A novel latent factor model for recommender system

Matrix factorization (MF) has evolved as one of the better practice to handle sparse data in field of recommender systems. Funk singular value decomposition (SVD) is a variant of MF that exists as state-of-the-art method that enabled winning the Netflix prize competition. The method is widely used with modifications in present day research in field of recommender systems. With the potential of data points to grow at very high velocity, it is prudent to devise newer methods that can handle such data accurately as well as efficiently than Funk-SVD in the context of recommender system. In view of the growing data points, I propose a latent factor model that caters to both accuracy and efficiency by reducing the number of latent features of either users or items making it less complex than Funk-SVD, where latent features of both users and items are equal and often larger. A comprehensive empirical evaluation of accuracy on two publicly available, amazon and ml-100 k datasets reveals the comparable accuracy and lesser complexity of proposed methods than Funk-SVD.

CATEGORIZATION OF BRAZILIAN INTERNET USERS AND ITS IMPACTS ON THE USE OF ELECTRONIC GOVERNMENT SERVICES

This paper aims to categorize Brazilian Internet users according to the diversity of their online activities and to assess the propensity of these Internet users´ groups to use electronic government (e-gov) services. The Amartya Sen’s Capability Approach was adopted as the theoretical framework for its consideration of people’s freedom to decide on their use of available resources and their competencies for these decisions, leading to the use of e-gov services. Multivariate statistical techniques were used to perform data analysis from the 2007, 2009 and 2011 editions of ICT Household Survey. The results showed that Internet users belonging to the advanced and intermediate use groups were more likely to use e-gov services than those who belong to the sporadic use group. Moreover, the results also demonstrated that the Internet user group of intermediate use presented a higher tendency to use e-gov services than the Internet user group of advanced use. This tendency is possibly related to the extensive use of interactive and collaborative activities of leisure and entertainment performed by this type of user. The findings of this research may be useful in guiding public policies for the dissemination and provision of electronic government services in Brazil.