Inferring Networks of Substitutable and Complementary Products

In a modern recommender system, it is important to understand how products relate to each other. For example, while a user is looking for mobile phones, it might make sense to recommend other phones, but once they buy a phone, we might instead want to recommend batteries, cases, or chargers. These two types of recommendations are referred to as substitutes and complements: substitutes are products that can be purchased instead of each other, while complements are products that can be purchased in addition to each other. Here we develop a method to infer networks of substitutable and complementary products. We formulate this as a supervised link prediction task, where we learn the semantics of substitutes and complements from data associated with products. The primary source of data we use is the text of product reviews, though our method also makes use of features such as ratings, specifications, prices, and brands. Methodologically, we build topic models that are trained to automatically discover topics from text that are successful at predicting and explaining such relationships. Experimentally, we evaluate our system on the Amazon product catalog, a large dataset consisting of 9 million products, 237 million links, and 144 million reviews.Comment: 12 pages, 6 figure

Result Enrichment in Commerce Search using Browse Trails

Commerce search engines have become popular in recent years, as users increasingly search for (and buy) products on the web. In response to an user query, they surface links to products in their catalog (or index) that match the requirements specified in the query. Often, few or no product in the catalog matches the user query exactly, and the search engine is forced to return a set of products that partially match the query. This paper considers the problem of choosing a set of products in response to an user query, so as to ensure maximum user satisfaction. We call this the result enrichment problem in commerce search. The challenge in result enrichment is two-fold: the search engine needs to estimate the extent to which a user genuinely cares about an attribute that she has specified in a query; then, it must display products in the catalog that match the user requirement on the important attributes, but have a similar but possibly non-identical value on the less important ones. To this end, we propose a technique for measuring the importance of individual attribute values and the similarity between different values of an attribute. A novelty of our approach is that we use entire browse trails, rather than just clickthrough rates, in this estimation algorithm. We develop a model for this problem, design and (theoretically) analyze our algorithm for solving it using browse trails, and support our theoretical findings by showing, via experiments conducted on actual user data, that the algorithm performs well in practice. In the course of developing our algorithm, we offer a solution to another problem that might be of independent interest: we give an algorithm for the annotation of web domains by a set of keywords that represent the contents of the domain. 1