Pratyush Kumar

Our analysis was performed to better understand the relationship between Hb measurement frequency, dose titrations and Hb outcomes. We concluded that frequent Hb monitoring and ESA dose titration may be associated with increased drug utilization
without improved Hb target achievement.

Online systems that help users select the most preferential item from a large electronic catalog are known as product search and recommender systems. Evaluation of various proposed technologies is essential for further development in this area. This paper describes the design and implementation of two user studies in which a particular product search tool, known as example critiquing, was evaluated against a chosen baseline model. The results confirm that example critiquing significantly… Show more

Online systems that help users select the most preferential item from a large electronic catalog are known as product search and recommender systems. Evaluation of various proposed technologies is essential for further development in this area. This paper describes the design and implementation of two user studies in which a particular product search tool, known as example critiquing, was evaluated against a chosen baseline model. The results confirm that example critiquing significantly reduces users' task time and error rate while increasing decision accuracy. Additionally, the results of the second user study show that a particular implementation of example critiquing also made users more confident about their choices. The main contribution is that through these two user studies, an evaluation framework of three criteria was successfully identified, which can be used for evaluating general product search and recommender systems in E-commerce environments. These two experiments and the actual procedures also shed light on some of the most important issues which need to be considered for evaluating such tools, such as the preparation of materials for evaluation, user task design, the context of evaluation, the criteria, the measures and the methodology of result analyses. Show less

A crucial element in consumer electronic commerce is a catalog tool that not only finds the product for the user, but also convinces him that he has made the best choice. To do that, it is important to show him ample choices while keeping his interaction effort below an acceptable limit. Among the various interaction models used in operational e-commerce sites, ranked lists are by far the most popular tool for product navigation and selection. However, as the number of product features and the… Show more

A crucial element in consumer electronic commerce is a catalog tool that not only finds the product for the user, but also convinces him that he has made the best choice. To do that, it is important to show him ample choices while keeping his interaction effort below an acceptable limit. Among the various interaction models used in operational e-commerce sites, ranked lists are by far the most popular tool for product navigation and selection. However, as the number of product features and the complexity of user's criteria increase, a ranked list's efficiency becomes less satisfactory. As an alternative, research groups from the intelligent user interface community have developed various example-based search tools, including SmartClient from our laboratory. These tools not only perform personalized search, but also support tradeoff analysis. However, despite the academic interest, example-based search paradigms have not been widely adopted in practice. We have examined the usability of such tools on a variety of tasks involving selection and tradeoff. The studies clearly show that example-based search is comparable to ranked lists on simple tasks, but significantly reduces the error rate and search time when complex tradeoffs are involved. This shows that such tools are likely to be useful particularly for extending the scope of consumer e-commerce to more complex products. Show less

We describe configuration systems using constraint problem solving formalisms where feasible products are computed by constraint problem solvers. A feasible product is a configuration of constituent components that violates none of the configuration constraints and meets users' preferences as much as possible. To help users find desirable products, a system must possess and understand users' preference model as well as value functions. A constraint-based multi-attribute optimization problem… Show more

We describe configuration systems using constraint problem solving formalisms where feasible products are computed by constraint problem solvers. A feasible product is a configuration of constituent components that violates none of the configuration constraints and meets users' preferences as much as possible. To help users find desirable products, a system must possess and understand users' preference model as well as value functions. A constraint-based multi-attribute optimization problem (MOP) assigns utility functions to the set of feasible configurable products so that optimal ones stand out. Due to the incompleteness and uncertainties of user's preference models, optimal solutions are difficult to compute in practical settings if systems do not constantly interact with users and refine user's preference models. While building four user-involved MOPs, we have accumulated a set of interaction principles that optimize user and system collaboration while computing optimal solutions. In particular, we will concentrate here on our approaches and solutions to address tradeoff tasks in interactive MOPS. Show less