Physical Sciences and Mathematics Commons^™

A Simple Alternative To The Standard Statistical Model For The Analysis Of Field Experiments With Latin Square Designs, C. Philip Cox, Jeff B. Meeker

Conference on Applied Statistics in Agriculture

Latin Square (LS) designs have long been advocated for field crop experiments on the grounds that '. . . soil fertility and other variations in two directions are controlled.' As counter-evidence, the published standard analyses of eight LS experiments showed that in only two did the sum of squares for both between-rows and between-columns account for appreciable background variability.

Regarding the background concomitant variability as a continuous surface to which treatment effects are additive, it is suggested that a contributory shortcoming of the standard model is that it admits only a restricted class of surfaces because parameters for warp, or …

Designed Experiments In The Presence Of Spatial Correlation, David B. Marx

Conference on Applied Statistics in Agriculture

Soil heterogeneity is generally the major cause of variation in plot yield data and the difficulty of its interpretation. If a large degree of variability is present at a test site, some method of controlling it must be found. Controlling experimental variability can be achieved either by good experimental design or by analysis procedures which account for the spatial correlation. Classical designs are only moderately equipped to adjust for spatially correlated data. More complex designs including nearest neighbor designs, Williams designs, and certain restricted Latin square designs are developed for field experimentation when spatial correlation causes classical designs to be …

Confidence Intervals For Soil Properties Based On Differing Statistical Assumptions, Fred J. Young, R. David Hammer, Jon M. Maatta

Conference on Applied Statistics in Agriculture

Agricultural soil management is becoming increasingly precise as technology advances and as environmental concerns increase. Soil surveys are a readily available source of soils information, but soil properties are reported as generalized values or generic ranges. A need exists to define the central tendencies of soil properties in a rigorous, quantified fashion. Statistically, the central tendency is best expressed as confidence intervals about means or medians. Transect sampling was used to collect data on soil properties within a soil survey map unit. Key questions for data analysis include assumptions of independence within transects and normality. The choice of statistical method …

A Markov Chain Model To Assess Resistance Of Cattle To Horn Flies, Edward Gbur, C. Dayton Steelman

Conference on Applied Statistics in Agriculture

The horn fly is an economically important external permanent parasite of cattle. As part of a research project focused on alternatives to chemical control of the horn fly, a study was conducted to determine the degree of innate resistance of individual cattle to the horn fly. A fly resistant cow was defined as one whose horn fly counts were in the lower quartile of the weekly fly count distributions for a herd more often than would be expected by chance. A Markov chain model was formulated and a small sample test for fly resistance was developed. The model and procedure …

Statistical Analysis Of Genotype-By-Environment Interaction Using The Ammi Model And Stability Estimates, Bahman Shafii, William J. Price

Conference on Applied Statistics in Agriculture

Understanding the implication of genotype-by-environment (GE) interaction structure is an important consideration in plant breeding programs. A significant GE interaction for a quantitative trait such as yield can seriously limit efforts in selecting superior genotypes for both new crop introduction and improved cultivar development. Traditional statistical analyses of yield trials provide little or no insight into the particular pattern or structure of the GE interaction. The Additive Main Effects and Multiplicative Interaction (AMMI) statistical model incorporates both additive and multiplicative components of the two-way data structure which can account more effectively for the underlying interaction patterns. Integrating results obtained from …

Utilization Of The Line-Intercept Method To Estimate The Coverage, Density, And Average Length Of Row Skips In Cotton And Other Row Crops, Jeffrey L. Willers, Sreenivasa R. Yatham, Michael R. Williams, Dennis C. Akins

Conference on Applied Statistics in Agriculture

In row crops, a skip is a length of row within the drill where the crop has failed to establish. If the number of skips and their mean length per acre becomes too high, then considerable losses in crop yield occur. Frequently, farmers are faced with the decision to replant a crop which has row skips. To make the best decision, reliable estimates of the stand loss due to skips must be available. In making this decision, three parameters are useful: the percent of the area per acre that is skipped, the number of individual skips (that is, density) per …

Prevalence Rate Differences Based On Herdmate Comparisons, Jerome M. Sacks, Randall C. Cutlip, Amy L. Weaver, Howard D. Lehmkuhl

Conference on Applied Statistics in Agriculture

A non-random survey of ovine progressive pneumonia (OPP) seropositive prevalence rates among 16,827 sheep in 29 states in the United states revealed large breed differences, a higher prevalence rate among older sheep and an unexplainable female rate that was more that three times the male rate. The herdmate comparison procedure, successfully used in evaluating dairy bulls, was adapted to compare the prevalence of a breed to the rate of its herdmates within herds. Likewise, sex and age differences in OPP prevalence were compared within herds that contained animals of both sexes and several ages. Using herdmate comparisons, breed and age …

Studying Herbicide Resistance Using Treatment Area Dynamics Model, Agam N. Sinha, Dale L. Shaner

Conference on Applied Statistics in Agriculture

Repeated use of a herbicide or herbicides with the same mode of action on a particular crop over a number of years may cause the selection of herbicide resistant weed populations. As a result effective weed control is lost which can seriously affect crop yield and quality. The selection of herbicide resistant weed populations is a concern not only for crop-growers, but also the manufacturers of the affected herbicides. In the present paper a two-step procedure is developed to identify the herbicide resistant activity in a particular crop growing region by estimating the resistant areas (in acres/hectares) in a given …

Co-Effect Analysis Of Variance: A New Method For Unbalanced Data, Andre Plante

Conference on Applied Statistics in Agriculture

For fixed-effect models one can always, according to the Gauss-Markov Theorem, uniquely determine independent variables called source identifiers, each corresponding to a source of variation. When linearly combined, source identifiers can generate all possible expected values for the response variable. The co-effect method uses regression of the response variable on source identifiers. Corresponding regression coefficients are, by definition, unbiased estimates of co-effects, and satisfy the same restrictions as those imposed on main effects and interaction effects in standard analysis of variance. with balanced data, co-effect analysis gives results identical to those of the standard method; with unbalanced data, however, results …

Beyond Linearity And Independence, J. Stuart Hunter

Conference on Applied Statistics in Agriculture

This brief lecture discusses statistical problems associated with postulating and fitting models in engineering and the sciences. Particular emphasis is placed on the two-model problem: the employment of both deterministic and stochastic components within a model. Further, the use of empirical versus theoretical models on the part of both statisticians and experimenters is examined.

Editor's Preface, Table Of Contents, And List Of Attendees, George A. Milliken

Conference on Applied Statistics in Agriculture

These proceedings contain papers presented at the fourth annual Kansas State University Conference on Applied Statistics in Agriculture, held in Manhattan, Kansas, April 26 through 28, 1992.

Optimization In Chemical Kinetics, Arthur T. Benjamin, Gordon J. Hogenson '92

All HMC Faculty Publications and Research

No abstract provided in this article.

Inside The Quiet Revolution In Products Liability, Theodore Eisenberg, James A. Henderson Jr.

Cornell Law Faculty Publications

"A bullet in the head of products liability reform." Thus did a lobbyist orally characterize our article in this law review, The Quiet Revolution in Products Liability, describing declining plaintiff success in products liability cases in the 1980s. From the coverage and criticism the Quiet Revolution received around the country and around the world, the trends we discovered struck many as surprising enough to be newsworthy and others as sufficiently threatening to warrant a special response. Products liability's sustained presence on state and federal legislative agendas warrants continuing and expanding the study begun in the Quiet Revolution.

This …

A Progressive Disease Model For Doubly-Censred Bivariate Survival Data That Accommodates Covariate Information, Hilmi F. Yahya

Dissertations

A model for the natural history of a progressive disease is developed. The model has three disease states and can be expressed as the joint distribution of two survival random variables.

Covariate information is incorporated into the model using the proportional hazards model for the marginal distributions. The model will also accommodate data with observations which are censored on one or both of the survival random variables.

The likelihood function for censored data is exhibited for finding the maximum likelihood estimates of the parameters and their standard errors for testing the effects of the covariates. The method used to obtain …

The Application Of A Statistical Trend Analysis Program To Ground-Water Quality Monitoring Data From Eight Western Michigan Solid Waste Landfills, Amy Decosta Lachance

Masters Theses

A statistical analysis and interpretation of ground-water chemistry data from eight landfills in Western Michigan was performed. Data were collected over approximately the past ten years, pursuant to the requirements of Michigan's Solid Waste Management Act. A statistical regression model was used to reduce the data to identifiable trends and estimated magnitudes. These results were analyzed with respect to each landfill's characteristics and hydrogeological setting. Comparisons were made concerning the landfills' relative potential for environmental harm. Also, the effectiveness and applicability of this model to the analysis of ground-water monitoring data was assessed.

It was concluded that this analysis and …

A Binomial Test Of Model Fit, John Fraas, Isadore Newman

John W. Fraas

No abstract provided.

Singular Ergodic Control For Multidimensional Gaussian Processes, J. L. Menaldi, M. Robin, M. I. Taksar

Mathematics Faculty Research Publications

A multidimensional Wiener process is controlled by an additive process of bounded variation. A convex nonnegative function measures the cost associated with the position of the state process, and the cost of controlling is proportional to the displacement induced. We minimize a limiting time-average expected (ergodic) criterion. Under reasonable assumptions, we prove that the optimal discounted cost converges to the optimal ergodic cost. Moreover, under some additional conditions there exists a convex Lipschitz continuous function solution to the corresponding Hamilton-Jacobi-Bellman equation which provides an optimal stationary feedback control.

Book Review, Thomas G. Field Jr.

RISK: Health, Safety & Environment (1990-2002)

Review of the following book: THOMAS GILOVICH, How WE KNOW WHAT ISN'T SO: THE FALLIABILITY OF REASON IN EVERYDAY LIFE. (The Free Press 1991) [216 pp.] Index, notes. CIP: 90-26727; ISBN: 0-02-911705-4. [Cloth $19.95. 866 Third Ave. New York, NY 10022.]

Transformation Of Combat Data In Support Of Battle Trace, Hyoung-Kyu Choi

Theses and Dissertations

The purpose of this study was to find an appropriate way of characterizing battle data as a function of time. This study was initially designed to remove the numerical instability problem cited in Barr's battle trace methodology as suggested by TRAC-MTRY. The research focused on the instability problem and identifying/recommending a technique that improved the efficiency of computation, and enhanced an analyst's ability to meaningfully interpret the battle trace. Two Lanchester's Square Law based methodologies are introduced and analyzed. The results of this analysis indicate that the battle trace of a constant value generated by Lanchester's Square Law integration seemed …

A Sensitivity Analysis Of Circular Error Probable Approximation Techniques, Peter Puhek

Theses and Dissertations

Several algebraic CEP estimates models were examined in this study. Each assumes that the crossrange and downrange miss distances of the sample data follow a bivariate normal distribution. The analysis determined the sensitivities of these models to changes in the parameters of sample size, bias, correlation, and ellipticity. The accuracy of each model is expressed in terms of relative error, and the parameter regions in which a certain method dominated as the most accurate were noted. In general, it was found that bias was the most significant parameter in determining the best CEP method. A simple method, based on the …

Confidence Interval Estimation For Output Of Discrete-Event Simulations Using The Kalman Filter, Randall B. Howard

Theses and Dissertations

Discrete-event simulation is computer modeling of stochastic, dynamic systems. The Kalman filter is a Bayesian stochastic estimation algorithm. Because of the correlated nature of simulation output, it is difficult to apply the methods of classical statistics directly when constructing confidence intervals of discrete-event simulation parameters. Through the determination of a dynamics equation and application of the Kalman filter to simulation output data, three new confidence interval construction techniques have been developed. One technique obtains an estimate of the mean value and its associated variance from an estimated Kalman filter. The second technique utilizes Multiple Model Adaptive Estimation (MMAE) techniques to …

Multilayer Perceptrons For Classification, Lisa M. Belue

Theses and Dissertations

Techniques for training, testing, and validating multilayer perceptrons are thoroughly examined. Results obtained using perceptrons are compared and contrasted with two multivariate discriminant analysis techniques- logistic regression and k neighbor. Methods for determining significant input features are investigated and a procedure for examining the confidence to place in the significance of these features is developed. Procedures to evaluate the applicability of high-order feature inputs are examined. These methods and procedures are applied to two very different applications. The first application concerns the prediction of Air Force pilot retention/separation rates for input to force projection models. The second application concerns the …

Boundedness And Periodic Solutions In Infinite Delay Systems, Roger H. Hering

Mathematics and Statistics Faculty Research & Creative Works

Liapunov methods are used to give conditions ensuring that solutions of infinite delay equations are uniformly bounded and uniformly ultimately bounded with respect to unbounded (Cg) initial function spaces; and the connection to proving existence of periodic solutions is examined. Several examples illustrate the application of these results, especially to integrodifferential equations. © 1992.

Fixed Point Theorems For D-Complete Topological Spaces I, Troy L. Hicks

Mathematics and Statistics Faculty Research & Creative Works

Generalizations of Banach's fixed point theorem are proved for a large class of non-metric spaces. These include d-complete symmetric (semi-metric) spaces and complete quasi-metric spaces. The distance function used need not be symmetric and need not satisfy the triangular inequality. © 1992, Hindawi Publishing Corporation. All rights reserved.

Prediction Intervals, Based On Ranges And Waiting Times, For An Exponential Distribution, Laura Colangelo, Jagdish K. Patel

Mathematics and Statistics Faculty Research & Creative Works

This article contains two prediction intervals applicable to a 2-parameter as well as a 1-parameter exponential distribution. One can be used to predict a future sample range on the basis of an observed sample range. Appropriate prediction factors are tabulated. The other can be used to predict a waiting time between two future successive failures on the basis of an observed waiting time between two previous successive failures. © 1992 IEEE

The Statistics Of Lotteries, Matthew Thomas Bremer

Honors Theses, 1963-2015

This project begins with the analysis of several existing lotteries in the state of Minnesota. The raw data of these lotteries are used to calculate the expected values of certain random variables in an effort to describe and compare the lotteries mathematically. Next, the different criteria that contribute to a successful lottery are described and brought together. Finally, via mathematical modeling and computer simulation, a new lottery proposal is presented with the claim that it is superior to existing lotteries from an administrative standpoint.

On The Asymptotic Behavior And Radial Symmetry Of Positive Solutions Of Semilinear Elliptic Equations In R N Ii. Radial Symmetry, Yi Li, Wei-Ming Ni

Yi Li

The main purpose of this paper is to prove Theorems 1 and 2 of the preceding paper, Part I, together with their extensions and related symmetry results. To make this part essentially self-contained, we shall apply the method developed in Section 2 to equations with radial symmetry. Combining the asymptotic behavior and the "moving plane" technique, we are then able to obtain the desired results.

On The Asymptotic Behavior And Radial Symmetry Of Positive Solutions Of Semilinear Elliptic Equations In Rn. I. Asymptotic Behavior, Yi Li, Wei-Ming Ni

Yi Li

No abstract provided.

On The Asymptotic Behavior And Radial Symmetry Of Positive Solutions Of Semilinear Elliptic Equations In Rn. I. Asymptotic Behavior, Yi Li, Wei-Ming Ni

Mathematics and Statistics Faculty Publications

No abstract provided.

On The Asymptotic Behavior And Radial Symmetry Of Positive Solutions Of Semilinear Elliptic Equations In R N Ii. Radial Symmetry, Yi Li, Wei-Ming Ni

Mathematics and Statistics Faculty Publications

The main purpose of this paper is to prove Theorems 1 and 2 of the preceding paper, Part I, together with their extensions and related symmetry results. To make this part essentially self-contained, we shall apply the method developed in Section 2 to equations with radial symmetry. Combining the asymptotic behavior and the "moving plane" technique, we are then able to obtain the desired results.