Physical Sciences and Mathematics Commons^™

On Some Optimal Tests In Finite Mixtures: Constructions And Applications., Chandranath Pal Dr.

Doctoral Theses

Mixtures of distributions are now-a-days playing very important roles in both theoretical and applied statistics. There is an abundance of real-life situations where mixture distributions are being extensively used for modelling data and drawing inference. Several books and monographs on mixtures have so far been published, e.g., Everitt and Hand (1981), Titterington et al. (1985), McLachlan and Basford (1988), McLachlan (1997) etc., which cover a wide area on different aspects of mixture distributions and their applications. The book by Titterington et al. (1985, pp. 16-21), in particular, contains a comprehensive list of references on direct applications of finite mixtures in …

Student Fact Book, Fall 2001, Twenty-Fifth Annual Edition, 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, 2001.

Student Fact Book, Fall 2001, Wright State University Lake Campus, 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 Lake Campus for Fall Quarter, 2001.

Hierarchical Modeling For Integrated Environmental Assessments, Raymond O'Connor, Deidre Mageean

University of Maine Office of Research Administration: Grant Reports

The distribution of biotic resources over large spatial extents is often a function of climate, of land-use, and of the demographics of the human population but these different classes of independent variables have different spatial scales for their action. One approach to the integration of these effects across scales is to use hierarchical models that incorporate contingencies and constraints in effects. This project seeks to develop such a modeling paradigm by use of classification and regression trees (CART). The hexagonal grid of the U.S. Environmental Protection Agency's Environmental Monitoring and Assessment Program is used as the spatial grid, with about …

Statistical Properties Of Maximum Likelihood Estimates For Accelerated Lifetime Data Under The Weibull Model, Mahmoud A. Yousef

Doctoral Dissertations

Pipe rehabilitation liners are often installed in host pipes that lie below the water table. As such, they are subjected to external hydrostatic pressure. The external pressure leads to early deformation in the liners, which could ultimately lead to its failing or buckling before its expected service lifetime is achieved. Experiments involving long term buckling behavior of liners are typically accelerated lifetime testing procedures. In an accelerated testing procedure a liner is subjected to a constant external hydrostatic pressure and observed until it fails or for a certain time, t whichever occurs first. Liners that do not fail at time …

Stochastic Comparision And Dependence Among Order Statistics,Spacing And Concomitants Of Order Statistics., Baha-Eldin Khaledi Dr.

Doctoral Theses

The simplest and the most common way of comparing two random variables is through their means and variances. It may happen that in some cases the median of X is larger than the median of Y, while the mean of X is smaller than the mean of Y. However, this confusion will not arise if the random variables are stochastically ordered. Similarly, the same may happen if one would like to compare the variability of X with that of Y based only on numerical measures of variability. Besides, these characteristics of distributions might not exist in some cases. In most …

Heckman's Methodology For Correcting Selectivity Bias : An Application To Road Crash Costs, Margaret Giles

Research outputs pre 2011

Aggregate road crash costs are traditionally determined using average costs applied to incidence figures found in Police-notified crash data. Such data only comprise a non-random sample of the true population of road crashes, the bias being due to the existence of crashes that are not notified to the Police. The traditional approach is to label the Police-notified sample as 'non-random' thereby casting a cloud over data analyses using this sample. Heckman however viewed similar problems as 'omitted variables' problems in that the exclusion of some observations in a systematic manner (so-called selectivity bias) has inadvertently introduced the need for an …

Student Fact Book, Fall 2000, Twenty-Fourth Annual Edition, 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, 2000.

Student Fact Book, Fall 2000, Wright State University Lake Campus, 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 Lake Campus for Fall Quarter, 2000.

On Logistic And Some New Discrimination Rules:Charecterizations,Inference And Application., Supratik Roy Dr.

Doctoral Theses

Introduction and Summary Consider the problem of classification of an observation into one of two specified populations. Fisher's classification rale, just as several other rules commonly used in practice, depends only on the ratio of the individual densities fi(x), i = 1,2. This led Cox (1966),/27) to model the "posterior odds" by a simple function. Specifically,Cox's logistic discrimination (LGD) rule is then based on the statistic a + 'ßx. This has the advantage that individual densities f.(x) need not be known and we only need to estimate the parameters a and B.Another advantage, which is claimed , is that the …

Performance Of Bootstrap Confidence Intervals For L-Moments And Ratios Of L-Moments., Suzanne Glass

Electronic Theses and Dissertations

L-moments are defined as linear combinations of expected values of order statistics of a variable.(Hosking 1990) L-moments are estimated from samples using functions of weighted means of order statistics. The advantages of L-moments over classical moments are: able to characterize a wider range of distributions; L-moments are more robust to the presence of outliers in the data when estimated from a sample; and L-moments are less subject to bias in estimation and approximate their asymptotic normal distribution more closely.

Hosking (1990) obtained an asymptotic result specifying the sample L-moments have a multivariate normal distribution as n approaches infinity. The standard …

Generalised Bootstrap Techniques., Singdhansu Bhusan Chatterjee Dr.

Doctoral Theses

A typical problem in statistics is as follows: there is some observable data Xn = (X1,..., Xn), and a parameter of interest θ which is related in such a way to the distribution of Xn that meaningful conclusions about θ can be drawn based on Xn. Sometimes data Xn is observed keeping the objective parameter θ in mind, at other times the parameter appears while trying to model the observed data.Once the data is observed and the parameter fixed, the questions that have to be addressed are as follows:(I) How to estimate θ from the data Xn?(II) Given an estimator …

On Measuring The Cost Of Children:The Case Of Rural Maharashtra., Manisha Chakrabarty Dr.

Doctoral Theses

In this dissertation we have attempted to measure the cost of children, which plays a crucial role in matters relating to welfare and public policy like child benefits and compensation policies of the government. The cost is measured based on the single equation as well as the systems approach using the 38th round National Sample Survey (NSS) data on household consumer expenditure for rural Maharashtra (relating to the period of January to December, 1983).The first chapter provides a brief account of the basic literature on empirical demand analysis which is relevant for welfare comparison between households. To be specific in …

Student Fact Book, Fall 1999, Twenty Third Annual Edition November 1999, 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, 1999.

Likely And Unlikely Events In International Security Affairs: An Example From The People's Republic Of China, Ibpp Editor

International Bulletin of Political Psychology

This article describes a human judgment shortfall in international security decision making based on statistical probabilities.

Engel Curve Estimation From Budget Data Relating To Short Reference Periods., Suchismita Ghosh Dr.

Doctoral Theses

The main motivation of the present dissertation is the estimation of engel elasticities of certain items of consumption after eliminating the possible effects of seasonal and other short-run fluctuations from household budget data. Indian budget data provided by the National Sample Survey Organization (NSSO), mainly relating to the 38th round (January - December, 1983), has been utilized for the study. Such data generally relate to a moving reference period of 'last 30 days' preceding the date of interview (also referred to as the last month reference period). The use of such a reference period introduces errors in observation in both …

Tennis, Geometric Progression, Probability And Basketball, Mostafa Ghandehari

Mathematics Technical Papers

The following problem about a tennis match is well—known. See Halmos [1, 2]. Consider 2n tennis players playing a single elimination match. Ask the question: what are the number of games played? The answer can be obtained in two ways. First using the geometric progression 2n-1 + 2n-2 + • • • -2+1 we find that the answer is 2n — 1. We can also explain the answer as follows: for each game played there is a loser. Thus the total number of games played is equal to the number of losers. Since there is only one winner the total …

Muyltivariate And Regression Analysis Based On The Geometry Of Data Clouds., Biman Chakraborty Dr.

Doctoral Theses

Median is a natural estimate of location of a data set, and there are several versions of inultivariate median studied in the literature, each of which is an interesting descriptive statistic for multivariate data and provides some nice geometric insights into the data cloud. One would expect that multidimensional median will be a natural estimate for the center of symmetry of a multivariate distribution. However, there is no unique concept of symmetry in multivariate problems. The center of symmetry can be defined in several ways there. For example, the d-dimensional random variable X is spherically symmetric about e €Rd if …

Student Fact Book, Fall 1998, Twenty Second Annual Edition, 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, 1998.

Statistical Characterization Of Fluvial-Deltaic Reservoirs With Archetypes, Laura L. Watkins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Optimizing the extraction of oil and other hydrocarbon products from existing sites is important. One source of hydrocarbon products is reservoirs found within sedimentary rock formations. Understanding fluid behavior within such formations can be quite useful in optimizing oil production. Fluid behavior within sedimentary formations is influenced by the bedform structure and permeabilities within the formation. Thus, we are concerned with developing a physically and statistically valid method of characterizing sedimentary rock formations. The use of archetypal analysis to generate synthetic bedforms, as well as the use of Kriging to assign permeabilities within a bedform, was explored. With these tools, …

Static Interconnection Networks And Parallel Algorithms For Efficient Problem Solving., T. Krishnan Dr.

Doctoral Theses

There is nothing more difficult to take in hand, more perilous to conduct, or more uncertain in its success, than to take the lead in the introduction of a new order of things.

Student Fact Book, Fall 1997, 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, 1997.

Forest Resource Statistics For Northern Utah, 1993, United States Department Of Agriculture, Forest Service

Forestry

About 5.2 million acres, or 25 percent, of northern Utah is forested. Fifty-two percent of this forest area is capable of producing commercial wood products and is classified as timberland. Forty-eight percent is classified as woodland, primarily pinyon-juniper. The predominant forest types on the timberland are aspen, Douglas-fir, lodgepole pine, and spruce-fir. The National Forest System manages 70 percent of the timberland; 23 percent is under private ownership, and 7 percent is under other public ownership (local, State, and other Federal). Thirteen percent of the timberland is withdrawn from commercial timber production and is in a reserved status. Most reserved …

Measuring Hotel Service Quality: Tools For Gaining The Competitive Edge, Robert C. Ford, Susan A. Bach

Hospitality Review

As the hotel industry grows more competitive, quality guest service becomes an increasingly important part of managers' responsibility measuring the quality of service delivery is facilitated when managers know what types of assessment methods are available to them. The authors present and discuss the following available measurement techniques and describe the situations where they best meet the needs of hotel managers: management observation, employee feedback programs, comment cards, mailed surveys, personal and telephone interviews, focus groups, and mystery shopping.

Student Fact Book, Fall 1996, 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, 1996.

The Importance Of Analyzing Longitudinal Data In A Formative Evaluation Process: Applying Statistical Quality Control Techniques, John Fraas, Isadore Newman

John W. Fraas

No abstract provided.

Detecting Trends And Patterns In Reliability Data Over Time Using Exponentially Weighted Moving-Averages, Harry F. Martz, Paul H. Kvam

Department of Math & Statistics Faculty Publications

A simple, easy-to-use graphical method is presented for use in determining if there is any statistically significant trend or pattern over time in an underlying Poisson event rate of occurrence or binomial failure on demand probability. The method is based on the combined use of both an exponentially weighted moving-average (EWMA) and a Shewhart chart. Two nuclear power plant examples are introduced and used to illustrate the method. The false alarm probability and power when using the combined procedure are also determined for both cases using Monte Carlo simulation. The results indicate that the combined procedure is quite effective in …

Student Fact Book, Fall 1995, 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, 1995.

Asymptotic Properties Of Posterior Distributions And Study Of Some Nonregular Cases., Subhashis Ghosal Dr.

Doctoral Theses

The asymptotic approach to statistical estimation is frequently adopted be cause of ita general applicability and relative simplicity. The modern study of asymptotic theory, initiated in Le Cam (1953), has undergone a vigorous devel- opment through the classic works of Le Cam, Hájek, Bahadur, Ibragimov and Has'minskii (Khas'minskii), Bickel, Pfanzagl, Millar and many other scholars; see Le Cam (1986), Le Cam and Yang (1990), Ibragimov and Has'minskii (1981) and the review article by Ghosh (1985) for an account of this development.Most of the results in asymptotic theory of estimation are obtained under the classical Cramér-Rao type regularity conditions or their …

Significant Differences: The Construction Of Knowledge, Objectivity, And Dominance, Donna M. Hughes Dr.

Donna M. Hughes