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Computational Finance Models, Michael Gene Hilgers Jan 2000

Computational Finance Models, Michael Gene Hilgers

Business and Information Technology Faculty Research & Creative Works

The author discusses his involvement in developing computational finance software. These computational finance models attempt to model the randomness of a stock's price. At a fixed future time, a stock's price is modeled as a random variable with a normal distribution centered about the current price adjusted with a simple growth multiplier. The standard deviation of this normal distribution depends on the length of time into the future one peers and the volatility of the market. As the market becomes more volatile and we look further ahead, the less likely the stock will have a price near the adjusted current …

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Adaptive Information Filtering: Evolutionary Computation And N-Gram Representation, Daniel R. Tauritz, Ida G. Sprinkhuizen-Kuyper Jan 2000

Adaptive Information Filtering: Evolutionary Computation And N-Gram Representation, Daniel R. Tauritz, Ida G. Sprinkhuizen-Kuyper

Computer Science Faculty Research & Creative Works

Adaptive Information Filtering (AIF) is concerned with filtering information streams in changing environments. The changes may occur both on the transmission side (the nature of the streams can change) and on the reception side (the interests of a user can change). The research described in this paper details the progress made in a prototype AIF system based on weighted n-gram analysis and evolutionary computation. A major advance is the design and implementation of an n-gram class library allowing experimentation with different values of n instead of solely with 3-grams as in the past. The new prototype system was tested on …

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Detecting And Representing Relevant Web Deltas Using Web Join, Sanjay Kumar Madria, Wee Keong, Ee-Peng Lim, Sourav S. Bhowmick Jan 2000

Detecting And Representing Relevant Web Deltas Using Web Join, Sanjay Kumar Madria, Wee Keong, Ee-Peng Lim, Sourav S. Bhowmick

Computer Science Faculty Research & Creative Works

We show how to detect and represent Web deltas, i.e., changes in Web information, that are relevant to a user's query in the context of our Web warehousing system called WHOWEDA (Warehouse of Web Data). In WHOWEDA, Web information are materialized views stored in Web tables and can be manipulated and analyzed using a set of Web algebraic operators. We present a mechanism to detect relevant Web deltas using Web join and outer Web join. We show how to represent these changes using delta Web tables.

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Reducing Cognitive Overheads In A Web Warehouse Using Reverse-Osmosis, Sanjay Kumar Madria, Wee Keong Ng, Ee-Peng Lim, Sourav S. Bhowmick Jan 2000

Reducing Cognitive Overheads In A Web Warehouse Using Reverse-Osmosis, Sanjay Kumar Madria, Wee Keong Ng, Ee-Peng Lim, Sourav S. Bhowmick

Computer Science Faculty Research & Creative Works

This paper provides a quantitative analysis of reducing cognitive overheads in a Web warehouse using an important class of operation called reverse osmosis. The analysis is used to examine two different cognitive overheads of locating relevant nodes or information and display time of a Web table. A reverse-osmosis operation enables us to eliminate in relevant information from a collection of Web documents stored in the form of a Web table. We call such an operation reverse-osmosis because it is analogous to the reverse osmosis process in the field of water purification. We discuss a formal algorithm of the reverse-osmosis operation

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Search For R-Parity Violating Decays Of Supersymmetric Particles In E+E- Collisions At Centre-Of-Mass Energies Near 183 Gev, R. Barate, M. Thulasidas Jan 2000

Search For R-Parity Violating Decays Of Supersymmetric Particles In E+E- Collisions At Centre-Of-Mass Energies Near 183 Gev, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

Searches for pair-production of supersymmetric particles under the assumption that R-parity is violated via a single dominant LLE¯LLE¯, LQD¯LQD¯ or U¯D¯D¯U¯D¯D¯ coupling are performed using the data collected by the ALEPH collaboration at centre-of-mass energies of 181–184 GeV. The observed candidate events in the data are in agreement with the Standard Model expectations. Upper limits on the production cross-sections and lower limits on the masses of charginos, sleptons, squarks and sneutrinos are derived.

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Study Of Fermion Pair Production In E+E- Collisions At 130-183 Gev, R. Barate, M. Thulasidas Jan 2000

Study Of Fermion Pair Production In E+E- Collisions At 130-183 Gev, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

The cross sections and forward-backward asymmetries of hadronic and leptonic events produced in e+e−e+e− collisions at centre-of-mass energies from 130 to 183 GeV are presented. Results for e+e−e+e−, μ+μ−μ+μ−, τ+τ−τ+τ−, qq¯qq¯, bb¯bb¯ and cc¯cc¯ production show no significant deviation from the Standard Model predictions. This enables constraints to be set upon physics beyond the Standard Model such as four-fermion contact interactions, leptoquarks, Z′Z′ bosons and R-parity violating squarks and sneutrinos. Limits on the energy scale ΛΛ of e+e−ff¯e+e−ff¯ contact interactions are typically in the range from 2 to 10 TeV. Limits on R-parity violating sneutrinos reach masses of a few …

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On-Line Bayesian Tree-Structured Transformation Of Hidden Markov Models For Speaker Adaptation, Shaojun Wang, Yunxin Zhao Dec 1999

On-Line Bayesian Tree-Structured Transformation Of Hidden Markov Models For Speaker Adaptation, Shaojun Wang, Yunxin Zhao

Kno.e.sis Publications

This paper presents a new recursive Bayesian learning approach for transformation parameter estimation in speaker adaptation. Our goal is to incrementally transform (or adapt) the entire set of HMM parameters for a new speaker or new acoustic enviroment from a small amount of adaptation data. By establishing a clustering tree of HMM Gaussian mixture components, the finest affine transformation parameters for individual HMM Gaussian mixture components can be dynamically searched. The on-line Bayesian learning technique proposed in our recent work is used for recursive maximum a posteriori estimation of affine transformation parameters. Speaker adaptation experiments using a 26-letter English alphabet …

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Implementing Sap R/3 At The University Of Nebraska, T. Sieber, Keng Siau, Fiona Fui-Hoon Nah, M. Sieber Dec 1999

Implementing Sap R/3 At The University Of Nebraska, T. Sieber, Keng Siau, Fiona Fui-Hoon Nah, M. Sieber

Research Collection School Of Computing and Information Systems

In April 1995, I asked four Nebraskans from the private sector and four senior people of the University to review the administrative processes of the University of Nebraska. In the appointment letter for this Task Force, I noted that many current administrative processes need to be examined to improve quality and productivity.

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Measuring Information Quality Of Web Site: Development Of Instrument, P. Katerattanakul, Keng Siau Dec 1999

Measuring Information Quality Of Web Site: Development Of Instrument, P. Katerattanakul, Keng Siau

Research Collection School Of Computing and Information Systems

Web sites have been extensively used to provide information to consumers. While practitioners and researchers have proposed different criteria for effective Web site design based on common sense, intuition, and rules-ofthumb, effective Web site design focusing on the quality of the information it provides has rarely been studied. In this research, we propose a framework and develop an instrument to measure the information quality of individual or personal Web sites. The theoretical foundation of this research is the information quality framework. The proposed framework and instrument were tested in an individual or personal Web site context.

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Mining Multiple-Level Association Rules In Large Databases, Jiawei Han, Yongjian Fu Dec 1999

Mining Multiple-Level Association Rules In Large Databases, Jiawei Han, Yongjian Fu

Computer Science Faculty Research & Creative Works

A top-down progressive deepening method is developed for efficient mining of multiple-level association rules from large transaction databases based on the Apriori principle. A group of variant algorithms is proposed based on the ways of sharing intermediate results, with the relative performance tested and analyzed. The enforcement of different interestingness measurements to find more interesting rules, and the relaxation of rule conditions for finding `level-crossing' association rules, are also investigated in the paper. Our study shows that efficient algorithms can be developed from large databases for the discovery of interesting and strong multiple-level association rules.

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Optimal Power Allocation In Cdma Forward Link Using Dependency Between Pilot And Traffic Channels, Seung Jong Park, Dongwoo Kim, Chang Yeon Kim Dec 1999

Optimal Power Allocation In Cdma Forward Link Using Dependency Between Pilot And Traffic Channels, Seung Jong Park, Dongwoo Kim, Chang Yeon Kim

Computer Science Faculty Research & Creative Works

This paper shows a new method for minimizing the transmit power on CDMA forward link channels. Different from previous works, the proposed method uses the dependency that exists between the respective signal qualities of the pilot channel and traffic channels. Since present CDMA forward link exploits coherent demodulation with continuously transmitting pilot signals, the stronger the pilot channel is, the less traffic power may be required while the same transmission quality is maintained. With laboratory tests, the dependency is graphed. And then an optimal pilot signal quality is found, which minimizes the total transmit power. Considering various mobile environments, -10 …

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The Window Distribution Of Multiple Tcps With Random Loss Queues, Archan Misra, Teunis Ott, John Baras Dec 1999

The Window Distribution Of Multiple Tcps With Random Loss Queues, Archan Misra, Teunis Ott, John Baras

Research Collection School Of Computing and Information Systems

Two approximate techniques for analyzing the window size distribution of TCP flows sharing a RED-like bottleneck queue are presented. Both methods presented first use a fixed point algorithm to obtain the mean window sizes of the flows, and the mean queue length in the bottleneck buffer. The simpler of the two methods then uses the ‘square root formula’ for TCP; the other method is more complicated. More often than not, the simpler method is slightly more accurate; this is probably due to the fact that window sizes of the different flows are negatively correlated.

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Mpeg-4 Systems And Applications, Hari Kalva, Lai-Tee Cheok, Alexandros Eleftheriadis Nov 1999

Mpeg-4 Systems And Applications, Hari Kalva, Lai-Tee Cheok, Alexandros Eleftheriadis

Research Collection School Of Computing and Information Systems

MPEG-4, under the auspices of the ISO, is specifying tools to enable object-based audio-visual presentations [3]. These include tools to encode individual objects, compose presentations with objects, store these object-based presentations and access these presentations in a distributed manner over networks. The main distinguishing feature of object-based audio-visual presentations is the scene composition at the user terminal. The objects that are part of a scene are composed and displayed at the user end as opposed to encoding the composed scenes as is done in the case of MPEG-2. Such object-based representation and presentation has several benefits including compression efficiency and …

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Zbroker: A Query Routing Broker For Z39.50 Databases, Yong Lin, Jian Xu, Ee Peng Lim, Wee-Keong Ng Nov 1999

Zbroker: A Query Routing Broker For Z39.50 Databases, Yong Lin, Jian Xu, Ee Peng Lim, Wee-Keong Ng

Research Collection School Of Computing and Information Systems

A query routing broker is a software agent that determines from a large set of accessing information sources the ones most relevant to a user's information need. As the number of information sources on the Internet increases dramatically, future users will have to rely on query routing brokers to decide a small number of information sources to query without incurring too much query processing overheads. In this paper, we describe a query routing broker known as ZBroker developed for bibliographic database servers that support the Z39.50 protocol. ZBroker samples the content of each bibliographic database by using training queries and …

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What Is Y2k And How Did The University Of Nevada System Solve It?, Diane R. Dietrich Oct 1999

What Is Y2k And How Did The University Of Nevada System Solve It?, Diane R. Dietrich

UNLV Theses, Dissertations, Professional Papers, and Capstones

The turn of the century change from 1999 to 2000 will create chaos for the world's computer systems. This paper will discuss the causes of the Y2K problem, the reaction to this problem by the University of Nevada System Computer Services and possible repercussions of this problem for Nevada, the United States and the world.

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Design Approaches To Model-Based Simulation In Intelligent Computer Assisted Instruction, Bjoern Helfesrieder, Venky Shankararaman Sep 1999

Design Approaches To Model-Based Simulation In Intelligent Computer Assisted Instruction, Bjoern Helfesrieder, Venky Shankararaman

Research Collection School Of Computing and Information Systems

Model-based simulation systems have been created in various fields of engineering to train personnel or students in operation, maintenance and troubleshooting of complex devices and systems. A review of literature indicates a lack of good overviews of the approaches to system design of model-based training simulations in Intelligent Computer Assisted Instruction (ICAI). Though single systems have to some extent been evaluated with regard to their performance, an organised evaluation, especially a comparative evaluation of the systems that have been created within the field is lacking. To be able to successfully conduct an in-depth review under these conditions, we concentrate and …

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Xcert Software, Inc., Keng Siau Sep 1999

Xcert Software, Inc., Keng Siau

Research Collection School Of Computing and Information Systems

Xcert’s business is in developing Internet and Intranet security enhancement technology. Xcert was founded in April 1996 by Andrew Csinger and Pat Richard and was headquartered in Vancouver, Canada. Xcert’s solution to Internet security was a public key infrastructure (PKI). PKI is a system of digital certi® cates, certi® cate authorities (CAs) and other registration authorities that verify and authenticate the validity of each party involved in an Internet transaction. Xcert’s PKI technology allows organizations of any size to issue digital certi® cates to their members. These organizations become their own CA and are empowered to issue digital certi® cates …

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Wedagen: A Synthetic Web Database Generator, Pallavi Priyardarshini, Fengqiong Qin, Ee Peng Lim, Wee-Keong Ng Sep 1999

Wedagen: A Synthetic Web Database Generator, Pallavi Priyardarshini, Fengqiong Qin, Ee Peng Lim, Wee-Keong Ng

Research Collection School Of Computing and Information Systems

At the Centre for Advanced Information Systems (CAIS), a Web warehousing system is being developed to store and manipulate Web information. The system named WHOWEDA (WareHouse Of WEb DAta) stores extracted Web information as Web tables and provides several Web operators, eg. Web join, Web select, global coupling, etc., to manipulate Web tables. During the implementation of WHOWEDA, it is necessary to perform systematic testing on the system and to evaluate its system performance. While it is possible for WHOWEDA to be tested or evaluated using actual Web pages downloaded from WWW, the amount of time required for such testing …

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Research Issues In Web Data Mining, Sanjay Kumar Madria, Sourav S. Bhowmick, Wee-Keong Ng, Ee Peng Lim Sep 1999

Research Issues In Web Data Mining, Sanjay Kumar Madria, Sourav S. Bhowmick, Wee-Keong Ng, Ee Peng Lim

Research Collection School Of Computing and Information Systems

In this paper, we discuss mining with respect to web data referred here as web data mining. In particular, our focus is on web data mining research in context of our web warehousing project called WHOWEDA (Warehouse of Web Data). We have categorized web data mining into threes areas; web content mining, web structure mining and web usage mining. We have highlighted and discussed various research issues involved in each of these web data mining category. We believe that web data mining will be the topic of exploratory research in near future.

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Locating Web Information Using Web Checkpoints, Aik Kee Luah, Wee-Keong Ng, Ee Peng Lim, Wee Peng Lee, Yinyan Cao Sep 1999

Locating Web Information Using Web Checkpoints, Aik Kee Luah, Wee-Keong Ng, Ee Peng Lim, Wee Peng Lee, Yinyan Cao

Research Collection School Of Computing and Information Systems

Conventional search engines locate information by letting users establish a single web checkpoint1. By specifying one or more keywords, users direct search engines to return a set of documents that contain those keywords. From the documents (links) returned by search engines, user proceed to further probe the WWW from there. Hence, these initial set of documents (contingent upon the occurrence of keyword(s)) serve as a web checkpoint. Generally, these links are numerous and may not result in much fruitful searches. By establishing multiple web checkpoints, a richer and controllable search procedure can be constructed to obtain more relevant Web information. …

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Motion Tracking Of Human Mouth By Generalized Deformable Models, Syin Chan, Chong-Wah Ngo, Kok F. Lai Sep 1999

Motion Tracking Of Human Mouth By Generalized Deformable Models, Syin Chan, Chong-Wah Ngo, Kok F. Lai

Research Collection School Of Computing and Information Systems

We propose and evaluate four trackers for tracking the shape, motion and deformation of a human mouth in video sequences. The trackers are suitable for use in very low bitrate video coding systems. (C) 1999 Elsevier Science B.V. All rights reserved.

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Internet, World Wide Web, And Creativity, Keng Siau Sep 1999

Internet, World Wide Web, And Creativity, Keng Siau

Research Collection School Of Computing and Information Systems

The growth of the Internet has been the most astonishing technological and social phenomenon of the last decade of this century. In 1990 only a few academics had heard of it; now, more than 50 million people use it. By the turn of the century, that figure could be 100–200 million. So far, the network's only constant has been that the number of new users has doubled almost every 12–18 months. Most organizations have or will soon have Internet access. The popularity of Internet provides a tremendous opportunity for individuals and organizations to explore its features and services for electronic …

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Non-Repudiation In An Agent-Based E-Commerce System, Chin Chuan Liew, Wee-Keong Ng, Ee Peng Lim, Beng Suang Tan, Kok-Leong Ong Sep 1999

Non-Repudiation In An Agent-Based E-Commerce System, Chin Chuan Liew, Wee-Keong Ng, Ee Peng Lim, Beng Suang Tan, Kok-Leong Ong

Research Collection School Of Computing and Information Systems

Abecos is an agent-based e-commerce system under development at the Nanyang Technological University. A key factor in making this system usable in practice is strict security controls. One aspect of security is the provision of non-repudiation services. As protocols for non-repudiation have focused on -message non-repudiation, its adaptation to afford non-repudiation in a communication session for two agents in Abecos is inefficient. In this work, we investigate and propose a protocol for enforcing non-repudiation in a session. The protocol is believed to be applicable in any e-commerce system; agent- or not agent-based.

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Artificial Intelligence Approach To Analyzing The Bullwhip Effect In Supply Chains, C. Qing, Keng Siau Aug 1999

Artificial Intelligence Approach To Analyzing The Bullwhip Effect In Supply Chains, C. Qing, Keng Siau

Research Collection School Of Computing and Information Systems

Supply chain management critically affects businesses’ abilities to obtain and sustain competitive advantages. The bullwhip effect, however, presents a challenge for successful supply chain management by amplifying demands in the supply chains. This paper presents a systematic approach to tackle the issue of bullwhip effect. Firstly, we define the supply chain under a multiagent framework. Secondly, the group problem solving paradigm, which is a rule learning approach, is proposed to enhance the decision making process within the supply chain framework. The group problem solving paradigm is also suggested as a means to alleviate the bullwhip effect. The paper concludes with …

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Knowledge Sharing With Customers On The Www: Approaches By National Tourism Organizations, Xinran You, Joseph O'Leary, Fiona Fui-Hoon Nah Aug 1999

Knowledge Sharing With Customers On The Www: Approaches By National Tourism Organizations, Xinran You, Joseph O'Leary, Fiona Fui-Hoon Nah

Research Collection School Of Computing and Information Systems

The importance of knowledge management has been emphasized increasingly in recent literature. Knowledge has been regarded as the most important corporate asset in an organization (Nonaka and Takeuchi, 1995). But what is knowledge? According to Harris (1996), "when information is combined with context and experience, it becomes knowledge". Hence, knowledge is the integration of information, context, and experience (Ponelis and Fairer-Wessels, 1998). In the tourism context of this paper, there are two components of knowledge: (1) customer knowledge--understanding of customers by marketers that leads to more effective marketing actions; and (2) destination knowledge that either the travelers or travel experts …

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Website Design: The Concepts Of Informational And Computational Equivalence, Keng Siau Aug 1999

Website Design: The Concepts Of Informational And Computational Equivalence, Keng Siau

Research Collection School Of Computing and Information Systems

“To the end users, the user interface is the system.” This slogan has been widely used in human-computer interaction field to stress the importance of user interface design. In the Internet and electronic commerce area, the website is not only the system, but it also projects an image of the organization in cyberspace. The design of websites is central to businesses as they create the first impression of organizations to visitors. For a virtual organization, the website is also the only medium that visitors rely on to form their impression of the organization. In this paper, we look at theories …

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Cluster-Based Database Selection Techniques For Routing Bibliographic Queries, Jian Xu, Ee Peng Lim, Wee-Keong Ng Aug 1999

Cluster-Based Database Selection Techniques For Routing Bibliographic Queries, Jian Xu, Ee Peng Lim, Wee-Keong Ng

Research Collection School Of Computing and Information Systems

In this paper, we focus on the database selection problem in the context of a global digital library consisting of a large number of online bibliographic servers. Each server hosts a bibliographic database that contains bibliographic records each of which consists of text values for a number of pre-defined bibliographic attributes such as title, author, call number, subject, etc.. Each bibliographic database supports user queries on the bibliographic attributes. Since bibliographic records are relatively small in size, we only consider bibliographic databases that support boolean queries on the bibliographic attributes, and the query results are not ranked. While focusing on …

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A Recurring Improvisational Methodology For Change Management In Erp Implementation, Michelle Sieber, Fiona Fui-Hoon Nah Aug 1999

A Recurring Improvisational Methodology For Change Management In Erp Implementation, Michelle Sieber, Fiona Fui-Hoon Nah

Research Collection School Of Computing and Information Systems

Change has become an ongoing phenomenon and business process re-engineering has become a necessity for survival of organizations as we approach the 21st century. As participants in this ever-changing working environment, we must be innovative in managing change as it affects both our professional and personal lives. One of the innovative ways to manage change in the implementation of an enterprise resource planning (ERP) system is to adopt a comprehensive change management methodology. In this research, we propose the use of the recurring improvisational change methodology for managing such change. This research is also aimed at implementing the improvisational change …

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The Robustness Of Relaxation Rates In Constraint Satisfaction Networks, Tony R. Martinez, Dan A. Ventura, D. Randall Wilson, Brian Moncur Jul 1999

The Robustness Of Relaxation Rates In Constraint Satisfaction Networks, Tony R. Martinez, Dan A. Ventura, D. Randall Wilson, Brian Moncur

Faculty Publications

Constraint satisfaction networks contain nodes that receive weighted evidence from external sources and/or other nodes. A relaxation process allows the activation of nodes to affect neighboring nodes, which in turn can affect their neighbors, allowing information to travel through a network. When doing discrete updates (as in a software implementation of a relaxation network), a goal net or goal activation can be computed in response to the net input into a node, and a relaxation rate can then be used to determine how fast the node moves from its current value to its goal value. An open question was whether …

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Combining Cross-Validation And Confidence To Measure Fitness, Tony R. Martinez, D. Randall Wilson Jul 1999

Combining Cross-Validation And Confidence To Measure Fitness, Tony R. Martinez, D. Randall Wilson

Faculty Publications

Neural network and machine learning algorithms often have parameters that must be tuned for good performance on a particular task. Leave-one-out cross-validation (LCV) accuracy is often used to measure the fitness of a set of parameter values. However, small changes in parameters often have no effect on LCV accuracy. Many learning algorithms can measure the confidence of a classification decision, but often confidence alone is an inappropriate measure of fitness. This paper proposes a combined measure of Cross- Validation and Confidence (CVC) for obtaining a continuous measure of fitness for sets of parameters in learning algorithms. This paper also proposes …

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