Efficient Processing of k Nearest Neighbor Joins using MapReduce

k nearest neighbor join (kNN join), designed to find k nearest neighbors from a dataset S for every object in another dataset R, is a primitive operation widely adopted by many data mining applications. As a combination of the k nearest neighbor query and the join operation, kNN join is an expensive operation. Given the increasing volume of data, it is difficult to perform a kNN join on a centralized machine efficiently. In this paper, we investigate how to perform kNN join using MapReduce which is a well-accepted framework for data-intensive applications over clusters of computers. In brief, the mappers cluster objects into groups; the reducers perform the kNN join on each group of objects separately. We design an effective mapping mechanism that exploits pruning rules for distance filtering, and hence reduces both the shuffling and computational costs. To reduce the shuffling cost, we propose two approximate algorithms to minimize the number of replicas. Extensive experiments on our in-house cluster demonstrate that our proposed methods are efficient, robust and scalable.Comment: VLDB201

PeerDB-Peering into Personal Databases

In this talk, we will present the design and evaluation of PeerDB, a peer-to-peer (P2P) distributed data sharing system. PeerDB distinguishes itself from existing P2P systems in several ways. First, it is a full-fledge data management system that supports fine-grain content-based searching. Second, it facilitates sharing of data without shared schema. Third, it combines the power of mobile agents into P2P systems to perform operations at peers' sites. Fourth, PeerDB network is self-configurable, i.e., a node can dynamically optimize the set of peers that it can communicate directly with based on some optimization criterion.Singapore-MIT Alliance (SMA

An Exploratory Study Of Brand Equity And Malaysian Consumer Purchase Intention Towards Hotel Accommodation

Hotel accommodation are one of the important services sector that contribute to the growth of Malaysian GDP and facing challenges with the rapid changes in economic, social, political, demographic, competition, technological and others that led to consumer behavior changes. In this globalization environment, hoteliers facing stiff competition to attract more visitors for both local and foreign travelers with their limited resources. To stay sustainability, brand equity plays an important role for marketer on market positioning. Thus, Aaker’s Brand Equity Model is adopted in this study to examine the impact of brand awareness, brand loyalty, brand associations, perceived quality and brand image as independent variable to brand equity and the influence of brand equity on Malaysian consumer purchase intention towards hotel accommodations

Effectiveness of sales manager's leadership in implementing lead management: A case study on Tan Chong Motors (Sarawak)

The mission of Tan Chong Motors (TCM) Sarawak was to fulfill top management’s vision for Sarawak Region Mid-Term Plan of increasing the current market share of 3.6% (for year 2011) to 24.4% by 2016. The sales management and leadership behaviors of present Heads of Branch (HOBs) were found to be ineffective, especially in managing and leading the sales teams to achieve the mid-term goal by Year 2016. The aim of this research was to examine factors influencing HOBs’ leadership in implementing lead management in Tan Chong Motors (TCM) Sarawak region. Hence, the major focus of this study was to examine the effectiveness of HOBs’ leadership behaviors and sales management approaches in the branch sales operation in Sarawak Region. For this purpose, an action research (AR) embedded within the conceptual framework was conducted in three cycles involving; formative evaluation, application and implementation of change by Tan Chong Motors Sarawak Region and TCM Head Quarter (HQ). Process, impact and outcome evaluation data was obtained from quantitative and a combination of qualitative approaches namely; structured interviews, participant’s observations, archival search, focus group discussion and critical incident technique. The participants of this study were HOBs of the five branches in TCM Sarawak Region. Survey was also conducted on 62 sales advisors from the respective branch. The study found that inadequacy of leadership behaviors and lack of management knowledge, lack of structured management control processes, lack of clear job scope and an inefficient Lead Management Information System were the main reasons contributing to the leadership ineffectiveness in implementation lead management in TCM Sarawak Region. With the findings of this AR, TCM HQ has adopted and standardized the four proposals made, namely to adopt farming approach of selling, to enhance Lead Management Information System, to standardize HOBs’ job scope and, to provide structured training program for all TCM HOB

Efficient Spatial Keyword Search in Trajectory Databases

An increasing amount of trajectory data is being annotated with text descriptions to better capture the semantics associated with locations. The fusion of spatial locations and text descriptions in trajectories engenders a new type of top-$k$ queries that take into account both aspects. Each trajectory in consideration consists of a sequence of geo-spatial locations associated with text descriptions. Given a user location $\lambda$ and a keyword set $\psi$, a top-$k$ query returns $k$ trajectories whose text descriptions cover the keywords $\psi$ and that have the shortest match distance. To the best of our knowledge, previous research on querying trajectory databases has focused on trajectory data without any text description, and no existing work has studied such kind of top-$k$ queries on trajectories. This paper proposes one novel method for efficiently computing top-$k$ trajectories. The method is developed based on a new hybrid index, cell-keyword conscious B$^+$-tree, denoted by \cellbtree, which enables us to exploit both text relevance and location proximity to facilitate efficient and effective query processing. The results of our extensive empirical studies with an implementation of the proposed algorithms on BerkeleyDB demonstrate that our proposed methods are capable of achieving excellent performance and good scalability.Comment: 12 page

Collaborative Data Publishing and Searching System

In this paper, we present a folksonomy-based collaborative data publishing and searching system. The system accepts data objects described with user-created metadata, called data units. The system supports flexible structure on the data units, and places no restrictions on the vocabulary used. We devise a generic table model for storing and representing the data units of various structures. We propose a framework for managing the data units and providing browsing, searching and querying services over them. We present our current approaches and discuss relevant research issues.Singapore-MIT Alliance (SMA