Web Intelligence & Recommender Systems

I have been working on producing intelligent information retrieval methods that can pro-actively cater to the changing demands of user communities. Classic information retrieval algorithms did not effectively use the implicit knowledge accumulated from usage patterns. In other words, information retrieval used to rely exclusively on users "pulling" the information they needed from a passive environment. More recently, much effort has been posited on developing a different paradigm for information retrieval which relies much more on computational environments that "push" relevant information to users according to previous patterns of information retrieval. This kind of information retrieval has been described as Active Collaborative Filtering, Knowledge Mining, and even Knowledge Self-Organization in distributed information systems (DIS).

I have been developing active recommendation systems for DIS based on adaptive environments which are both collaborative and content-based, as they integrate information from the patterns of usage of groups of users and also categorize database content or semantics in a manner relevant to those groups. One of these systems, TalkMine, further allows the (adaptive) transmission of information across databases, as users may search several databases at the same time. TalkMine entails an open-ended human-machine symbiosis, which can be used in the automatic, adaptive, organization of knowledge in DIS such as library databases or the Internet, facilitating the rapid dissemination of relevant information and the discovery of new knowledge. TalkMine is based on several bio-inspired mechanisms: cognitive categorization as modeled by Fuzzy Set Theory and Dempster-Shafer Theory of Evidence, a connectionist memory architecture, and Hebbian learning for adaptive memory organization.

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Network of 1300 journal titles accessed by the users of the MyLibrary Web Service at the Los Alamos National Laboratory

The links shown denote a strong measure of co-occurrence (proximity) of two journals (the nodes) in user personalities. From this network, two main clusters were identified via Singular Value Decomposition: one pertaining to journals in chemistry, materials science, physics and the other to computer science and applied mathematics. A smaller cluster pertaining to journals in bioinformatics and computational biology is also highlighted. Figure better described in a recent paper describing our network approach to recommendation systems.

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Web interface of the recommendation system in the MyLibrary@LANL Web Service

Figure shows journals being recommended for the "Cognitive Science" personality of a user. This system is better described in a recent paper describing our network approach to recommendation systems.

The recommendation systems I have been investigating aim at the creation of adaptive knowledge networks that facilitate collaboration among individuals, each with various search personalities. Indeed, I have been particularly interested in collaborative systems that are also strong on personalization---preserving distinct search personalities for each user. The systems we have developed aim at the open-ended self-organization and adaptation of DIS to the particular, diverse needs of their users. We refer to these systems as Adaptive Webs. The TalkMine system, in particular, was originally developed for the library without walls project of the Los Alamos National Laboratory research library. A testbed for TalkMine was development under the Active Recommendation Project. Other recommendation systems based on network models have been developed and are currently implemented in the MyLibrary Web Service at Los Alamos. The figure above depicts an associative network of more than a thousand journal titles accessed by the users of MyLibrary, where the links denote strong co-occurrence associations. The figure below depicts the web interface of this service.

Funding Project partially funded by




Project Members

Luis Rocha

Johan Bollen

Tiago Simas

Rion Brattig Correia




Selected Project Publications