on whether to purchase the product.
If he/she only reads a few reviews, he/she may get a biased view. The large number
of reviews also makes it hard for product manufacturers to keep track of
customer opinions of their products. For a product manufacturer, there are
additional difficulties because many merchant sites may sell its products, and
the manufacturer may (almost always) produce many kinds of products.