Digital Commons Network^™

A Small-Sample Overlapping Variance-Ratio Test, Yiu Kuen Tse, K. W. Ng, Xibin Zhang

Research Collection School Of Economics

The null distribution of the overlapping variance-ratio (OVR) test of the random-walk hypothesis is known to be downward biased and skewed to the right in small samples. As shown by , the test under-rejects the null on the left tail seriously when the sample size is small. This property adversely affects the applicability of the OVR test to macroeconomic time series, which usually have rather small samples. In this paper, we propose a modified overlapping variance-ratio statistic and derive its exact mean under the normality assumption. We propose to approximate the small-sample distribution of the modified statistic using a beta …

Selection Correction And Sensitivity Analysis For Ordered Treatment Effect On Count Response, Myoung-Jae Lee

Research Collection School Of Economics

In estimating the effect of an ordered treatment [tau] on a count response y with an observational data where [tau] is self-selected (not randomized), observed variables x and unobserved variables [epsilon] can be unbalanced across the control group ([tau] = 0) and the treatment groups ([tau] = 1, . . . , J). While the imbalance in x causes 'overt bias' which can be removed by controlling for x, the imbalance in [epsilon] causes 'covert (hidden or selection) bias' which cannot be easily removed. This paper makes three contributions. First, a proper counter-factual causal framework for ordered treatment effect on …

Market Segmentation And Information Values Of Earnings Announcements: Some Empirical Evidence From An Event Study On The Chinese Stock Market, Y. Gao, Yiu Kuen Tse

Research Collection School Of Economics

This paper investigates the trading activities of two distinct classes of shareholders, namely, the Chinese domestic investors and the foreign investors in the segmented Chinese A- and B-share markets, respectively. We conduct an event study on the annual earnings announcements based on two different accounting standards: International accounting standards (IAS) and PRC generally accepted accounting principles (PRC GAAP). The earnings announcements based on IAS and PRC GAAP are value relevant. The investors in the B-share market react to both the IAS and PRC GAAP earnings announcements, while the investors in the A-share market pay more attention to the PRC GAAP …

Restitution For Mistaken Gifts, Hang Wu Tang

Research Collection Yong Pung How School Of Law

This paper investigates when a donor is entitled to restitution for an executed inter vivos gift made pursuant to a mistake. The causal mistake approach adopted by some leading works is considered, critiqued and rejected as a framework to analyse mistaken gifts. The central thesis of this paper is that a gift is an important transaction which engenders social bonds such as love, affection, intimacy, friendship, trust and gratitude, and these bonds influence the parties’ future conduct in the social sphere. This process has been termed as creating a moral economy. Therefore, just as it is important to protect the …

Strikes Through The Prism Of Duties: Is There A Fundamental Duty To Strike Under The Indian Constitution?, Shubhankar Dam

Research Collection Yong Pung How School Of Law

Much of the debates on the legality of strikes under the Indian Constitution has been on the issue of a right to strike. This paper argues that the constitutionality of strikes may be analysed through the prism of duties, i.e. fundamental duties under Part IVA of the Constitution. Strikes were an integral part of the ideals that inspired India's national struggle against imperialism. And, in this sense, when article 51A exhorts Indians to cherish and follow the noble ideals that inspired our freedom struggle, it includes a fundamental duty to strike. Invoking the philosophy of Mahatma Gandhi, the paper argues …

Peoples Union For Civil Liberties V Union Of India: Is Indian Democracy Dependent On A Statute?, Shubhankar Dam

Research Collection Yong Pung How School Of Law

What is the status of a right to vote in the Indian legal system? Is the right a constitutional/fundamental right? Or is it simply a statutory right? Contrary to the decisions of the Supreme Court in the last five decades, this paper argues that the right to vote is a constitutional right: its textual foundation may be located in Article 326. And, in this sense, the Supreme Court has erred in construing the right to vote as a statutory right under the Representation of Peoples Act, 1951. Interpreting the right to vote as a statutory right has larger implications for …

Paper For An Educational Digital Library, Dion Hoe-Lian Goh, Yin-Leng Theng, Ming Yin, Ee Peng Lim

Research Collection School Of Computing and Information Systems

GeogDL is a digital library of geography examination resources designed to assist students in revising for a national geography examination in Singapore. As part of an iterative design process, we carried out participatory design and brainstorming with student and teacher design partners. The first study involved prospective student design partners. In response to the first study, we describe in this paper an implementation of PAPER – Personalised Adaptive Pathways for Exam Resources – a new bundle of personalized, interactive services containing a mock exam and a personal coach. The mock exam provides a simulation of the actual geography examination while …

The Eu And The Non-Proliferation Of Nuclear Weapons: The Way To Thessaloniki And Beyond, Clara Portela

Research Collection School of Social Sciences

This paper discusses EU policies against the proliferation of weapons of mass destruction (WMD). The author states that at the beginning of the century, the EU began taking steps against the spread of nuclear weapons within its Common Foreign and Security Policy (CFSP). In June 2003, the European Council adopted its first draft strategy against the proliferation of WMDs. In order to assess the significance of the strategy, the paper presents and evaluates the Union’s record in the field, reviews the strategy and makes suggestions as to how it can be improved.

Structuring Lecture Videos For Distance Learning Applications, Chong-Wah Ngo, Feng Wang, Ting-Chuen Pong

Research Collection School Of Computing and Information Systems

This paper presents an automatic and novel approach in structuring and indexing lecture videos for distance learning applications. By structuring video content, we can support both topic indexing and semantic querying of multimedia documents. In this paper, our aim is to link the discussion topics extracted from the electronic slides with their associated video and audio segments. Two major techniques in our proposed approach include video text analysis and speech recognition. Initially, a video is partitioned into shots based on slide transitions. For each shot, the embedded video texts are detected, reconstructed and segmented as high-resolution foreground texts for commercial …

How Are Social Identities Linked To Self-Conception And Intergroup Orientation? The Moderating Effect Of Implicit Theories, Ying-Yi Hong, Gloria Chan, Chi-Yue Chiu, Rosanna Y. M. Wong, Ian G. Hansen, Sau-Lai Lee, Jennifer Yuk-Yue Tong, Ho-Ying Fu

Research Collection School of Social Sciences

Social identity approaches assume that social identification affects both self-conception and intergroup orientation. The authors contend that such social identification effects are accentuated when people hold a fixed view of human character and attribute immutable dispositions to social groups. To these individuals, social identities are immutable, concrete entities capable of guiding self-conception and intergroup orientation. Social identification effects are attenuated when people hold a malleable view of human character and thus do not view social identities as fixed, concrete entities. The authors tested and found support for this contention in three studies that were conducted in the context of the …

Xstamps: A Multiversion Timestamps Concurrency Control Protocol For Xml Data, Khin-Myo Win, Wee-Keong Ng, Ee Peng Lim

Research Collection School Of Computing and Information Systems

With the tremendous growth of XML data over the Web, efficient management of such data becomes a new challenge for database community. Several data management solutions, proposed in recent years, extend the capability of traditional database systems to meet the needs of XML data while alternative approaches introduce new generation databases, named as native XML database management systems. Although traditional databases have mature transaction management and concurrency control techniques, there is still a need to tailor techniques for native XML databases in order to deal with distinct characteristics of XML. In this paper, we propose XStamps, a multiversion timestamps concurrency …

The Structure Of Affect: Reconsidering The Relationship Between Negative And Positive Affectivity, Russell Cropanzano, Howard M. Weiss, Jeff M. S. Hale, Jochen Reb

Research Collection Lee Kong Chian School Of Business

During the past decade organizational scientists have devoted considerable research attention to the topic of workplace affect. Despite important advances, continued progress depends on a better understanding of the structure of affective experience. The goal of this paper is to review progress to date. In particular, we review evidence pertaining to four constructs that have been widely used to organize research on affect: positive affectivity, negative affectivity, hedonic tone, and affect intensity. We review various structural models pertaining to these four constructs, devoting special attention to integrative frameworks and future research needs. Corresponding au

An Investigation Of Consumer Online Trust And Purchase-Repurchase Intentions, Dan J. Kim, Donald Ferrin, Raghav Rao

Research Collection Lee Kong Chian School Of Business

There is little research on trust and satisfaction in the electronic commerce from a longitudinal (pre- and postpurchase) perspective. Based on previous frameworks and theories, this study developed a combined model of consumer trust and satisfaction in the context of Internet shopping. From the valance framework and expectation-confirmation theory, several prepurchase and post-purchase factors such as risk, benefit, consumer trust, expectation, confirmation, and satisfaction are investigated as research variables affecting consumer repurchase intention.

The results of the study show that trust is the strongest predictor of the consumer’s purchase intention. In addition, as in traditional consumer satisfaction studies, it holds …

Modularity And The Product Lifecycle, Peter Cebon, Oscar Hauptman, Chander Shekhar

Research Collection Lee Kong Chian School Of Business

Product lifecycle theory, which underlies theories of technical innovation in economics, strategy, marketing, and operations management, is based implicitly on the assumption that products are integrated wholes. The modularization of products undermines the specific synergies which drive the product lifecycle, and this undermining has impacts spanning from the structure of individual organizations to the structure of economies and the definition of industries.

The Arms Trade In Russian-Chinese Relations: Identity, Domestic Politics, And Geopolitical Positioning, Robert H. Donaldson, John A. Donaldson

Research Collection School of Social Sciences

Why would a declining power help arm a neighboring and once-hostile rising power? Current international relations literature cannot explain relationships in which one powerful country contributes directly to its long-term relative decline in order to make smaller, short-term gains. This study focuses on one example, the Treaty on Good Neighborly Friendship and Cooperation between the Russian Federation and the People's Republic of China, signed in Moscow on July 16, 2001. Presenting evidence that this alliance embodies a relationship that is based primarily on sales of arms from Russia to China, the authors argue that this association cannot be explained by …

Moorean Absurdity, Knowledge And Iterated Belief, John N. Williams

Research Collection School of Social Sciences

No abstract provided.

Creating A Virtual Store Image, P. Katerattanakul, Keng Siau

Research Collection School Of Computing and Information Systems

A study was conducted to describe some of the factors that needed to be considered for a virtual store. It was revealed that the growth of e-commerce and online businesses has made it essential to understand the critical attributes of image for a virtual store. Store image was described as the way in which the store was defined by customers and several studies. The study compiled 77 designs and features into a list used to construct a survey. Four hundred and twenty-seven potential customers were requested to rate the significance of each item on the list. The information gathered identified …

Score Tests For Inverse Gaussian Mixture, Zhenlin Yang

Research Collection School Of Economics

The mixed inverse Gaussian given by Whitmore (Scand. J. Statist., 13, 1986, 211–220) provides a convenient way for testing the goodness-of-fit of a pure inverse Gaussian distribution. The test is a one-sided score test with the null hypothesis being the pure inverse Gaussian (i.e. the mixing parameter is zero) and the alternative a mixture. We devise a simple score test and study its finite sample properties. Monte Carlo results show that it compares favourably with the smooth test of Ducharme (Test, 10, 2001, 271-290). In practical applications, when the pure inverse Gaussian distribution is rejected, one is interested in making …

Information Recovery In A Study With Surrogate Endpoints, Song Xi Chen, Denis H. Y. Leung, Jing Qin

Research Collection School Of Economics

Recently, there has been a lot of interest in statistical methods for analyzing data with surrogate endpoints. In this article, we consider parameter estimation from a model that relates a variable Y to a set of covariates, X, in the presence of a surrogate, S. We assume that the data are made up of two random samples from the population, a validation set where (Y, X, S) are observed on every subject and a nonvalidation set where only (X, S) are measured. We show how information from the nonvalidation set can be incorporated to improve upon estimation of a parameter …

Optimum Currency Area In Europe: An Alternative Evaluation, Yoonbai Kim, Hwee Kwan Chow

Research Collection School Of Economics

In this paper we explore an alternative scheme to assess the suitability of adopting a common currency by Western European countries. It is based on the role of common regional shocks in the determination of output. The results show that the OCA theory well explains and predicts participation decisions in EMU. We also find that our OCA index is highly consistent with two popular schemes that have been introduced by Bayoumi and Eichengreen.

The Impacts Of Hong Kong's Currency Board Reforms On Its Interbank Market, Yiu Kuen Tse, Paul S. L. Yip

Research Collection School Of Economics

Among the economies with a Currency Board System (CBS), Hong Kong (HK) is probably the one with the largest and most developed financial sector, as well as the highest capital mobility. Hence, studying HK’s CBS is not only crucial to HK, but also important for the understanding of the modern CBS. This paper outlines the major monetary reforms in HK since the late 1980s. The impacts of these reforms and the 1997–1998 Asian Financial Crisis are then examined empirically. We focus on the differentials between the US and HK interbank interest rates. We assume the conditional-mean equation follows an autoregressive …

Fiducial Predictive Densities And Econometric Duration Analysis, Zhenlin Yang

Research Collection School Of Economics

In this article, we propose using fiducial predictive density (FPD) as a density estimate, which leads naturally to estimators of survivor and hazard functions and provides a simple way of constructing shortest prediction intervals. This approach is studied in detail in the context of two flexible duration models proposed in this paper, namely the trans-normal and trans-exponential families, by presenting the FPDs, their basic properties, their Bayesian correspondence and their applications in econometric duration analysis. Empirical evidences show that the FPD method provides better estimates of survivor and hazard functions, particularly the latter, than does the usual maximum likelihood method. …

Aa Flexible And Scalable Authentication Scheme For Jpeg 2000 Image Codestreams, Cheng Peng, Robert H. Deng, Yongdong Wu, Weizhong Shao

Research Collection School Of Computing and Information Systems

JPEG2000 is an emerging standard for still image compression and is becoming the solution of choice for many digital imaging fields and applications. An important aspect of JPEG2000 is its "compress once, decompress many ways" property [1], i. e., it allows extraction of various sub-images (e.g., images with various resolutions, pixel fidelities, tiles and components) all from a single compressed image codestream. In this paper, we present a flexible and scalable authentication scheme for JPEG2000 images based on the Merkle hash tree and digital signature. Our scheme is fully compatible with JPEG2000 and possesses a "sign once, verify many ways" …

Content-Aware Authentication Of Motion Jpeg2000 Stream In Lossy Networks, Yongdong Wu, Robert H. Deng

Research Collection School Of Computing and Information Systems

Stream authentication schemes (SAS) aim to achieve effective authentication of multicast streams over lossy networks. Almost all the existing SASs is designed for stream data integrity protection only. In this paper, we argue that content integrity protection is more important than data integrity to human users. We present a content-aware SAS in motion JPEG2000 streaming. In our scheme, a chunk of JPEG2000 codestreams is encapsulated into a block of packets using multiple description coding (MDC). Our MDC exploits the inherent structure of motion JPEG2000 codestreams and is used to preserve the semanteme/content of the stream over lossy networks. To achieve …

Web Unit Mining: Finding And Classifying Subgraphs Of Web Pages, Aixin Sun, Ee Peng Lim

Research Collection School Of Computing and Information Systems

In web classification, most researchers assume that the objects to classify are individual web pages from one or more web sites. In practice, the assumption is too restrictive since a web page itself may not always correspond to a concept instance of some semantic concept (or category) given to the classification task. In this paper, we want to relax this assumption and allow a concept instance to be represented by a subgraph of web pages or a set of web pages. We identify several new issues to be addressed when the assumption is removed, and formulate the web unit mining …

A Robust Dissolve Detector By Support Vector Machine, Chong-Wah Ngo

Research Collection School Of Computing and Information Systems

In this paper, we propose a novel approach for the robust detection and classification of dissolve sequences in videos. Our approach is based on the multi-resolution representation of temporal slices extracted from 3D image volume. At the low-resolution (LR) scale, the problem of dissolve detection is reduced as cut transition detection. At the highresolution (HR) space, Gabor wavelet features are computed for regions that surround the cuts located at LR scale. The computed features are then input to support vector machines for pattern classification. Encouraging results have been obtained through experiments.

Tests Of Functional Form And Heteroscedasticity, Zhenlin Yang, Yiu Kuen Tse

Research Collection School Of Economics

This paper considers tests of misspecification in a heteroscedastic transformation model. We derive Lagrange multiplier (LM) statistics for (i) testing functional form and heteroscedasticity jointly, (ii) testing functional form in the presence of heteroscedasticity, and (iii) testing heteroscedasticity in the presence of data transformation. We present LM statistics based on the expected information matrix. For cases (i) and (ii), this is done assuming the Box-Cox transformation. For case (iii), the test does not depend on whether the functional form is estimated or pre-specified. Small-sample properties of the tests are assessed by Monte Carlo simulation, and comparisons are made with the …

Synchronization Of Lecture Videos And Electronic Slides By Video Text Analysis, Feng Wang, Chong-Wah Ngo, Ting-Chuen Pong

Research Collection School Of Computing and Information Systems

An essential goal of structuring lecture videos captured in live presentation is to provide a synchronized view of video clips and electronic slides. This paper presents an automatic approach to match video clips and slides based on the analysis of text embedded in lecture videos. We describe a method to reconstruct high-resolution video texts from multiple keyframes for robust OCRrecognition. A two-stage matching algorithm based on the title and content similarity measures between video clips and slides is also proposed.

Validating Digital Signatures Without Ttp’S Time-Stamping And Certificate Revocation, Jianying Zhou, Feng Bao, Robert H. Deng

Research Collection School Of Computing and Information Systems

In non-repudiation services where digital signatures usually serve as irrefutable cryptographic evidence for dispute resolution, trusted time-stamping and certificate revocation services, although very costly in practice, must be available, to prevent big loss due to compromising of the signing key. In [12], a new concept called intrusion-resilient signature was proposed to get rid of trusted time-stamping and certificate revocation services and a concrete scheme was presented. In this paper, we put forward a new scheme that can achieve the same effect in a much more efficient way. In our scheme, forward-secure signature serves as a building block that enables signature …

Automatic Video Summarization By Graph Modeling, Chong-Wah Ngo, Yu-Fei Ma, Hong-Jiang Zhang

Research Collection School Of Computing and Information Systems

We propose a unified approach for summarization based on the analysis of video structures and video highlights. Our approach emphasizes both the content balance and perceptual quality of a summary. Normalized cut algorithm is employed to globally and optimally partition a video into clusters. A motion attention model based on human perception is employed to compute the perceptual quality of shots and clusters. The clusters, together with the computed attention values, form a temporal graph similar to Markov chain that inherently describes the evolution and perceptual importance of video clusters. In our application, the flow of a temporal graph is …