Facilitating interaction and retrieval for annotated documents

Digital annotation of web pages presents new problems connected to the dynamics and the openness of the web. First, the variety of available browsers may require the use of proprietary solutions, once one goes beyond traditional interaction with hyperlinks. Second, documents are replicated over multiple sites and can be retrieved at different URLs or with different queries. Hence, annotations on a web content must be retrieved even if they were created while accessing the same content under a different URL. Moreover, when pages are modified, annotations related to fragments that have moved within the page itself should be retrieved and shown to the user. We have improved the MADCOW annotation system with a uniform interaction paradigm and incorporated two algorithms: one to assess the identity of two pages under two different URLs and the other to identify variations in two versions of a page under the same URL. Copyright © 2010 Inderscience Enterprises Ltd.