I. Introduction
Nowadays, the boom of e-commerce has led to an increasing preference for online shopping. In order to better manage products and provide services to customers, such as classifying products and recommending products, e-commerce platforms need to understand entities in the product titles, such as brand names (Apple, Nike, etc.), product names (iPhone, shoes, etc.) and other features (colors, sizes, etc.). This task is usually formulated as entity typing, which is to classify entity types given the entity and context. For example, a product title ‘NAGANO Set of 2 Chairs’ in Table I has ‘NAGANO’ as a brand name and ‘Chairs’ as a product name. Thus the entity typing task is to classify ‘NAGANO’ and ‘Chairs’ into ‘brand name’, ‘product name’ or ‘feature’ based on the product title.