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Search Publications by: Raghu N Kacker (Fed)

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Displaying 126 - 150 of 195

A Survey of Binary Covering Arrays

April 7, 2011
Author(s)
James F. Lawrence, Raghu N. Kacker, Yu Lei, David R. Kuhn, Michael Forbes
Two-valued covering arrays of strength t are 0--1 matrices having the property that for each t columns and each of the possible 2t sequences of t 0's and 1's, there exists a row having that sequence in that set of t columns. Covering arrays are an

Measures, Uncertainties, and Significance Test in Operational ROC Analysis

January 31, 2011
Author(s)
Jin Chu Wu, Alvin F. Martin, Raghu N. Kacker
In operational ROC (receiver operating characteristic) analysis of fingerprint-image matching algorithms on large datasets, the measures and their accuracies are investigated in the three scenarios: 1) the true accept rate (TAR) of genuine scores at a

Derivation of Isosceles Trapezoidal Distribution

December 1, 2010
Author(s)
Raghu N. Kacker, James F. Lawrence
It is known that, if the mid-point of a rectangular distribution is specified, the half-width is inexactly known, and the state of knowledge about the half-width may be represented by a narrower rectangular distribution then the resulting distribution

Further Studies of Bootstrap Variability for ROC Analysis on Large Datasets

October 11, 2010
Author(s)
Jin Chu Wu, Alvin F. Martin, Raghu N. Kacker
The nonparametric two-sample bootstrap is successfully applied to computing the measurement uncertainties in receiver operating characteristic (ROC) analysis on large datasets in areas such as biometrics, speaker recognition system, etc. To determine the

Validation of Two-Sample Bootstrap in ROC Analysis on Large Datasets Using AURC

October 11, 2010
Author(s)
Jin Chu Wu, Alvin F. Martin, Raghu N. Kacker
Sampling variability can result in uncertainties of measures. The nonparametric two-sample bootstrap method has been used to compute uncertainties of measures in receiver operating characteristic (ROC) analysis on large datasets, such as the standard error

Practical Combinatorial Testing

October 7, 2010
Author(s)
David R. Kuhn, Raghu N. Kacker, Yu Lei
Combinatorial testing can help detect problems like this early in the testing life cycle. The key insight underlying t-way combinatorial testing is that not every parameter contributes to every fault and most faults are caused by interactions between a

Measurement Uncertainties in Speaker Recognition Evaluation

September 15, 2010
Author(s)
Jin Chu Wu, Alvin F. Martin, Craig S. Greenberg, Raghu N. Kacker
The speaker recognition evaluation is an ongoing series of evaluations conducted by NIST. A detection cost function is computed over the sequence of trials provided and used for all speaker detection tests while measuring speaker detection performance. The

A More General Type A Evaluation

September 9, 2010
Author(s)
Ruediger Kessel, Raghu N. Kacker, Klaus-Dieter Sommer
The evaluation of uncertainty according to the Guide to the Expression of Uncertainty in measurement is the internationally agreed procedure to evaluate the complete result statement in measurement including measurement uncertainty. It distinguishes two

Metrological Compatibility and Statistical Consistency

September 5, 2010
Author(s)
Raghu N. Kacker, Ruediger Kessel, Klaus-Dieter Sommer, Xin Bian
The traditional concept of consistency in multiple evaluations of the same measurand is statistical. The statistical view of consistency does not match the modern view of uncertainty in measurement; in particular, it does not apply to the results of

Uncertainty Budgeting for Range Calibration

May 10, 2010
Author(s)
Ruediger Kessel, Raghu N. Kacker, Klaus-Dieter Sommer
The Guide to the Expression of Uncertainty (GUM) in Measurement established a general procedure to evaluate measurement uncertainty. The Guide covers only the evaluation of a single result or a set of results. Modern measurement instruments and procedures

Significance Test in Operational ROC Analysis

April 5, 2010
Author(s)
Jin Chu Wu, Alvin F. Martin, Raghu N. Kacker, Robert C. Hagwood
To evaluate the performance of fingerprint-image matching algorithms on large datasets, a receiver operating characteristic (ROC) curve is applied. From the operational perspective, the true accept rate (TAR) of the genuine scores at a specified false

A Combinatorial Approach to Building Navigation Graphs for Dynamic Web Applications

September 20, 2009
Author(s)
Raghu N. Kacker, David R. Kuhn, James F. Lawrence, Wenhua Wang, Yu Lei, Sreedevi Sampath
Modeling the navigation structure of a dynamic web application is a challenging task because of the presence of dynamic pages. In particular, there are two problems to be dealt with: (1) the page explosion problem, i.e., the number of dynamic pages may be

Scaling Factors and Uncertainties for ab Initio Anharmonic Vibrational Frequencies

August 21, 2009
Author(s)
Russell D. Johnson III, Karl K. Irikura, Raghu N. Kacker, Ruediger Kessel
To predict the vibrational spectra of molecules, ab initio calculations are often used to compute harmonic frequencies, which are usually scaled by empirical factors as an approximate correction for errors in the force constants and for anharmonic effects

Combinatorial Software Testing

August 7, 2009
Author(s)
David R. Kuhn, Raghu N. Kacker, Yu Lei, Justin Hunter
Developers of large data-intensive software often notice an interesting - though not surprising - phenomenon: when usage of an application jumps dramatically, components that have operated for months without trouble suddenly develop previously undetected

Uncertainties in Scaling Factors for ab Initio Vibrational Zero-Point Energies

March 21, 2009
Author(s)
Karl K. Irikura, Russell D. Johnson III, Raghu N. Kacker, Ruediger Kessel
Vibrational zero-point energies (ZPEs) determined from ab initio calculations are often scaled by empirical factors. An empirical scaling factor partially compensates for the effects arising from vibrational anharmonicity and incomplete treatment of

An Interaction-based Test Sequence Generation Approach for Testing Web Applications

December 3, 2008
Author(s)
Wenhua Wang, Sreedevi Sampath, Yu Lei, Raghu N. Kacker
Web applications often use dynamic pages that interact with each other by accessing shared objects, e.g., session objects. Interactions between dynamic pages need to be carefully tested, as they may give rise to subtle faults that cannot be detected by

A Method to Quantify Uncertainty Due to Bias in Chemical Analyses

October 16, 2008
Author(s)
Raghu N. Kacker
A widely accepted approach to assure that the certified property of a chemical reference material is independent of the method of analysis is to analyze by two or more judiciously chosen methods. The statistical problem then is to determine the consensus

On-Line Process Control

October 16, 2008
Author(s)
Raghu N. Kacker, Nien-Fan Zhang
The natural state of manufacturing and measurement processes is usually nonstationary. The methods of statistical process control (SPC) are therefore inappropriate for on-line control. This paper provides a simple and generic protocol for on-line control