bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Impact of Private Insurance Coverage on Veterans' Use of VA Care: Insurance and Selection Effects
Authors: Shen Yujing , Hendricks Ann , Wang Fenghua , Gardner John , Kazis Lewis E. 
Published: June 2007

Objective. To examine private insurance coverage and its impact on use of Veterans Health Administration (VA) care among VA enrollees without Medicare coverage.Data Sources. The 1999 National Health Survey of Veteran Enrollees merged with VA administrative data, with other information drawn from American Hospital Association data and the Area Resource File.Study Design. We modeled VA enrollees' decision of having private insurance coverage and its impact on use of VA care controlling for sociodemographic information, patients' health status, VA priority status and access to VA and non‐VA alternatives. We estimated the true impact of insurance on the use of VA care by teasing out potential selection bias. Bias came from two sources: a security selection effect (sicker enrollees purchase private insurance for extra security and use more VA and non‐VA care) and a preference selection effect (VA enrollees who prefer non‐VA care may purchase private insurance and use less VA care).Principal Findings. VA enrollees with private insurance coverage were less likely to use VA care. Security selection dominated preference selection and naïve models that did not control for selection effects consistently underestimated the insurance effect.Conclusions. Our results indicate that prior research, which has not controlled for insurance selection effects, may have underestimated the potential impact of any private insurance policy change, which may in turn affect VA enrollees' private insurance coverage and consequently their use of VA care. From the decline in private insurance coverage from 1999 to 2002, we projected an increase of 29,400 patients and 158 million dollars for VA health care services.
Is There a Role for Bisphosphonates in Chronic Kidney Disease?
Authors: Miller Paul D. 
Published: June 2007

AbstractPatients with stage 5 chronic kidney disease (CKD) including those on dialysis can and do develop osteoporosis. They also develop a wide range of other metabolic bone diseases that may look like osteoporosis when it is defined by either the World Health Organization bone mineral density (BMD) criteria or by the development of fragility fractures. Those dialysis patients with osteoporosis that is due to gonadal hormone deficiency such as postmenopausal osteoporosis, glucocorticoid‐induced osteoporosis, or male osteoporosis may benefit from the administration of bisphosphonates (BPs). The challenges lie in the diagnosis of osteoporosis in this population where adynamic, osteomalacic, hyperparathyroid, or aluminum bone disease are also prevalent, with concommitant low BMD and low trauma fractures, but where BPs may be contraindicated. The only secure means to diagnose osteoporosis in this patient population is by quantitative bone histomorphometry demonstrating low trabecular bone volume and disrupted microarchitecture. Once the diagnosis of osteoporosis is established, BPs should be considered for a well‐defined brief period of time (e.g., 2–3 years), even though there is no evidence for a fracture reduction benefit in this population. If a BP is chosen there may be a need for dose adjustment or slower infusion rates (for the intravenous formulations), as a greater bone retention may occur for these renally cleared agents. While it is unknown what consequences could develop from increased bone retention in patients with little renal function, data are needed if more bone retention of BP might lead to a greater risk of the development of adynamic bone disease and lower bone strength. More data are needed to define the risks and benefits of BPs in patients with stage 5 CKD.
The Acute Cardiac Effects of Dialysis
Authors: Selby Nicholas M. , McIntyre Christopher W. 
Published: June 2007

AbstractIt is well recognized that the procedure of hemodialysis is associated with significant changes in blood pressure and systemic hemodynamics; 20–30% of treatments are complicated by intradialytic hypotension (IDH). There are now an increasing number of studies using electrocardiographic, isotopic and echocardiographic techniques that show that subclinical myocardial ischemia occurs during dialysis. This concept is supported by some studies showing that dialysis can induce acute rises in troponins and creatinine kinase MB, although this has not been found by all authors. Some of this controversy may at least in part be due to the collection of blood samples immediately postdialysis, which is likely to be too early to reliably detect dialysis‐induced elevations of cardiac enzymes. Cardiovascular death is the biggest single cause of mortality in dialysis patients and of this sudden death comprises the largest proportion. As such, there is a large body of evidence examining whether dialysis is pro‐arrhythmogenic. It is clear that dialysis can increase QTc interval and QT dispersion and is capable of inducing arrhythmias on Holter monitoring, likely due to the interaction of multiple factors, some of which prime for the development of arrhythmias (particularly the presence of preexisting cardiac disease), and some of which act as triggers. However, the link between these electrocardiographic alterations and sudden death is relatively poorly studied. This review summarizes the available literature regarding the acute cardiac effects of dialysis in relation to the above, and discusses how these acute changes may contribute to the genesis of uremic cardiomyopathy and longer term cardiac outcomes.
Effects of Distraction Versus Spatial Discrimination on Laser‐Evoked Potentials in Migraine
Authors: de Tommaso Marina , Baumgartner Ulf , Sardaro Michele , Difruscolo Olimpia , Serpino Claudia , Treede Rolf‐Detlef 
Published: June 2007

Objectives.— To evaluate whether migraine patients exhibit less inhibition to painful stimuli when distracted from pain as compared to healthy subjects, testing the spatial discrimination of painful stimuli, the performance during the mental arithmetic task used to contrast the discrimination performance and the behavior of N1 and N2‐P2 laser‐evoked potentials (LEPs) amplitudes during spatial discrimination and during distraction.Methods.— Eight migraine patients and 8 healthy controls were examined. During repetitive series of painful laser stimulation of the hand, they had to (1) perform a spatial discrimination task, contrasted by (2) a mental arithmetic task that served as distraction.Results.— Patients made 50% to 100% more mistakes than controls in the spatial discrimination task (P < .001) as well as during mental arithmetic (P < .05). Whereas healthy subjects showed a marked decrease of the LEP vertex potential amplitudes during distraction compared to the discrimination task, no such attenuation of LEPs was seen in migraine patients (group × task interaction, P < .05). N1 amplitude exhibited a left‐hemisphere dominance in both groups, significantly smaller amplitude in migraine patients, but no significant task modulation.Conclusion.— Migraine patients exhibited reduced inhibition by attentional modulation of pain processing, accompanied by impaired spatial discrimination of painful stimuli.
A Randomized, Controlled Trial of tai chi for the Prevention of Falls: The Central Sydney tai chi Trial
Authors: Voukelatos Alexander , Cumming Robert G. , Lord Stephen R. , Rissel Chris 
Published: June 2007

OBJECTIVES: To determine the effectiveness of a 16‐week community‐based tai chi program in reducing falls and improving balance in people aged 60 and older.DESIGN: Randomized, controlled trial with waiting list control group.SETTING: Community in Sydney, Australia.PARTICIPANTS: Seven hundred two relatively healthy community‐dwelling people aged 60 and older (mean age 69).INTERVENTION: Sixteen‐week program of community‐based tai chi classes of 1 hour duration per week.MEASUREMENTS: Falls during 16 and 24 weeks of follow‐up were assessed using a calendar method. Balance was measured at baseline and 16‐week follow‐up using six balance tests.RESULTS: Falls were less frequent in the tai chi group than in the control group. Using Cox regression and time to first fall, the hazard ratio after 16 weeks was 0.72 (95% confidence interval (CI)=0.51–1.01, P=.06), and after 24 weeks it was 0.67 (95% CI=0.49–0.93, P=.02). There was no difference in the percentage of participants who had one or more falls. There were statistically significant differences in changes in balance favoring the tai chi group on five of six balance tests.CONCLUSION: Participation in once per week tai chi classes for 16 weeks can prevent falls in relatively healthy community‐dwelling older people.
OPTIMALITY OF INDEPENDENT DECISION‐MAKING FOR TWO INDEPENDENT RISK SITUATIONS*
Authors: NETER J. , WILLIAMS C. A. , WHITMORE G. A. 
Published: June 2007

ABSTRACTThis paper investigates the optimality of making two insurance decisions independently in the expected utility framework, when the two risks under consideration are independent. It is shown that when the disutility function embodies constant risk aversion, independent decision‐making is identical to optimal joint decision‐making. When the disutility function has strictly decreasing risk aversion, joint decision‐making is always not less conservative than independent decision‐making, and the opposite holds when the disutility function has strictly increasing risk aversion. Stronger results are obtained for some particular disutility functions. Finally, some implications of these results for empirical research in utility and decision theory are considered.
DESIGN AND IMPLEMENTATION PHILOSOPHY FOR QUANTITATIVELY ORIENTED UNDERGRADUATE BUSINESS PROGRAMS
Authors: BLACK JAMES A. 
Published: June 2007

ABSTRACTWhile the quantitative content of business programs has increased over the last decade, there is still room for improvement. One of the problems facing many schools is lack of mathematical ability among students. This is particularly true in schools with open admission policies. As an alternative to high admission standards, a school may partition its student body on the basis of mathematical ability and offer different programs to each group. Initially all students would follow a non‐terminal mathematies sequence. Those performing well in this sequence would be encouraged to elect advanced courses in mathematics. A core of quantitative business courses would be provided. Quantitative programs in the functional areas of business would be built around this core. Alternative programs would be offered for non‐quantitatively oriented students.
MULTI‐ITEM INVENTORY SYSTEMS WITH AMALGAMATION OF ORDERS TO SUPPLIERS*
Authors: THOMPSON H. E. , FEDER T. L. , KRAJEWSKI L. J. 
Published: June 2007

ABSTRACTThis paper extends the analysis of the multi‐item inventory systems with amalgamation of orders to the case where there is more than one possible supplier. The problem is to assign each inventory item to an order period and a supplier such that the total inventory costs are minimized. The model is formulated as an integer programming problem which can be solved by standard linear programming techniques. In addition to providing the framework for selecting the supplier for an item, the model can include different ordering and review costs, price differentials between suppliers, quantity discounts, inventory constraints and ordering constraints. Numerical examples illustrating the use of the model are provided.
PRODUCTION FACTORS IN POLICING SERVICES*
Authors: HOFFMAN RICHARD B. 
Published: June 2007

AbstractThe demand for increased public protection has become a major public issue of our times. The usual American response of increased resources has been applied but has had less than the desired effects. This paper analyzes the existing production factors in the provision of policing services in terms of the efficiency with which these services are delivered. The efficiency analysis occurs on a number of levels: (1) the use of existing resources, (2) alternative allocation at the existing resource level, (3) alternative technologies, and (4) the tasks and services which should be undertaken. The effects and implications of exogenous changes upon crime and policing services are considered and the problems and needs for change in the production factors for policing services are presented.
INPUT COSTS OF PRODUCING UNIVERSITY DEGREES: A CASE STUDY
Authors: EWALD A. A. , KIKER B. F. 
Published: June 2007

AbstractAbstractIn this paper, we devise a cost allocation matrix and employ it to estimate the average input (net of capital) cost to the University of South Carolina of producing various degrees. The end product of our technique permits a statement of the comparative input costs of producing degrees from each of the several product (degree‐granting) divisions within the university. These cost estimates should be useful to administrators concerned with establishing tuition rates.Although our data are for a particular university, factor inputs used by this university for transmitting knowledge are taken from regional, national and international markets. Curricula for similar degrees in different universities are similar in composition. Hence, our study should have general applicability.
THE EFFECTIVE UNIT OF THE POISSON DISTRIBUTION AND DEMAND FORECASTING
Authors: RAINE JESSE E. 
Published: June 2007

AbstractThis short paper deals with some of the difficulties which have been found in applying the effective unit concept of estimating the Poisson distribution in order to forecast demand in a major industry. It points to two special cases in which the common formulation produces misleading results, discusses the frequency with which these two special cases could be expected to occur based on this one major industry, and proposes some pragmatic solutions to the problems resulting.
APPLICATIONS OF A RISK AVERSION CONCEPT
Authors: BERHOLD MARVIN 
Published: June 2007

ABSTRACTIn decision theory the concept denoted variously as “risk aversion increment” or “risk premium” has not been fully exploited, although it is neither new nor complex. In this paper we will show how the concept of the risk aversion increment can be used for developing an alternative to the explicit use of the utility function. For most people the use of a risk aversion increment provides a better conceptual reference than does the use of a utility function.To illustrate the usefulness of the concept as a basis for gaining insight into problem statements and their analysis, the following applications are developed:1) general results for the exponential utility function. 2) estimation of utility functions. 3) general results for various combinations of utility functions and probability distributions. 4) use in sequential decisions. 5) application in the theory of incentives.
SUCCESSFUL MODELS I HAVE KNOWN*
Authors: ARNOFF E. LEONARD 
Published: June 2007

ABSTRACTFormal education equips the modern decision scientist with an ample bag of mathematical tools. Among these are a wide variety of models, supplemented by techniques for creating new models and augmenting old ones. The purpose of a model, however, is not to serve only as a classroom exercise, but, rather, to represent reality in mathematical terms. Therefore, the performance of a model under real‐life conditions determines its success or failure.In this paper, the author examines the characteristics of successful models, concentrating on the potential pitfalls in both the formulation and implementation stages. Finally, the author discusses the implications of his views for business schools, especially in terms of the improvements in course requirements and teaching techniques which are needed to prepare students of quantitative methods for careers as effective decision scientists.
A STUDY OF TIMING AND WITHDRAWALS OF STUDENT ADMISSIONS APPLICATIONS*
Authors: HAUSMAN WARREN H. , SHEARER ROBERT E. 
Published: June 2007

ABSTRACTThis study explores two important characteristics of admissions applications to an M.B.A. and M.P.A. program: the timing of applications throughout the year preceding entrance, and the withdrawal rate by students whose applications have been accepted. Specifically, for the years 1961 through 1967, the aggregate patterns of timing and withdrawals (across all applications) are compared to the corresponding data for four groups of applications, ranging from low quality to high quality. (Quality is measured in terms of a first‐year predicted grade point average, and is estimated by a linear regression equation using the applicant's total ATGSB score and his undergraduate grade point average.) The results are in the expected directions: “better” students tend to apply earlier, and also have a higher tendency to withdraw after their applications have been accepted. Potential usefulness of the results in forecasting total applications and estimating withdrawal rates is explored.
An Information‐Theoretic Approach*
Authors: KERNAN JEROME B. , HAINES GEORGE H. 
Published: June 2007

ABSTRACTThis paper examines the search aspect of decision making. An experiment was conducted to assess the amount of information utilized by subjects prior to committing themselves to a choice. By construing the information environment in the form of a maze and measuring “transmitted” information according to the Shannon‐Weaver logarithmic metric, the power of subjects' search heuristics was assessed.
STAFFING SERVICE ACTIVITIES WITH WAITING LINE MODELS
Authors: PAUL ROBERT J. , STEVENS ROBERT E. 
Published: June 2007

ABSTRACTThe problem of scheduling service activities and variable tasks has traditionally been solved subjectively. The lack of objective approaches has been due to the absence of formal standards and delay costs and by the high cost of examination and measurement. Some recent developments in work measurement concepts may permit the development of more objective standards, which when used in conjunction with scientific methodology such as waiting line theory, make possible objective scheduling of the variable service type activity.The work of a salesperson in a retail store provides an example of both the variable service type activity and the waiting line problem. The manager attempts to balance the cost of service facilities (sales personnel) against the cost of a waiting line (customer ill will). The necessary data inputs for the waiting line model were obtained from field studies by means of work sampling. Computer simulation was then utilized to study various sized sales forces in an attempt to determine the most economical staff allocation.
ASSIMILATION TIME AS A FACTOR OF PERFORMANCE IN QUANTITATIVE ANALYSIS
Authors: TERSINE RICHARD J. , FLEMING RICHARD J. 
Published: June 2007

ABSTRACTThe schedule, length, and number of class meetings have tended to be dictated by tradition, space availability, and instructor convenience. A significant factor which must receive attention is the assimilation time of the student. With the increased emphasis on quantitative analysis as well as the expansion of the boundaries of course content, the ability of the student to successfully absorb and digest the material must be considered. The authors have statistically studied assimilation time as a performance factor in a mathematically‐oriented course. Their conclusions indicate that the length and number of class meetings can be modified to a degree with equifinality, but administrators and instructors should empirically verify the best mix for their specific needs.
PORTFOLIO EVALUATION & RE‐EVALUATION: AN EXPERIMENT IN SUBJECTIVE PROBABILITY, MAN‐MACHINE LEARNING AND DECISION MAKING
Authors: KROLAK PATRICK D. 
Published: June 2007

ABSTRACTIn order to bring home to management science students a proper overview of the field, the author undertakes the investigation of real world problems using the methods of systems analysis and operations research. This paper will describe the results of one such investigation. In addition to describing the classroom experiment, a model for speculative stock market investment will be developed. Finally, a simulation model for reviewing investor performance will be outlined.
SIMULATION EXPLORATION OF THE POWER OF MARGINAL REGRESSION ANALYSIS*
Authors: ELLIOTT JAN WALTER , SOELBERG PEER 
Published: June 2007

ABSTRACTIn either simple or multivariate regression models, measured coefficients represent a kind of average of co‐variant relationships implicit in the data. For time‐series data, if co‐variant relationships follow no particular pattern over the sample period, use of this average in forecasting is rational. However, if relationships among independent and dependent variables is undergoing change over time, then measured regression coefficients are likely to be poor tools for prediction. This paper is an exploratory study of this general problem area. It develops implications as to the predictive impact of the problem and offers preliminary suggestions as to a method of developing predictions under such circumstances.
A TEST FOR THE DETECTION OF A POISSON PROCESS
Authors: REINMUTH JAMES E. 
Published: June 2007

ABSTRACTA statistical test is presented to detect the presence of a Poisson input source into a queueing system. The fact that the arrival times of a Poisson input source are distributed independently and uniformly over time is used in conjunction with the central limit theorem to develop a test, based on the sum of the arrival times over a given interval of time, for the hypothesis that an input source into a queueing system is Poisson. Failure to reject this hypothesis gives one an extra degree of assurance that traditional queueing models assuming a Poisson input are applicable.
AIR QUALITY CONTROL MODEL COMBINING DATA ON MORBIDITY AND POLLUTION ABATEMENT*
Authors: KOHN ROBERT E. , BURLINGAME DONALD E. 
Published: June 2007

ABSTRACTA pollution damage function is developed, using data from a study on the sensitivity of morbidity to ambient air concentrations of individual pollutants. This function is used in a model which incorporates the costs and technology for pollution abatement in the St. Louis Airshed. A set of air quality standards is determined which minimizes morbidity subject to a given control budget constraint. The results indicate that there should be a greater reduction of the pollutants associated with stationary sources than of those characteristic of the automobile.
DEFINING THE ROLE AND ESTIMATION OF THE DISCOUNT FACTOR IN A SECURITY VALUATION MODEL
Authors: KURATANI YOSHIRO , BECHTOLD J. E. , MANTEL SAMUEL J. 
Published: June 2007

ABSTRACTIn this paper we show that a striking improvement in the explanatory power of a “dividend type” of security valuation model can be obtained by classifying companies into equivalent risk categories, estimating the discount factor for a category, and then constructing a cross‐sectional model for it. The increased homogenity of the data base improves the model's sensitivity to systematic forces, but does not sacrifice the heterogeneity of the independent variables.Assuming that the difference between the intrinsic value of a security and its market value should be zero, the authors demonstrate a method for estimating kjt, the market discount rate for the jth risk category in the tth period. The results of the estimation procedure appear to be reasonable and when used in our security valuation model they produce higher coefficients of determination (R2) than those previously published for similar models.