Statistical Models Commons^™

Poicen.Sas : Censored Poisson Regression, Joseph Hilbe, Gordon Johnston

Joseph M Hilbe

SAS Macro to estimate censored Poisson data, using method of Hilbe. See Hilbe, Joseph M (2011), Negative Binomial Regression, 2nd ed (Cambridge University Press)

Groundwater Model Parameter Estimation Using Response Surface Methodology, Richard M. Cotman

Theses and Dissertations

This thesis examined the use of response surface methodology (RSM) to estimate the parameters of a finite-element groundwater model. An existing two-dimensional, steady-state flow model of a fractured carbonate groundwater system in southwestern Ohio served as the calibration target data set. A Plackett-Burman screening design showed that only four of the ten hydraulic conductivity zones significantly contributed to the output of the finite-element model. Also, the effective porosity parameter did not significantly affect the model's output. Using only the four significant hydraulic conductivity parameters; four two-level, four-factor designed experiments were conducted to exploit the first-order response surface defined by a …

Comparing Traditional Statistical Models With Neural Network Models: The Case Of The Relation Of Human Performance Factors To The Outcomes Of Military Combat, William Oliver Hedgepeth

Engineering Management & Systems Engineering Theses & Dissertations

Statistics and neural networks are analytical methods used to learn about observed experience. Both the statistician and neural network researcher develop and analyze data sets, draw relevant conclusions, and validate the conclusions. They also share in the challenge of creating accurate predictions of future events with noisy data.

Both analytical methods are investigated. This is accomplished by examining the veridicality of both with real system data. The real system used in this project is a database of 400 years of historical military combat. The relationships among the variables represented in this database are recognized as being hypercomplex and nonlinear.

The …

Estimating Groundwater Flow Parameters Using Response Surface Methodology, Leo C. Adams

Theses and Dissertations

This thesis examined the use of response surface methodology RSM as a parameter estimation technique in the field of groundwater flow modeling. Using RSM, an attempt was made to calibrate three hydraulic parameters porosity, transverse permeability, and rate of recharge of an existing two- dimensional, steady-state flow model. The model simulated groundwater flow for a portion of landfill 10 located on Wright-Patterson Air Force Base, Ohio. The model had previously been calibrated by graphical matching observed water-levels to predicted water-levels. Using the parameter values from the earlier calibration effort as a starting point, a central composite design was developed and …

Derivation Of A Scaled Binomial As An Instance Of A General Discrete Exponential Distribution, Joseph Hilbe

Joseph M Hilbe

No abstract provided.

A Bayesian Approach To Additive Nonparametric Regression, Michael S. Smith, Robert Kohn

Michael Stanley Smith

This proceedings paper was the first to suggest using a Gaussian g-prior combined with a point mass to undertake Bayesian variable selection in a Gaussian linear regression model. It also was the first to suggest integrating out the regression parameters and variance in closed form, resulting in an efficient Gibbs sampling scheme. The idea was applied to estimate regression functions in an additive model by using a linear basis expansion for each component function in an additive model. The conference proceeding was eventually published in a slightly tighter form in Journal of Econometrics (1996).

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 …

Generalized Linear Models: Software Implementation And The Structure Of A General Power-Link Based Glm Algorithm, Joseph Hilbe

Joseph M Hilbe

Generalized linear modeling (GLM) is currently undergoing a renaissance. The number of software packages offering GLM capability grows each year and as a partial consequence one finds an increased number of research endeavors being modeled using GLM methodology. On the other hand, there have likewise been an increasing number of requests to vendors by users of statistical packages to include GLM facilities amid other offerings. The overall effect has been a near 300 percent increase in GLM programs over the past four years.

I shall discuss the nature of generalized linear models followed by an examination of how they have …

Polygon Explorer For Massachusetts Data: Initial Report, Center For Economic Development

Center for Economic Development Technical Reports

Polygon Explorer is a program written for Macintosh computers that links data stored in standard spreadsheet formats with a geographic database. It differs from similar programs such as MapInfo and ArcView in that it provides a statistical visualization capability in the form of bar charts, histograms, scatterplots, and other views, and further these views are linked to one another so that any action in one view results highlighting in other views.

Polygon Explorer was initially developed with the support of funding from the Massachusetts Agricultural Experiment Station, and parts of a donation form the Environmental Systems Research Institute and a …

Log-Negative Binomial Regression As A Generalized Linear Model, Joseph Hilbe

Joseph M Hilbe

The negative binomial (NB) is a member of the exponential family of discrete probability distributions. The nature of the distribution is itself well understood, but its contribution to regression modeling, in particular as a generalized linear model (GLM), has not been appreciated. The mathematical properties of the negative binomial are derived and GLM algorithms are developed for both the canonical and log form. Geometric regression is seen as an instance of the NB. The log forms of both may be effectively used to model types of POisson-overdispersed count data. A GLM-type algorithm is created for a general log-negative binomial regression …

An In Vitro Study Comparing The Conventional Step-Back Instrumentation Technique To A Combination Step-Back/Ultrasonic Technique, James A. Eberhardt

Loma Linda University Electronic Theses, Dissertations & Projects

Cleaning and shaping the root canal system is an important phase of endodontic therapy, and must be performed thoroughly and completely if successful root canal therapy is to be expected. A number of investigators have compared different methods of cleaning and shaping of the root canal system. The purpose of this study was to compare the effectiveness of the conventional step-back technique with that of a combination step-back/ultrasonic technique. This combination technique is a modification of the conventional step-back technique using an ultrasonic instrument alternately with hand instrumentation. Utilizing 40 canals from extracted human mandibular molar teeth with a curvature …

Dysfunctional Attitudes, Life Stress And Coping Processes, Deborah Desalliers

Loma Linda University Electronic Theses, Dissertations & Projects

The findings of recent investigations earmarked chronic daily stressors as being highly related to stress levels. In addition, researchers are promoting a more integrative model of stress. The stress response is no longer thought of in strictly linear terms, i.e. an event causes stress. Rather, cognitive factors, existing within the human mind itself, strongly influence our coping processes and the chronic stress we experience.

Canonical correlation analysis was used to study how dysfunctional attitudes, a negative cognitive factor, were related to individuals' daily hassles and coping processes. An increase in dysfunctional attitudes was found to correspond to an increase in …

Modeling Mass Transport In Aquifers: The Distributed Source Problem, Sergio E. Serrano

KWRRI Research Reports

This report presents a new methodology to model the time and space evolution of groundwater variables in a system of aquifers when certain components of the model, such as the geohydrologic information, the boundary conditions, the magnitude and variability of the sources or physical parameters are uncertain and defined in stochastic terms. This facilitates a more realistic statistical representation of groundwater flow and groundwater pollution forecasting for either the saturated or the unsaturated zone. The method is based on applications of modern mathematics to the solution of the resulting stochastic transport equations. This procedure exhibits considerable advantages over the existing …

Regression Models For Bivariate Binary Responses, Juni Palmgren

UW Biostatistics Working Paper Series

We discuss maximum likelihood inference for the bivariate logistic model, specified in terms of the marginal logits and the log odds ratio. Using the exponential family nonlinear model formulation the model fitting can be done in GLIM. The procedure is illustrated by modelling survival of unilateral and bilateral total hip arthroplasties as function of patient specific and hip specific covariates. We compare maximum likelihood inference with inference obtained from solving likelihood equations under the assumption of within block independence and using robust standard errors for the estimates. Simulations indicate that the latter procedure is effcient for block specific covariates but …

Direct Tests Of The Rational Expectations Hypothesis: A Study Of Italian Entrepreneurs’ Inflationary Expectations (1980-1988), Claudio Lupi

Claudio Lupi

The primary concern of this paper is to test the rational expectations hypothesis for Italian entrepreneurs' inflationary expectations between 1980 and 1988 using monthly observed expectations. Particular care is devoted to analyzing the problems arising when multiperiod expectations and a nonwhite noise measurement error in the expectations series are considered. The empirical analysis is carried out using cross correlations on ARIMA residuals and transfer function models. This technique seems to be particularly appealing for rationality testing.

Improved Methods And Guidelines For Modeling Stormwater Runoff From Surface Coal Mined Lands, Michael E. Meadows, George E. Blandford

KWRRI Research Reports

The investgations, developments and guidelines for several hydrologic modeling strategies are presented. Investigations were conducted to determine appropriate event curve numbers for surface mined disturbed watersheds; and performance of four synthetic unit hydrograph models (SCS curvilinear, SCS single triangle, Williams and TVA double triangle) on 38 USDA experimental watersheds in 14 physiographic provinces using in excess of 270 events. A second test using only the SCS curvilinear unit hydrograph on 11 small watersheds and 48 events was conducted to investigate the excess rainfall pattern simulated with the curve number model. A procedure for developing a unit hydrograph using the time …

Modeling Surface And Subsurface Stormflow On Steeply-Sloping Forested Watersheds, Patrick G. Sloan, Ian D. Moore, George B. Coltharp, Joseph D. Eigel

KWRRI Research Reports

A simple conceptual rainfall-runoff model, based on the variable source area concept, was developed for predicting runoff from small, steep-sloped, forested Appalachian watersheds. Tests of the model showed that the predicted and observed daily discharges were in good agreement. The results demonstrate the ability of the model to simulate the "flashy" hydrologic behavior of these watersheds.

Five subsurface flow models were evaluated by application to existing data measured at Coweeta on a reconstructed homogeneous forest soil. The five models were: Nieber 's 2-D and 1-D finite element models (based on Richards' equation), the kinematic wave equation, and two simple storage …

The Effect Of Post-Hospital Nursing Intervention On Success In Breastfeeding, Melinda Hoskins

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to compare the proportion of women in the experimental group who had a successful breastfeeding experience following post-discharge nursing intervention with the proportion of women in the control group who had a successful breastfeeding experience without nursing intervention. Criteria defining success in breastfeeding were established before the study. Chi-square analysis was used to test for significance with the preset level of significance being α = 0.05. The sample comprised 25 mother-infant dyads with 12 in the experimental group and 13 in the control group. Both groups were similar in type of delivery (spontaneous or …

The Effect Of A Values Clarification Strategy On The Smoking Behavior Of Pregnant Women, Jean Eiber

Loma Linda University Electronic Theses, Dissertations & Projects

The null hypothesis of this study stated that there would be no significant difference (α=.05) in the change in smoking behavior following a teaching intervention to discourage smoking in pregnant women between those who completed a values clarifying strategy prior to the intervention and those who did not. Forty subjects were randomly assigned 20 to an experimental group and 20 to a control group. Both groups completed a pretest questionnaire concerning demographic data and smoking behavior. Information regarding the adverse effects on the fetus and on the developing child of smoking was presented to each subject by the researcher. The …

The Maine Coast, A Statistical Source, Maine Coastal Program

Maine Collection

The Maine Coast, A Statistical Source

Maine Coastal Program, Natural Resource Planning Division, Maine State Planning Office , Augusta, Maine

First Printing June 1978 - Second Printing September 1978

Contents: Preface / Introduction / Chapter 1 - Demography / Chapter 2 - Land Use and Taxation / Chapter 3 - Economy / Chapter 4 - Housing / Chapter 5 - Transportation / Chapter 6 - Education / Chapter 7 - Recreation / Chapter 8 - Social Services / Chapter 9 - Natural Resources / References / Index

Improving On The Contingent Fee, Kevin M. Clermont, John D. Currivan

Cornell Law Faculty Publications

Two basic fees--contingent and hourly--dominate the variety of fees that lawyers charge clients for pursuing damage claims. Each of these two types has its advantages; each is plagued with substantial disadvantages. This Article proposes a new type of fee, one that preserves the respective advantages of the two present fees while minimizing their distinct disadvantages.

In essence, the proposed fee calls for the payment, on a contingent basis, of an amount computed by adding one component tied to hours worked and another component linked to amount recovered. The preferability and feasibility of this proposed fee argue for the abolishment, or …

A Statistical Approach To The Study Of The Ecosystems Of Seven Ponds In East-Central Illinois, Gregory Lee Orr

Masters Theses

Gross primary productivity, heterotrophic bacterial numbers, and net phytoplankton densities of seven ponds in Coles County, Illinois, were studied in relation to physical, chemical, and biological habitat variables (light intensity and duration, turbidity, water temperature, pH, dissolved oxygen, sulfur, nitrogen, phosphorus, production, bacteria, and phytoplankton). Ten observations were made for each pond (except where otherwise noted) from 17 June through 25 August 1974. Stepwise multiple linear regression analyses of the data were used in order to determine those environmental factors which were important in predicting (i.e., significantly correlated with) bacterial and phytoplankton densities, and production. A multiple linear regression equation …

Multiregional Interactions Between Energy And Transportation, Karen R. Polenske

Applications

Because of the number and complexity of the issues that will determine the use of coal by the electric-generating plants, an important asset of policy makers will be the availability of a method of analysis that allows for quick studies of many different combinations of assumptions and policies. The present prototype study is designed to show how the multiregional input-output model can be used to investigate each different assumption and policy alternative. For this paper, the analysis has necessarily been restricted to two issues. First, the results of using regional rather than national technologies in the model are assessed. This …

Some Aspects Of Ties In Wilcoxon Signed Ranks, Kathleen M. Keenan

Journal of the Minnesota Academy of Science

Assuming basic principles of statistical inference, the signed rank and rank sum hypothesis testing procedures of Wilcoxon ore reviewed briefly and illustrated. Some recent literature of interest is cited. The problem of ranking tied data is considered, and the effect of ties on the distribution of the signed rank statistic is examined.

The Pseudo-Problem Of Induction, Joseph Hilbe

Joseph M Hilbe

Paper I delivered at the IVth International Congress for Logic, Methodology, and Philosophy of Science held in Bucharest, Romania in 1971.

Opset Program For Computerized Selection Of Watershed Parameter Values For The Stanford Watershed Model, Earnest Yuan-Shang Liou, L. Douglas James

KWRRI Research Reports

The advent of high-speed electronic computer made it possible to model complex hydrologic processes by mathematical expressions and thereby simulate streamflows from climatological data. The most widely used program is the Stanford Watershed Model, a digital parametric model of the land phase of the hydrologic cycle based on moisture accounting processes. It can be used to simulate annual or longer flow sequences at hourly time intervals. Due to its capability of simulating historical streamflows from recorded climatological data, it has a great potential in the planning and design of water resources systems. However, widespread use of the Stanford Watershed Model …

A Cephalometric Study Of The Face And Dentition Of Several Contemporary Western United States And Alaskan Eskimo Groups, Robert C. Parkard

Loma Linda University Electronic Theses, Dissertations & Projects

A total of 223 cephalometric radiographs selected from six contemporary western United States and Alaskans native groups were analyzed by use of the Bjork cephalometric analysis. Those native groups selected were the Eskimos, Apaches, Navajos, Papagos, Pimas and Mayos. Approximately thirty to forty natives from each group were used in the study with ages ranging from thirteen to thirty-five years. The majority were in the fifteen to twenty year age range.

All data was submitted to various statistical analyses to establish a mean, standard deviation, and other relevant values for each of the native groups and to compare these values …

Simulation Of Mathematical Models In Genetic Analysis, Dinesh Govindal Patel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In recent years a new field of statistics has become of importance in many branches of experimental science. This is the Monte Carlo Method, so called because it is based on simulation of stochastic processes. By stochastic process, it is meant some possible physical process in the real world that has some random or stochastic element in its structure. This is the subject which may appropriately be called the dynamic part of statistics or the statistics of "change," in contrast with the static statistical problems which have so far been the more systematically studied. Many obvious examples of such processes …