1. A method implemented with an electronic device for identifying other documents similar to a particular document or for identifying other documents similar to a set of documents, the method comprising: associating a weight with each of a plurality of information types and persisting the weights in the electronic device; identifying information types within each of the documents; and estimating a similarity value or a set of similarity values between the particular document or set of documents and other documents based on their respective information types and respective associated weights.