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True Believers Or Moral Absolutists, Seow Hon Tan Nov 2004

True Believers Or Moral Absolutists, Seow Hon Tan

Research Collection Yong Pung How School Of Law

The recent American presidential elections brought to the fore the question of what place moral values have in public decision-making when traditional moral values are not espoused by all in a pluralist society. Even if traditional values - seen as absolutist - are imposed on others through a democratic electoral process, that imposition, particularly in hot button issues like abortion and same-sex marriage, remains difficult to accept.

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Pre-Crime, Pre-Punishment And Pre-Desert, John N. Williams Nov 2004

Pre-Crime, Pre-Punishment And Pre-Desert, John N. Williams

Research Collection School of Social Sciences

No abstract provided.

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The Changing Political Economy Of Party Membership, Riccardo Pelizzo Nov 2004

The Changing Political Economy Of Party Membership, Riccardo Pelizzo

Research Collection School of Social Sciences

Although few scholars would dispute from an empirical point of view the fact that parties change their electoral strategies, ideological stances and organizational structures over time, there is not much agreement on how these changes, above all party organizational change, have to be understood from a theoretical point of view. This is especially true with regard to the transformations that party organizations have undergone from the early 1970s on. In fact, although party organizational changes in the past three decades have generally been considered to be signs of the so called party crisis, the agreement on this analytical perspective is …

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Multivariate Stochastic Volatility Models: Bayesian Estimation And Model Comparison, Jun Yu, Renate Meyer Nov 2004

Multivariate Stochastic Volatility Models: Bayesian Estimation And Model Comparison, Jun Yu, Renate Meyer

Research Collection School Of Economics

In this paper we show that fully likelihood-based estimation and comparison of multivariate stochastic volatility (SV) models can be easily performed via a freely available Bayesian software called WinBUGS. Moreover, we introduce to the literature several new specifications which are natural extensions to certain existing models, one of which allows for time varying correlation coefficients. Ideas are illustrated by fitting, to a bivariate time series data of weekly exchange rates, nine multivariate SV models, including the specifications with Granger causality in volatility, time varying correlations, heavy-tailed error distributions, additive factor structure, and multiplicative factor structure. Empirical results suggest that the …

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Asymmetric Response Of Volatility: Evidence From Stochastic Volatility Models And Realized Volatility, Jun Yu Nov 2004

Asymmetric Response Of Volatility: Evidence From Stochastic Volatility Models And Realized Volatility, Jun Yu

Research Collection School Of Economics

This paper examines the asymmetric response of equity volatility to return shocks. We generalize the news impact function (NIF), originally introduced by Engle and Ng (1993) to study asymmetric volatility under the ARCH-type models, to be applicable to both stochastic volatility (SV) and ARCH-type models. Based on the generalized concept, we provide a unified framework to examine asymmetric properties of volatility. A new asymmetric volatility model, which nests both ARCH and SV models and at the same time allows for a more flexible NIF, is proposed. Empirical results based on daily index return data support the classical asymmetric SV model …

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On Semantic Caching And Query Scheduling For Mobile Nearest-Neighbor Search, Baihua Zheng, Wang-Chien Lee, Dik Lun Lee Nov 2004

On Semantic Caching And Query Scheduling For Mobile Nearest-Neighbor Search, Baihua Zheng, Wang-Chien Lee, Dik Lun Lee

Research Collection School Of Computing and Information Systems

Location-based services have received increasing attention in recent years. In this paper, we address the performance issues of mobile nearest-neighbor search, in which the mobile user issues a query to retrieve stationary service objects nearest to him/her. An index based on Voronoi Diagram is used in the server to support such a search, while a semantic cache is proposed to enhance the access efficiency of the service. Cache replacement policies tailored for the proposed semantic cache are examined. Moreover, several query scheduling policies are proposed to address the inter-cell roaming issues in multi-cell environments. Simulations are conducted to evaluate the …

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The D-Tree: An Index Structure For Planar Point Queries Location-Based Wireless Services, Jianliang Xu, Baihua Zheng, Wang-Chien Lee, Dik Lun Lee Nov 2004

The D-Tree: An Index Structure For Planar Point Queries Location-Based Wireless Services, Jianliang Xu, Baihua Zheng, Wang-Chien Lee, Dik Lun Lee

Research Collection School Of Computing and Information Systems

Location-based services (LBSs), considered as a killer application in the wireless data market, provide information based on locations specified in the queries. In this paper, we examine the indexing issue for querying location-dependent data in wireless LBSs; in particular, we focus on an important class of queries, planar point queries. To address the issues of responsiveness, energy consumption, and bandwidth contention in wireless communications, an index has to minimize the search time and maintain a small storage overhead. It is shown that the traditional point-location algorithms and spatial index structures fail to achieve either objective or both. This paper proposes …

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Moore's Paradoxes, Evans's Principle And Self-Knowledge, John N. Williams Oct 2004

Moore's Paradoxes, Evans's Principle And Self-Knowledge, John N. Williams

Research Collection School of Social Sciences

I supply an argument for Evans’s principle that whatever justifies me in believing that p also justifies me in believing that I believe that p. I show how this principle helps explain how I come to know my own beliefs in a way that normally makes me the best authority on them. Then I show how the principle helps to solve Moore’s paradoxes.

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Structuring Home Video By Snippet Detection And Pattern Parsing, Zailiang Pan, Chong-Wah Ngo Oct 2004

Structuring Home Video By Snippet Detection And Pattern Parsing, Zailiang Pan, Chong-Wah Ngo

Research Collection School Of Computing and Information Systems

Hand-held camcorders have been popularly used in capturing and documenting daily lives. Nonetheless, searching for personal memories in home videos is still a laborious task. This paper describes novel approaches in detecting snippets and patterns in home videos for content indexing. To deal with the fact that most shots are long and with handshake artifacts, a motion analysis algorithm based on Kalman filter and finite state machine is proposed to decompose videos into tables of snippets. Each snippet is represented by a set of moving and static patterns. The moving patterns are automatically detected and tracked, while the static patterns …

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Clip-Based Similarity Measure For Hierarchical Video Retrieval, Yuxin Peng, Chong-Wah Ngo Oct 2004

Clip-Based Similarity Measure For Hierarchical Video Retrieval, Yuxin Peng, Chong-Wah Ngo

Research Collection School Of Computing and Information Systems

This paper proposes a new approach and algorithm for the similarity measure of video clips. The similarity is mainly based on two bipartite graph matching algorithms: maximum matching (MM) and optimal matching (OM). MM is able to rapidly filter irrelevant video clips, while OM is capable of ranking the similarity of clips according to the visual and granularity factors. Based on MM and OM, a hierarchical video retrieval framework is constructed for the approximate matching of video clips. To allow the matching between a query and a long video, an online clip segmentation algorithm is also proposed to rapidly locate …

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Comments On "A Practical (T, N) Threshold Proxy Signature Scheme Based On The Rsa Cryptosystem", Guilin Wang, Feng Bao, Jianying Zhou, Robert H. Deng Oct 2004

Comments On "A Practical (T, N) Threshold Proxy Signature Scheme Based On The Rsa Cryptosystem", Guilin Wang, Feng Bao, Jianying Zhou, Robert H. Deng

Research Collection School Of Computing and Information Systems

In a (t, n) threshold proxy signature scheme based on RSA, any t or more proxy signers can cooperatively generate a proxy signature while t-1 or fewer of them can't do it. The threshold proxy signature scheme uses the RSA cryptosystem to generate the private and the public key of the signers. In this article, we discuss the implementation and comparison of some threshold proxy signature schemes that are based on the RSA cryptosystem. Comparison is done on the basis of time complexity, space complexity and communication overhead. We compare the performance of four schemes: Hwang et al., Wen et …

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Legislative Ethics And Codes Of Conduct, Rick Stapenhurst, Riccardo Pelizzo Oct 2004

Legislative Ethics And Codes Of Conduct, Rick Stapenhurst, Riccardo Pelizzo

Research Collection School of Social Sciences

The purpose of this paper is to discuss why and how ethics reforms have been enacted by many parliaments in the course of the past decade. Our argument is fairly straightforward. Politicians’ perceived irresponsiveness, various forms of misconduct and corruption scandals have eroded voters’ trust in politicians and political institutions. In order to induce a more ethical behavior among politicians as well as to rebuild public trust in political institutions, ethics regimes have been adopted by several legislatures. Such regimes have generally taken two main forms: ethics codes and conduct codes. Ethics codes tend to be fairly general documents: they …

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Informal Animation Sketching: Requirements And Design, Richard C. Davis, James A. Landay Oct 2004

Informal Animation Sketching: Requirements And Design, Richard C. Davis, James A. Landay

Research Collection School Of Computing and Information Systems

We present an interface design for creating informal animations from sketches. Current tools for creating animation are extremely complex. This makes it difficult for designers to prototype animations and nearly impossible for novices to create them at all. Simple animation systems exist but severely restrict the types of motion that can be represented. To guide our design of an animation sketching interface, we conducted field studies into the needs of professional and novice animators. These studies show the wide variety of motions that users desire in informal animations and indicate how to prioritize these types of otion. The interface described …

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The Contribution Of A Satellite Market To Price Discovery: Evidence From The Singapore Exchange, Vicentiu Covrig, David K. Ding, Buen Sin Low Oct 2004

The Contribution Of A Satellite Market To Price Discovery: Evidence From The Singapore Exchange, Vicentiu Covrig, David K. Ding, Buen Sin Low

Research Collection Lee Kong Chian School Of Business

The Singapore Exchange (SGX), a small satellite market, successfully competes with a large home market, the Osaka Securities Exchange (OSE), in trading the Nikkei 225 futures index. In this paper, we investigate the contribution of the SGX to price discovery and shed light on the reasons for its continued success. Evidence is provided from information revelation and price discovery of three competing but informationally linked markets of the Nikkei 225 index - domestic spot (Tokyo Stock Exchange), domestic futures (OSE), and foreign futures (SGX), which represents the satellite market. Overall, the futures market contributes 77% to price discovery, with the …

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Prospect Theory, Analyst Forecast, And Stock Returns, David K. Ding, Charlie Charoenwong, Raymond Seetoh Oct 2004

Prospect Theory, Analyst Forecast, And Stock Returns, David K. Ding, Charlie Charoenwong, Raymond Seetoh

Research Collection Lee Kong Chian School Of Business

This paper documents how prospect theory can be used to explain stock returns and analysts' forecast behavior. Positive earnings surprises are associated with increases in abnormal returns but negative earnings surprises have only a limited negative impact on returns. We find that analysts display asymmetric behavior towards positive and negative earnings growth. Analysts' forecasts are found to be accurate during periods of positive earnings growth, but overly optimistic during periods of negative earnings growth. Our findings have implications for the structuring of investment products, as well as the role of market timing in their introduction.

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Investing In Hedge Funds: Risks, Returns And Performance Measurement, Francis Koh, Winston T. H. Koh, David K. C. Lee, Kok Fai Phoon Oct 2004

Investing In Hedge Funds: Risks, Returns And Performance Measurement, Francis Koh, Winston T. H. Koh, David K. C. Lee, Kok Fai Phoon

Research Collection Lee Kong Chian School Of Business

Hedge funds are collective investment vehicles that are often established with a special legal status that allows their investment managers a free hand to use derivatives, short sell, and exploit leverage to raise returns and cushion risk. We review various issues relating to the investment in hedge funds, which have become popular with high net-worth individuals and institutional investors, as well as discuss their empirical risk and return profiles. The concerns regarding the empirical measurements are highlighted, and meaningful analytical methods are proposed to provide greater risk transparency in performance reporting. We also discuss the development of the hedge fund …

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Chaos-Induced Escape Over A Potential Barrier, L. Y. Chew, Hian Ann, Christopher Ting, C. H. Lai Oct 2004

Chaos-Induced Escape Over A Potential Barrier, L. Y. Chew, Hian Ann, Christopher Ting, C. H. Lai

Research Collection Lee Kong Chian School Of Business

We investigate the statistical parity of a class of chaos-generated noises on the escape of strongly damped particles out of a potential well. We show that statistical asymmetry in the chaotic fluctuations can lead to a skewed Maxwell–Boltzmann distribution in the well. Depending on the direction of skew, the Kramers escape rate is enhanced or suppressed accordingly. Based on the Perron–Frobenious equation, we determine an analytical expression for the escape rate’s prefactor that accounts for this effect. Furthermore, our perturbative analysis proves that in the zeroth-order limit, the rate of particle escape converges to the Kramers rate.

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Dynamic Access Control For Multi-Privileged Group Communications, Di Ma, Robert H. Deng, Yongdong Wu, Tieyan Li Oct 2004

Dynamic Access Control For Multi-Privileged Group Communications, Di Ma, Robert H. Deng, Yongdong Wu, Tieyan Li

Research Collection School Of Computing and Information Systems

Recently, there is an increase in the number of group communication applications which support multiple service groups of different access privileges. Traditional access control schemes for group applications assume that all the group members have the same access privilege and mostly focus on how to reduce rekeying messages upon user joining and leaving. Relatively little research effort has been spent to address security issues for group communications supporting multiple access privileges. In this paper, we propose a dynamic access control scheme for group communications which support multiple service groups with different access privileges. Our scheme allows dynamic formation of service …

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The Paradox Of Promoting Creativity In The Asian Classroom: An Empirical Investigation, Aik Kwang Ng, Ian Smith Oct 2004

The Paradox Of Promoting Creativity In The Asian Classroom: An Empirical Investigation, Aik Kwang Ng, Ian Smith

Research Collection School of Social Sciences

To shed light on the paradox of promoting creativity in the Asian classroom, the authors conducted 3 studies. The 1st study found that novice teachers classified student behaviors as desirable but uncreative (DBU) versus creative but undesirable (CBU). The 2nd study found that conservative-autocratic teachers were more likely to encourage DBU behaviors in class, whereas liberal-democratic teachers were more likely to encourage CBU behaviors in class. The 3rd study found that cultural individualism—collectivism had a positive impact on liberal—democratic teaching attitude but a negative impact on conservative—autocratic teaching attitude. In turn, liberal—democratic teaching attitude had a positive impact on the …

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Improving Transliteration With Precise Alignment Of Phoneme Chunks And Using Contextual Features, Wei Gao, Kam-Fai Wong, Wai Lam Oct 2004

Improving Transliteration With Precise Alignment Of Phoneme Chunks And Using Contextual Features, Wei Gao, Kam-Fai Wong, Wai Lam

Research Collection School Of Computing and Information Systems

Automatic transliteration of foreign names is basically regarded as a diminutive clone of the machine translation (MT) problem. It thus follows IBM’s conventional MT models under the sourcechannel framework. Nonetheless, some parameters of this model dealing with zero-fertility words in the target sequences, can negatively impact transliteration effectiveness because of the inevitable inverted conditional probability estimation. Instead of source-channel, this paper presents a direct probabilistic transliteration model using contextual features of phonemes with a tailored alignment scheme for phoneme chunks. Experiments demonstrate superior performance over the source-channel for the task of English-Chinese transliteration.

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Indexing And Matching Of Polyphonic Songs For Query-By-Singing System, Tat-Wan Leung, Chong-Wah Ngo Oct 2004

Indexing And Matching Of Polyphonic Songs For Query-By-Singing System, Tat-Wan Leung, Chong-Wah Ngo

Research Collection School Of Computing and Information Systems

This paper investigates the issues in polyphonic popular song retrieval. The problems that we consider include singing voice extraction, melodic curve representation, and database indexing. Initially, polyphonic songs are decomposed into singing voices and instruments sounds in both time and frequency domains based on SVM and ICA. The extracted singing voices are represented as two melodic curves that model the statistical mean and neighborhood similarity of notes. To speed up the matching between songs and query, we further adopt proportional transportation distance to index the songs as vantage point trees. Encouraging results have been obtained through experiments.

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Deformable Object Model Matching By Topological And Geometric Similarity, Kwok-Leung Tan, Rynson W. H. Lau, Chong-Wah Ngo Oct 2004

Deformable Object Model Matching By Topological And Geometric Similarity, Kwok-Leung Tan, Rynson W. H. Lau, Chong-Wah Ngo

Research Collection School Of Computing and Information Systems

In this paper, we present a novel method for efficient 3D model comparison. The method is designed to match highly deformed models through capturing two types of information. First, we propose a feature point extraction algorithm, which is based on “Level Set Diagram”, to reliably capture the topological points of a general 3D model. These topological points represent the skeletal structure of the model. Second, we also capture both spatial and curvature information, which describes the global surface of a 3D model. This is different from traditional topological 3D matching methods that use only low-dimension local features. Our method can …

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Flexible Verification Of Mpeg-4 Stream In Peer-To-Peer Cdn, Tieyan Li, Yongdong Wu, Di Ma, Robert H. Deng Oct 2004

Flexible Verification Of Mpeg-4 Stream In Peer-To-Peer Cdn, Tieyan Li, Yongdong Wu, Di Ma, Robert H. Deng

Research Collection School Of Computing and Information Systems

The current packet based stream authentication schemes provide effective and efficient authentication over a group of packets transmitted on erasure channels. However, by fixing the packets in transmission, any packet manipulation will cause authentication failure. In p2p content delivery network where a proxy-in-the-middle is able to store, forward, transcode and transform the stream, previous schemes are simply unapplicable. To address the problem, we propose a flexible verification scheme that relies on special stream formats (i.e. Unequal Loss Protection ULP scheme [7]). We apply the so called Unequal Loss Verification ULV scheme into MPEG-4 framework. The encoding, packing, amortizing and verifying …

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Design And Analysis Of A Cooperative Medium Access Scheme For Wireless Mesh Networks, Arup Acharya, Archan Misra, Sorav Bansal Oct 2004

Design And Analysis Of A Cooperative Medium Access Scheme For Wireless Mesh Networks, Arup Acharya, Archan Misra, Sorav Bansal

Research Collection School Of Computing and Information Systems

This paper presents the detailed design and performance analysis of MACA-P, a RTS/CTS based MAC protocol, that enables simultaneous transmissions in wireless mesh networks. The IEEE 802.11 DCF MAC prohibits any parallel transmission in the neighborhood of either a sender or a receiver (of an ongoing transmission). MACA-P is a set of enhancements to the 802.11 MAC that allows parallel transmissions in situations when two neighboring nodes are either both receivers or transmitters, but a receiver and a transmitter are not neighbors. The performance of MACA-P in terms of system throughput is obtained through a simulation of the protocol using …

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Sclope: An Algorithm For Clustering Data Streams Of Categorical Attributes, Kok-Leong Ong, Wenyuan Li, Wee-Keong Ng, Ee Peng Lim Sep 2004

Sclope: An Algorithm For Clustering Data Streams Of Categorical Attributes, Kok-Leong Ong, Wenyuan Li, Wee-Keong Ng, Ee Peng Lim

Research Collection School Of Computing and Information Systems

Clustering is a difficult problem especially when we consider the task in the context of a data stream of categorical attributes. In this paper, we propose SCLOPE, a novel algorithm based on CLOPE's intuitive observation about cluster histograms. Unlike CLOPE however, our algorithm is very fast and operates within the constraints of a data stream environment. In particular, we designed SCLOPE according to the recent CluStream framework. Our evaluation of SCLOPE shows very promising results. It consistently outperforms CLOPE in speed and scalability tests on our data sets while maintaining high cluster purity; it also supports cluster analysis that other …

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A Spectroscopy Of Texts For Effective Clustering, Wenyuan Li, Wee-Keong Ng, Kok-Leong Ong, Ee Peng Lim Sep 2004

A Spectroscopy Of Texts For Effective Clustering, Wenyuan Li, Wee-Keong Ng, Kok-Leong Ong, Ee Peng Lim

Research Collection School Of Computing and Information Systems

For many clustering algorithms, such as k-means, EM, and CLOPE, there is usually a requirement to set some parameters. Often, these parameters directly or indirectly control the number of clusters to return. In the presence of different data characteristics and analysis contexts, it is often difficult for the user to estimate the number of clusters in the data set. This is especially true in text collections such as Web documents, images or biological data. The fundamental question this paper addresses is: ldquoHow can we effectively estimate the natural number of clusters in a given text collection?rdquo. We propose to use …

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Shared-Storage Auction Ensures Data Availability, Hady W. Lauw, Siu-Cheung Hui, Edmund M. K. Lai Sep 2004

Shared-Storage Auction Ensures Data Availability, Hady W. Lauw, Siu-Cheung Hui, Edmund M. K. Lai

Research Collection School Of Computing and Information Systems

Most current e-auction systems are based on the client-server architecture. Such centralized systems provide a single point of failure and control. In contrast, peer-to-peer systems permit distributed control and minimize individual node and link failures' impact on the system. The shared-storage-based auction model described decentralizes services among peers to share the required processing load and aggregates peers' resources for common use. The model is based on the principles of local computation at each peer, direct inter-peer communication, and a shared storage space.

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A Qualitative Investigation On Consumer Trust In Mobile Commerce, Keng Siau, Hong Sheng, Fiona Fui-Hoon Nah, Sidney A. Davis Sep 2004

A Qualitative Investigation On Consumer Trust In Mobile Commerce, Keng Siau, Hong Sheng, Fiona Fui-Hoon Nah, Sidney A. Davis

Research Collection School Of Computing and Information Systems

Mobile commerce represents a significant development in e-commerce, offering accessibility, ubiquity, mobility, and localisation to users. Despite the potential of mobile commerce, trust is a major obstacle in its adoption and development. Many consumers feel uncomfortable with the idea of conducting commerce over wireless, hand-held devices. The focus of this research is to understand trust in mobile commerce and to identify factors that are important for trust development. The research builds on Siau and Shen's framework which depicts two key factors influencing trust in mobile commerce. This research not only validates and expands on the existing framework, but also provides …

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Risk, Return And Risk Aversion: A Behavioral Rendition, Hian Ann, Christopher Ting Sep 2004

Risk, Return And Risk Aversion: A Behavioral Rendition, Hian Ann, Christopher Ting

Research Collection Lee Kong Chian School Of Business

Behavioral finance and classical finance based on utility maximization appear to be mutually exclusive schools of thought. Despite the fundamental difference, we show that behavioral finance also has a linear relation between risk and return. This relation is obtained without the assumptions of market equilibrium, rational expectations, a specific utility function and the market portfolio. In the behavioral approach, the pricing error of CAPM is not an error. It is attributable to the higher-order moments of return. Empirical tests suggest that the relative risk aversion coefficient is positive and time-varying. Moreover, it correlates negatively with both volatility and return.

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Information Contents Of Trade And Quote Imbalances, And The Hypothesis Of Reverse Liquidity, Hian Ann, Christopher Ting Sep 2004

Information Contents Of Trade And Quote Imbalances, And The Hypothesis Of Reverse Liquidity, Hian Ann, Christopher Ting

Research Collection Lee Kong Chian School Of Business

In this paper, we study the information contents of imbalances in trades and quotes emanated from an exchange resembling the one envisioned by Black (1971). We find dollar volume is more informative than number in measuring daily trading and quoting activities. Our measure of quote imbalance permits an investigation on the information asymmetry between market and limit orders. In case illegal insider trading does not occur regularly, we present a hypothesis of reverse liquidity as an alternative interpretation for our empirical findings. It could be that market-order traders charge an implicit liquidity premium for fulfilling the contrarian trading demand of …

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