Statistics and Probability Commons^™

Solving The Ranking And Selection Indifference-Zone Formulation For Normal Distributions Using Computer Software, Catherine A. Poston

Theses and Dissertations

Ranking and selection procedures are statistical methods used to compare and choose the best among a group of similar statistically distributed populations. The two predominant approaches to solving ranking and selection problems are Guptas subset selection formulation and Bechhofers indifference- zone formulation. For the indifference-zone formulation where the populations have equal sample sizes, Barr and Rizvi developed an integral expression of the probability of correct selection PCS. Given appropriate parameters, the integral expression can be solved to determine the common sample size required to attain a desired PCS. Tables with selected solutions to the integral expression are available for a …

Reproducibility Of Periodontal Probing, Su-Fang Wang

Loma Linda University Electronic Theses, Dissertations & Projects

This study evaluated reproducibility of periodontal probing by conventional manual and automated force-controlled electronic probes. A total of 1206 sites (6 sites per tooth including maxillary and mandibular incisor/canine, premolar, and molar sites) in 15 patients with history of moderate or advanced chronic periodontal disease were examined. Probings included probing pocket depths (PD), as well as probing attachment levels (PAL) from a reference stent. Measurements were recorded to the nearest 0.5 mm with both methods. Patients were examined twice, 7 to 10 days apart. At each visit, all sites were probed first with the conventional probe and then with the …

Developing Prediction Regions For A Time Series Model For Hurricane Forecasting, William Cheman

Theses and Dissertations

In this thesis, a class of time series models for forecasting a hurricanes future position based on its previous positions and a generalized model of hurricane motion are examined and extended. Results of a literature review suggest that meteorological models continue to increase in complexity while few statistical approaches, such as linear regression, have been successfully applied. An exception is provided by a certain class of time series models that appear to forecast storms almost as well as current meteorological models without their tremendous complexity. A suggestion for enhancing the performance of these time series models is pursued through an …

Controllability And Stabilizability Of Coupled Strings With Control Applied At The Coupled Points, Lop-Fat Ho

Mathematics and Statistics Faculty Publications

Controllability and stabilizability of a system of coupled strings with control applied at the coupled points is studied. By investigating the properties of certain exponential series, it is shown that the system is approximate controllable if and only if related systems of uncoupled strings do not share a common eigenvalue. A sufficient condition for exact controllability is also obtained in terms of the Riesz basis properties of those exponential series.

Deadly Confusion: Juror Instructions In Capital Cases, Theodore Eisenberg, Martin T. Wells

Cornell Law Faculty Publications

A fatal mistake. A defendant is sentenced to die because the jury was misinformed about the law. The justice system should be designed to prevent such a tragic error. Yet our interviews with jurors who served in South Carolina capital cases indicate that this nightmare is a reality.

Although our data are limited to South Carolina, the question whether jurors are adequately instructed in capital cases is of national concern. For example, the issue whether jurors should be more fully informed about the alternative to a death sentence has arisen in other states. And the question whether jurors understand the …

Student Fact Book, Fall 1993, Wright State University, Office Of Student Information Systems, Wright State University

Wright State University Student Fact Books

The student fact book has general demographic information on all students enrolled at Wright State University for Fall Quarter, 1993.

Harmonic-Analysis Of Fractal Measures Induced By Representations Of A Certain C*-Algebra, Palle Jorgensen, Steen Pedersen

Mathematics and Statistics Faculty Publications

We describe a class of measurable subsets Ω in R^d such that L²(Ω) has an orthogonal basis of frequencies e_λ(x) = e^i2πλ.x(x ε Ω) indexed by λ ∈ Λ ⊂ R^d. We show that such spectral pairs (Ω, Λ) have a self-similarity which may be used to generate associated fractal measures μ with Cantor set support. The Hilbert space L²(μ) does not have a total set of orthogonal frequencies, but a harmonic analysis of mu may be built instead from a natural representation of the Cuntz …

The Efficiency Of The College Football Betting Market For Southeastern Conference Teams, Ravija Badarinathi, Ladd Kochman

Faculty Articles

To illustrate economic testing and at the same time to conduct an inquiry into the efficiency of the college football betting market, an analysis applies all the betting rules reported by Stark (1992) to the 10 teams comprising the Southeastern Conference before the recent addition of the universities of Arkansas and South Carolina. The combination of 10 teams and 7 conditions produces a total of 70 betting strategies. Since each rule to bet for a team is shadowed by the alternative of betting against that team, the actual number of rules tested is 140. Among those 140 rules, only 7 …

Approximation Methods For Singular Diffusions Arising In Genetics, Nacer E. Abrouk

Mathematical Sciences Technical Reports (MSTR)

Stochastic models in population genetics leading to diffusion equations are considered. When the drift and the square of the diffusion coefficients are polynomials, an infinite system of ordinary differential equations for the moments of the diffusion process can be derived using the Martingale property. An example is provided to show how the classical Fokker-Planck Equation approach may not be appropriate for this derivation. A Gauss-Galerkin method for approximating the laws of the diffusion, originally proposed by Dawson (1980), is examined. In the few special cases for which exact solutions are known, comparison shows that the method is accurate and the …

A Parametric Regression Of The Cost Of Base Realignment Action (Cobra) Model, Douglas D. Hardman, Michael S. Nelson

Theses and Dissertations

This study develops a parametric model that is capable of generating accurate estimates of the costs to close Air Force installations. The new model is based upon, but much simpler to use than, the Cost of Base Realignment Action (COBRA) model. COBRA is an economic cost analysis model that requires a minimum of 250 inputs and as many as 700 inputs. The new parametric model requires just 10 input variables and was developed using least squares multiple regression. Comparison of the new parametric model to COBRA indicates that it captures 91 percent of the variance in cost estimates generated by …

The Impact Of A Primary Health Care Training Program On Morbidity In Kiyeyi, Rural Uganda, 1986-1991 : An Evaluation Of The Uganda-Finland Health Care Program, Marja-Leena Salin

Loma Linda University Electronic Theses, Dissertations & Projects

This study examines the effects of primary health care education efforts in reducing the disease case rates of acute respiratory infections, diarrhoea, malnutrition and measles in a rural Ugandan population between 1986 and 1991.

The intervention, a health education program offered by the Kiyeyi Health Center staff, consisted of a 12-week intensive training for community health workers and traditional birth attendants. Follow-up and supervision took place at regular intervals and continuing education was arranged every other year. Beginning in 1986, this training program was introduced in the first of seven clusters of villages, then expanded successively on an annual basis …

A Non-Human Primate Model For Evaluating A Fenestration Corticotomy Technique, Philip G. M. Khng

Loma Linda University Electronic Theses, Dissertations & Projects

A study model has been designed to evaluate the effectiveness of a new fenestration corticotomy procedure in two non-human primates Macaca fasicularis.

The objective of this study was to evaluate the efficacy of a new conservative corticotomy procedure to facilitate dental translation using fenestrations. This pilot study compared treatment and control quadrants of each individual animal's maxilla and mandible with both having the same retraction appliance and force on the 2nd premolar following extraction of the 1st molars. The null hypothesis stated that there was no significant statistical difference between the new conservative corticotomy procedure (fenestrations) when compared with …

Diet And Colon Cancer Risk In The Population Of Thailand, Nithat Sirichotiratana

Loma Linda University Electronic Theses, Dissertations & Projects

Epidemiological studies have emphasized environmental influences, especially a diet high in animal fat and low in fiber, as major risk factors for colon cancer. In order to examine the relationship between dietary fat and fiber and occurrence of colon cancer, patient medical records from the National Cancer Institute between 1981-1991 were used for the first hospital-based case-control study of diet and colon cancer in Thailand. These records included a total of 168 cases and 357 controls. Data on the frequency consumption of various food items were obtained by using an existing food frequency questionnaire, completed as part of patient’s history …

Breaking The Matches In A Paired T-Test For Community Interventions When The Number Of Pairs Is Small, Paula Diehr, Don C. Martin, Thomas D. Koepsell, Allen D. Cheadle

UW Biostatistics Working Paper Series

There is considerable interest in community interventions for health promotion, where the community is the experimental unit. Because such interventions are expensive, the number of experimental units (communities) is usually small. Because of the small number of communities involved, investigators often match treatment and control communities on demographic variables before randomization to minimize the possibility of a bad split. Unfortunately, matching has been shown to decrease the power of the design when the number of pairs is small, unless the matching variable is very highly correlated with the outcome variable (in this case, with change in the health behavior). We …

Tracking Plasma Lactate Concentration In Vivo With A Catheter-Tip L-Lactate Sensor, Brett T. Weinzapfel, Mark D. Ball, Lee R. Waite, Nacer E. Abrouk, Shun P. Lim

Mathematical Sciences Technical Reports (MSTR)

To circumvent the problems of repeated blood sampling for in vitro analysis, a catheter-tip L-lactate sensor has been developed. The sensor was tested in anesthetized pigs (n=6). The sensor in vivo tracked the lactate concentration non-linearly, seeming to obey Michaelis-Menten kinetics. Calibration time was short, typically 1.5 min per lactate standard. Furthermore, time drift was small, typically -1.3% to -3.3% per hour of in vivo use.

Dynamic Id3: A Symbolic Learning Algorithm For Many-Valued Attribute Domains, Roger Gallion, Chaman Sabharwal, Daniel C. St. Clair, William E. Bond

Computer Science Faculty Research & Creative Works

Quinlan's ID3 machine learning algorithm induces classification trees (rules) from a set of training examples. The algorithm is extremely effective when training examples are composed of attributes whose values are taken from small discrete domains. The classification accuracy of ID3-produced trees on domains whose attributes are many-valued tends to be marginal due to the large number of possible values which may be associated with each attribute. Attempts to solve this problem by a priori grouping of attribute values into distinct subsets has met with limited success. The dynamic ID3 algorithm improves the performance of ID3 on this type of problem …

Identification Of Significant Outliers In Time Series Data, Keri L. Robinson

Theses and Dissertations

This thesis examines the feasibility of using least median of squares (LMS) procedure applied to a reweighted least squares (RLS) autoregression model to identify significant outliers in time series data. The time series were analyzed for data points that were outliers. In order to perform detailed analysis on an outlier. the analyst must be able to determine that an outlier data point is significantly different from normally distributed data. This thesis examines a new method for identifying these outliers. Data from the field were characterized and fit with time series models using an autoregressive reweighted least squares routine (ARRLS) derived …

A Modified Anderson Darling Goodness-Of-Fit Test For The Gamma Distribution With Unknown Scale And Location Parameters, Tamer Ozmen

Theses and Dissertations

A new modified Anderson-Darling goodness-of-fit test is introduced for the three-parameter Gamma distribution when the location parameter is found by minimum distance estimation and scale parameter by maximum likelihood estimation. Monte Carlo simulation studies were performed to calculate the critical values for A-D test when A-D statistic is minimized. These critical values are then used for testing whether a set of observations follows a Gamma distribution when the scale and location parameters axe unspecified and are estimated from the sample. Functional relationship between the critical values of A-D is also examined for each shape parameter by the variables, sample size …

A New Goodness-Of-Fit Test For The Weibull Distribution Based On Spacings, Mark C. Coppa

Theses and Dissertations

The critical values for a new goodness-of-fit test based on spacings are generated for the Weibull distribution when the shape parameter is known. The critical values are used for testing whether a set of observations follow a Weibull distribution when the scale and location parameters are unknown. A Monte Carlo simulation with 10,000 iterations is used to generate the critical values for sample sizes 5(5)35 at shape parameters k equal to 0.5(0.5)1.5 and for sample sizes 5(5)20 at shape parameters k = 2.0(1.0)4.0. A Monte Carlo power study of the Z* test statistic using 5000 iterations is accomplished using nine …

Modified Anderson-Darling And Cramer-Von Mises Goodness-Of-Fit Tests For The Normal Distribution, David A. Gwinn Sr.

Theses and Dissertations

New techniques for calculating goodness-of-fit statistics for normal distributions with parameters estimated from the sample are investigated. Samples are generated for a Normal(0,1) distribution. Critical values are calculated for five modifications to the Anderson-Darling statistic and five modifications to the Cramer-Von Mises statistic. An extensive power study is done to test the power of the new statistics versus the power of the unmodified statistics. Powers of six of the new statistics show minimal to no improvement, two of the new statistics show a marked decrease in power, and two of the new statistics show an overall increase in power over …

A Modified Chi-Squared Goodness-Of-Fit Test For The Three-Parameter Gamma Distribution With Unknown Parameters, Thomas J. Sterle

Theses and Dissertations

A modified chi-squared goodness-of-fit test was created for the gamma distribution in the case where all three parameters must be estimated from the sample. Critical values are generated using a Monte Carlo simulation procedure with 5000 repetitions each. Random samples of 8 different sizes were drawn from gamma distributions with shape parameters 1, 1.5, 2., and 2.5. The shape, scale, and location parameters were then estimated from each sample, using an iterative technique combining the maximum likelihood and minimum distance methods, enabling, computation of the chi-squared statistics and critical values. The same process is used to generate random samples, parameter …

A Comparison Of Variable Selection Criteria For Multiple Linear Regression: A Second Simulation Study, David P. Woollard

Theses and Dissertations

This thesis implements a variable selection method proposed by Alan J. Miller, and makes an extension of Ross J. Hansen's 1988 thesis research by comparing the methods he examined: Minimum MSE, Minimum Sp, and Minimum Cp with Miller's method. Response Surface methodology is employed with two performance measures: the percentage of correct variables in a model and the Theoretical Mean Squared Error of Prediction (TMSEP). Each technique is applied on generated data with known multicollinearities, variances, random predictors, and sample sizes. Both performance measures are computed for models selected under each technique. A full factorial design using each performance measure …

Modeling And Analysis For Laser Beam Induced Current Images In Semiconductors, Weifu Fang, Stavros Busenberg, Kazufumi Ito

Mathematics and Statistics Faculty Publications

A mathematical model is developed for the new nondestructive optical technique called laser-beam-induced currents (LBIC), which can be used to detect electrically active regions and defects in semiconductors. The wellposedness of the model equations is shown, and an approximate model that simplifies the numerical implementation of the identification problem is obtained. Some numerical results are presented to show that the approximate model preserves the significant features that the LBIC technique has been experimentally shown to possess.

The Full Group Of A Countable Measurable Equivalence Relation, Richard Mercer

Mathematics and Statistics Faculty Publications

We study the group of all ''R-automorphisms'' of a countable equivalence relation R on a standard Borel space, special Borel automorphisms whose graphs lie in R. We show that such a group always contains periodic maps of each order sufficient to generate R. A construction based on these periodic maps leads to totally nonperiodic R-automorphisms all of whose powers have disjoint graphs. The presence of a large number of periodic maps allows us to present a version of the Rohlin Lemma for R-automorphisms. Finally we show that this group always contains copies of free …

Feasibility Test Verification Method For Nonsymmetric Release Time Task Scheduling, R. G. Karl, T. L. Lo, Daniel C. St. Clair

Mathematics and Statistics Faculty Research & Creative Works

This paper discusses problems associated with scheduling periodic task on a uniprocessor in a hard, real-time processing environment using a static-priority, preemptive-resume operating system. Task sets containing a single periodic task with two Ned release periocis of unequal length are examined. Ihe nonsymmetric scheduling algorithm is based on the rate monotonic scheduling algorithm which assigns higher task priorities to tasks with shorter release periods. me effects on processor utilization using two dirkrent priority assignment schemes are examined; one with task priorities sorted by the average release periods and the other with priorities sorted using the short nonsymmetric task period with …

Fixed Points For Pairs Of Mappings In D-Complete Topological Spaces, Troy L. Hicks, B. E. Rhoades

Mathematics and Statistics Faculty Research & Creative Works

Several important metric space fixed point theorems axe proved for a large class of non-metric spaces. In some cases, the metric space proofs need only minor changes. This is surprising since the distance function used need not be symmetric and need not satisfy the triangular inequality. © 1993, Hindawi Publishing Corporation. All rights reserved.

The Next Linear Collider Test Accelerator, R. D. Ruth, C. Adolphsen, K. Bane, R. F. Boyce, D. L. Burke, R. Calin, G. Caryotakis, R. Cassel, Stephen L. Clark, H. Deruyter, K. Fant, R. Fuller, S. Heifets, H. Hoag, R. Humphrey, S. Kheifets, R. Koontz, N. M. Kroll, R. T. Lavine, G. A. Loew, A. Menegat, R. H. Miller, C. Nantista, J. M. Patterson, C. Pearson, R. Phillips, J. Rifkin, J. Spencer, S. Tantawi, K. A. Thompson, A. Vlieks, V. Vylet, J. W. Wang, P. B. Wilson, A. Yeremian, B. Youngman

Mathematics and Statistics Faculty Research & Creative Works

During the past several years, there has been tremendous progress on the development of the RF system and accelerating structures for a Next Linear Collider (NLC). Developments include high-power klystrons, RF pulse compression systems and damped/detuned accelerator structures to reduce wakefields. In order to integrate these separate development efforts into an actual X-band accelerator capable of accelerating the electron beams necessary for an NLC, we are building an NLC Test Accelerator (NLCTA). The goal of the NLCTA is to bring together all elements of the entire accelerating system by constructing and reliably operating an engineered model of a high-gradient linac …

On Infinite Delay Integral Equations Having Nonlinear Perturbations, Muhammad Islam

Mathematics Faculty Publications

The existence of bounded solutions and periodic solutions is studied for a system of infinite delay integral equations having nonlinear perturbations. An equivalent system of equations is obtained in terms of the resolvent kernel. Then the existence results are shown for the equivalent equations. Contraction principle, Schauder’s fixed point theorem, and monotone method are used in the study.

Ua56/1 Fact Book, Wku Institutional Research

WKU Administration Documents

Statistical and demographic profile of WKU.

The Value And Utility Of Animals In Research, Andrew N. Rowan, Joan C. Weer

Validation of Animal Experimentation Collection

The Tufts University School of Veterinary Medicine, Center for Animals and Public Policy, sponsored an invitational seminar, The Value and Utility of Animals in Research, on October 14, 1993, at the Hyatt Regency Hotel in Baltimore, Maryland. This seminar was the second in a series of three organized by the Center for Animals and Public Policy and supported by The Pew Charitable Trusts to deal with issues relating to the use of animals in research. The first seminar, Biology Education and Animals: Opportunities and Issues, was held in the spring of 1993. The third meeting, at the National Press Club …