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Focuses on a mathematical model for exhaustion of oil. Way to estimate cumulative usage of a nonrenewable resource whose rate of use is increasing at a fixed rate; Information that the U.S. has recoverable reserves of coal that would last about 250 years; Affect of the decline of the dollar on the oil prices in U.S.

Using a disaggregated model and a three-stage least squares procedure, this paper estimates the demand for automobiles in the U.S. by size class. While the price elasticity of demand in each submarket was significantly greater than one, factors such as gasoline prices, styling changes, and demographic changes influenced each submarket differently. [ABSTRACT FROM AUTHOR]

Karl Pearson, the founder of mathematical statistics, was the leading statistical researcher from the 1890s up to about 1920. His interests were wide-ranging and so his impact on statistics in the United States was also wide-ranging. Many American researchers came to University College London to study with him. Others studied his work from afar. In the United States, Pearsonian statistics first penetrated the academic landscape in biology. This was soon followed by the fields of economics and psychology. It was not until relatively late in Pearson's career that several American mathematicians took up statistics as a serious research topic. [ABSTRACT FROM AUTHOR]

Background: Diagnosis and treatment for individuals with brain tumors during childhood involves sequelae, including abnormal weight gain. This symptom is commonly clustered with fatigue and increased risk for cardiovascular disease. Children's Oncology Group recommendations include annual surveillance of body mass index (BMI) and cardiometabolic comorbidities; however, there has been little emphasis on individualized screening early in survivorship. Purpose: The primary purpose of this paper is to describe the findings of abnormal weight gain and its correlates in a sample of young childhood brain tumor survivors during early survivorship. Design and Methods: This cross‐sectional multi‐site study included brain tumor survivors of ages 8–12 years who were less than 6 years posttreatment. Convenience sampling from two pediatric cancer centers in the southern United States was utilized. Data collected included BMI, parent report of sleep, and child report of fatigue and stress. Results: The sample (N = 21) consisted of children who had received chemotherapy, radiation treatment, and surgery for childhood brain tumor. BMI in overweight and obese categories exceeded normative samples with 38% at or above the 85th percentile. There were clinically significant relationships with fatigue, stress about weight, tumor location, cranial radiation, chemotherapy, and recurrence Practice Implications: Screening for abnormal weight gain and related factors, such as fatigue should begin early in survivorship after childhood brain tumor treatment completion with the aim of health promotion and disease prevention. Adiposity measurement techniques should be utilized in future clinical and research settings to improve assessment of cardiometabolic risk. [ABSTRACT FROM AUTHOR]

Purpose - The purpose of this paper is to develop a benchmark of performance standards for Chinese third-party logistics providers (3PLs) in the emerging market. It also intends to identify various factors that significantly affect the operational efficiency of the Chinese 3PLs and propose ways to improve the competitiveness of 3PLs. Design/methodology/approach - This paper proposes data envelopment analysis (DEA) to measure the operational efficiency of ten leading 3PLs in China, relative to prior periods and their key competitors. In particular, this paper develops both the Charnes, Cooper and Rhodes model and the Banker, Charnes and Cooper model that are designed to derive weights without being fixed in advance. It also uses step-wise regression analysis to identify factors influencing the performances of Chinese 3PLs. Findings - First, the declining efficiency within some Chinese 3PLs coincides with a steep decline in domestic transportation activities due to the SARS outbreak and the slow adaptation of state-owned enterprise into a more market-based economy. Second, the sales opportunity and the level of technical expertise are directly con-elated with the operational efficiency of 3PLs, whereas the size of 3PLs has no direct bearing on the 3PL's performance. Third, in contrast with the 3PL industry in the USA, the Chinese 3PLs tend to focus on traditional service offerings such as port management, transportation, and warehousing rather than playing the role as the integrator or the lead service provider. Originality/value - This paper is the first attempt to utilize DEA to develop performance benchmarks for 3PLs in the emerging foreign market. The proposed DEA can be easily modified or extended to similar settings in other Asian countries such as India and East European countries. [ABSTRACT FROM AUTHOR]

The odor detection threshold for a chemical typically varies widely across population members, and the values can be described by a lognormal distribution. Assuming that the parameters of a chemical's odor detection threshold distribution can be estimated, a method is presented to retrospectively estimate exposure intensity based on detecting the chemical's odor. The context is a single exposure period involving a single air contaminant. In brief, where k out of n identically exposed persons detect the chemical's odor, the best estimate of the chemical's concentration in air corresponds to the k ÷ n fractile of the odor detection threshold distribution. Where n is small and/or k ÷ n is close to zero or one, exact 100 × (1 − α) % confidence bounds for the fractile estimate can be computed without using the normal distribution assumption. In addition, statistical uncertainty in the parameter estimates of the chemical's odor detection threshold distribution can be considered via a parametric bootstrap procedure, such that an overall 100 × (1 − α) % confidence interval on the chemical's concentration in air is obtained. The method is illustrated for benzene. Analysis of the available benzene odor detection threshold literature provides best estimates of a population geometric mean equal to 37.8 ppm and geometric standard deviation equal to 1.92. In a hypothetical example in which two out of six workers detect the odor of benzene, the point estimate of the benzene exposure level is 28.5 ppm, and the approximate one-sided lower 95% confidence limit is 8.2 ppm. The present analysis also makes clear that odor does not provide an adequate warning of excessive levels of airborne benzene. [ABSTRACT FROM AUTHOR]

This paper is concerned with formulating, exploring and interpreting the uses and constructs which may be derived from a mathematical model of programming type which expresses more realistically than past efforts the actual conditions of current operations. It is an attempt to provide a means of attaining thereby an objective understanding of the implications of actual Federal Reserve liquidity policy on the actions and opportunities of banking institutions. The model presented corresponds to the problem of determining an optimal portfolio for an individual bank over several time periods in accordance with requirements laid down by bank examiners which are interpreted as defining limits within which the level of risk associated with the return on the portfolio is an acceptable one. The problem is transformed into an equivalent one offering advantages of analysis and of computation. Some methods of effective computation are explored. [ABSTRACT FROM AUTHOR]

Many scholars suggest that visa restrictions push individuals who would have otherwise migrated legally toward illegal channels. This expectation is difficult to test empirically for three reasons. First, unauthorized migration is clandestine and often unobservable. Second, interpersonal ties between migrants and would-be migrants form a self-perpetuating system, which adapts in ways that are difficult to observe or predict. Third, empirical evaluations of immigration policy are vulnerable to endogeneity and other issues of causal inference. In this paper, we pair tailor-made empirical designs with an agent-based computational model (ABM) to capture the dynamics of a migration system that often elude empirical analysis, while grounding agent rules and characteristics with primary data collected in Jamaica, an origin country. We find that some government-imposed restrictions on migrants can deter total migration, but others are ineffective. Relative to a system of free movement, the minimal eligibility conditions required to classify migrants into visa categories alone make migration inaccessible for many. Restrictive policies imposed on student and high-skilled visa categories have little added effect because eligible individuals are likely able to migrate through alternative legal categories. Meanwhile, restrictions on family-based visas result in significant reductions in total migration. However, they also produce the largest reorientation toward unauthorized channels--an unintended consequence that even the highest rates of apprehension do not effectively eliminate. [ABSTRACT FROM AUTHOR]

Missing data is a common occurrence in epidemiologic research. In this paper, 3 data sets with induced missing values from the Collaborative Perinatal Project, a multisite US study conducted from 1959 to 1974, are provided as examples of prototypical epidemiologic studies with missing data. Our goal was to estimate the association of maternal smoking behavior with spontaneous abortion while adjusting for numerous confounders. At the same time, we did not necessarily wish to evaluate the joint distribution among potentially unobserved covariates, which is seldom the subject of substantive scientific interest. The inverse probability weighting (IPW) approach preserves the semiparametric structure of the underlying model of substantive interest and clearly separates the model of substantive interest from the model used to account for the missing data. However, IPW often will not result in valid inference if the missing-data pattern is nonmonotone, even if the data are missing at random. We describe a recently proposed approach to modeling nonmonotone missing-data mechanisms under missingness at random to use in constructing the weights in IPW complete-case estimation, and we illustrate the approach using 3 data sets described in a companion article (AmJ Epidemiol. 2018;187(3):568-575). [ABSTRACT FROM AUTHOR]

In 1906, James McKeen Cattell, editor of Science, published a directory of men of science. American Men of Science was a collection of biographical sketches of thousands of men of science in the USA and was published periodically. It launched, and was used in, the very first systematic quantitative studies on science. Cattell used two concepts for his statistics: productivity, defined as the number of men of science a nation produces, and performance or merit, defined as scientific contributions to research as judged by peers. These are the two dimensions that still define measurement of scientific productivity today: quantity and quality. This paper analyzes the emergence of statistics on science and the very first uses to which they were put. It argues that the measurement of science emerged out of interest in great men, heredity and eugenics, and the contribution of eminent men to civilization. Among these eminent men were men of science, the population of whom was thought to be in decline and insufficiently appreciated and supported. Statistics on men of science thus came to be collected to document the case, and to contribute to the advancement of science and the scientific profession. [ABSTRACT FROM AUTHOR]

Following a national trend of "getting tough" on increased juvenile crime, the Florida legislature eliminated one of the primary community service-oriented juvenile diversion programs, the Juvenile Alternative Services Program (JASP). JASP was subsequently replaced with four other diversion programs, two of which (the Walker Plan and an expanded Arbitration program) permitted greater penetration into the juvenile justice system. In a previous paper, we examined the impact of net-widening effects of diversion programs on youth participant recidivism for it six-month post-program period resulting from this shift in program funding. The results indicated that youths placed in the JASP program had significantly lower rates of new arrests and new arrest charges than each of the other four diversion programs. One of the consequences of the net-widening effects reported in this previous study could be an increase, rather than decrease, in the direct costs of a number of key justice services. The present study examines this issue by presenting the results of an economic impact analysis focusing on the direct costs incurred by various justice system agencies resulting from the youths' recidivism during the six-month post-program period. Stepwise multiple regression analyses predicting the cumulative cost (adjusted for inflation and overhead expenses) of providing justice services to the youths found that JASP had a lower direct cost rate with respect to the justice system than any of the JASP alternative programs. These findings, combined with those of our previous study, run contrary to one of the major concerns of policy makers: attaining better outcomes among at-risk youth while making the best use of scarce public resources. Theoretical and policy implications based on these results are discussed. [ABSTRACT FROM AUTHOR]

Oral-Dependent Language (ODL) is currently included in the Rorschach Performance Assessment System (R-PAS) as an empirically supported variable that measures both implicit and explicit psychological processes related to dependence and oral motives. To date, almost all studies on ODL have been conducted in the U.S. so that little is known about how it works in other cultural contexts. Additionally, no study has investigated the Oral and Dependent subcomponents of this variable. This paper addresses ODL validity in Italy and its clinical utility by reporting on three studies, each addressing a specific research question. Study 1 examined the association of gender, age, and cultural background to ODL scores. Study 2 addressed predictive validity by examining the relationship of ODL and its subcomponents' scores to dependent behaviors expressed by nonclinical participants in a laboratory task. Study 3 tested construct validity of ODL and its subcomponents scores via a clinical/nonclinical comparison paradigm. A total of 212 Italian participants (68 obese patients and nonobese volunteers) were enrolled in these studies. Data were analyzed through Bayesian and parametric techniques. Study 1 confirmed that Italian nonclinical individuals produced equivalent ODL scores to U.S. normative data; Study 2 found no association between ODL and occurrence of a dependency-related behavior in a laboratory setting; Study 3 showed that obese patients produced higher ODL scores than controls. [ABSTRACT FROM AUTHOR]

Models with multiple discrete breaks in parameters are usually estimated via least squares. This paper, first, derives the asymptotic expectation of the residual sum of squares and shows that the number of estimated break points and the number of regression parameters affect the expectation differently. Second, we propose a statistic for testing the joint hypothesis that the breaks occur at specified points in the sample. Our analytical results cover models estimated by the ordinary, nonlinear, and two-stage least squares. An application to U.S. monetary policy rejects the assumption that breaks are associated with changes in the chair of the Fed. [ABSTRACT FROM AUTHOR]

Abstract--In many practical applications, one is interested in obtaining confidence intervals for nonlinear functions of the parameters. This paper considers the following different methods: Fieller's method, Taylor's series expansion, and bootstrap methods. Compared to some of the earlier results in the empirical studies that are against the application of bootstrap, our results suggest a different conclusion in favor of the bootstrap methods. [ABSTRACT FROM AUTHOR]

The conditions under which interdisciplinary research helps improve research performance are explored in a heterogeneous sample of 67 ongoing academic interdisciplinary teams from the United States and Canada. We conclude that interdisciplinary research is more appropriate for very difficult research questions and at early stages of the research process. Interdisciplinary research was found to inhibit the outputs of articles, books, papers, and technical reports when the research had a clearly identified client prior to the start of the project. Interdisciplinary research was not found to be more helpful for either applied or pure research. It was not found to be helpful either at the concluding stage of research or when used throughout the research process. [ABSTRACT FROM AUTHOR]

This paper explores changes in the number of utopian novels published in Great Britain and the United States between 1883 and 1975 from a world-system perspective. A time-series analysis indicates that the publication of utopian literature was affected by changes in the world economy and by changes in the organization of the core of the world-system. On the basis of these findings, we argue that the world-system perspective represents a promising approach for the study of cross-national cultural change. [ABSTRACT FROM AUTHOR]

The research reported herein was performed pursuant to a contract with the United States Department of Health, Education, and Welfare, Office of Education, Contract OE 5-10-292. The author is grateful to Professors Hubert M. Blalock, Jr., David Elesh, and David Heise for comments on an earlier version of this paper. However, the author takes full responsibility for errors that remain. [ABSTRACT FROM AUTHOR]

In this paper we investigate the relationship between leverage and the level of economic activity in the United States, using quarterly data over the period 1951–2012. We address the question for five different measures of leverage—household leverage, nonfinancial firm leverage, commercial bank leverage, broker–dealer leverage, and shadow bank leverage—making a distinction between traditional banks and shadow banks, the latter being a consequence of financial innovation and deregulation in the financial services industry over the past 30 years. We investigate whether the relationship between leverage and the level of economic activity is nonlinear and asymmetric using slope-based tests as well as tests of the null hypothesis of symmetric impulse responses. Our results inform policymakers about the important distinction between traditional banks and the market-based financial intermediaries that have been at the center of the global financial crisis of 2007–2009. They also inform about the macroeconomic effects of the deleveraging process that began in 2008, as well as about the need for countercyclical macroprudential policies to reduce the procyclicality of the financial system. [ABSTRACT FROM AUTHOR]

The spatial scan statistic is one of the main epidemiological tools to test for the presence of disease clusters in a geographical region. While the statistical significance of the most likely cluster is correctly assessed using the model assumptions, secondary clusters tend to have conservatively high P-values. In this paper, we propose a sequential version of the spatial scan statistic to adjust for the presence of other clusters in the study region. The procedure removes the effect due to the more likely clusters on less significant clusters by sequential deletion of the previously detected clusters. Using the Northeastern United States geography and population in a simulation study, we calculated the type I error probability and the power of this sequential test under different alternative models concerning the locations and sizes of the true clusters. The results show that the type I error probability of our method is close to the nominal a level and that for secondary clusters its power is higher than the standard unadjusted scan statistic. [ABSTRACT FROM AUTHOR]

Using data from the National Health Interview Survey for years spanning 1976 and 2001, this paper presents an age–period–cohort analysis of weight gain throughout the life cycle. We find that while all ages experienced an increase in the prevalence of those overweight and/or obese, the prevalence among young adults has grown at a faster rate than that of older age groups. The increases in body mass index are primarily due to period effects, not cohort or age effects. From the ordered logistical regression analyses, we find that the protective influence of factors such as education, income, and age on an individual’s body mass index have decreased over time. The analyses suggest that the increase in the prevalence of those overweight or obese is a phenomenon experienced by all demographic groups in the US, albeit to differing degrees. [ABSTRACT FROM AUTHOR]

This paper shows how record-value theory, a branch of statistics that deals with the timing and magnitude of extreme values in sequences of random variables, can be used to recover features of the wage offer distribution in conventional search models. Using National Longitudinal Survey of Youth (NLSY) wage data, I show that the data are not compatible with specifications for the offer distribution characterized by extreme negative skewness. In addition, I show that my approach can be used to construct a bound on the returns to job seniority. My results suggest that job seniority plays only a minor role in the wage growth of the workers surveyed in the NLSY. [ABSTRACT FROM AUTHOR]

Monthly rainfall estimates inferred from the NASA Tropical Rainfall Measuring Mission (TRMM) satellite contain errors due to discrete temporal sampling and remote spaceborne rain retrievals. This paper develops a regional-scale error model that uses the rain information in the ground data to disentangle the sampling and retrieval errors in the satellite estimate statistically. The proposed method computes a mean rain rate from monthly rainfall statistics for each TRMM rain sensor by subsampling high-resolution ground-based rain data at satellite overpass times. This additional rain-subsampled parameter plays an essential role in the statistical decomposition of the total error distribution into its sampling and retrieval error components. Using the statistical formalism developed in this study, an error analysis was performed on 5 yr of monthly rain estimates produced by the TRMM Microwave Imager (TMI) and precipitation radar (PR) rain sensors aboard TRMM over a quasi 2° × 2° region of the TRMM ground validation (GV) site at Melbourne, Florida. Annual retrieval and sampling error statistics were computed for the TMI and PR using monthly rainfall estimates derived from two independent ground-based sensors: a regional rain gauge network and the Next-Generation Weather Radar (NEXRAD). Subsampled ground-based rainfall estimates produced for the radar and the gauges were highly correlated with the TMI and PR rainfall estimates, and both GV sensors produced relatively consistent error estimates. The PR-to-TMI sampling error ratio was equal to about 1.3, which was in close agreement with prelaunch predications, and the TMI-to-PR retrieval error ratio was about 2.0. For the TMI, a seasonally alternating rainfall bias was also observed that was negative during winter and positive during summer. [ABSTRACT FROM AUTHOR]

A commercially available differential fuel-cell analyzer has been adapted to make field-based ppm-level measurements of atmospheric O2 variations. With the implementation of rapid calibrations and active pressure and flow control, the analysis system described here has a 1σ precision of ±2.5 per meg (≈0.5 ppm) for a 2-min measurement. Allowing for system stabilization after switching inlet lines, a 6-min measurement with a precision of ±1.4 per meg (≈0.3 ppm) every 20 min is obtained. The elimination of biases in any atmospheric O2 measurement depends critically on careful gas-handling procedures, and after screening for known sources of bias a comparability of ±10 per meg (≈2 ppm) with the present setup is estimated. In comparison to existing techniques, the relatively small size, low cost, fast response, motion insensitivity, and ease of implementation of the fuel-cell analyzer make it particularly useful for a wide range of unattended field applications. This system has been used to measure atmospheric O2 concentrations at the WLEF tall-tower research site in northern Wisconsin semicontinuously from June 2000 to December 2003. These measurements represent the first extended O2 record in and above a forest ecosystem, and are being used to investigate global carbon budgeting, plant physiology, continental boundary layer mixing and synoptic transport, and potential means of industrial emission verification. In this paper, the measurement technique is described in detail and several weeks of data are presented to illustrate its performance. [ABSTRACT FROM AUTHOR]

Nonlinear time series models have become fashionable tools to describe and forecast a variety of economic time series. A closer look at reported empirical studies, however, reveals that these models apparently fit well in-sample, but rarely show a substantial improvement in out-of-sample forecasts, at least over linear models. One of the many possible reasons for this finding is the use of inappropriate model selection criteria and forecast evaluation criteria. In this paper we therefore propose a novel criterion, which we believe does more justice to the very nature of nonlinear models. Simulations show that this criterion outperforms those criteria currently in use, in the sense that the true nonlinear model is more often found to perform better in out-of-sample forecasting than a benchmark linear model. An empirical illustration for US GDP emphasizes its relevance. [ABSTRACT FROM AUTHOR]

This paper examines some of the economic and econometric issues that arise in attempting to measure the degree of concentration in an industry and its dynamic evolution. A general axiomatic basis is developed. We offer new measures of concentration over aggregated periods of time and provide a sound statistical basis for inferences. Concentration is one aspect of the problem of measuring “market power” within an industry. Modern economic analysis of antitrust issues does not focus only on the level of concentration, but still must examine the issue carefully. We contrast concentration at a point in time with a dynamic profile of change in the distribution of shares in a given market. Our methods are demonstrated with an application to the US steel industry. [ABSTRACT FROM AUTHOR]

Since the early work of RA Fisher, exact methods have been recognized as important tools in data analysis because they provide valid statistical inference even with small sample sizes, or with sparse or skewed data. With the recent advance of computational power and the availability of commercial software packages, exact methods have gained substantial popularity over the past two decades. However, most of these exact methods have been devoted to testing classical null hypotheses of no differences, and until recently little was known about exact methods dealing with non-inferiority or equivalence hypotheses. The presence of nuisance parameters in testing non-inferiority/equivalence hypotheses presents a special challenge for exact methods because of the intense computational requirement. In this paper, we review exact methods available for proving non-inferiority or equivalence of two treatments with a dichotomous endpoint. First, we present the general methodology for conducting exact tests for non-inferiority or equivalence; we then discuss several unconditional and conditional methods available for constructing hypothesis tests and confidence intervals based on three commonly used measures, namely, the difference, relative risk, and odds ratio of two independent proportions or rates. Finally, we illustrate with several examples the application of these exact methods in analysing and planning non-inferiority or equivalence trials. [ABSTRACT FROM AUTHOR]

This paper proposes a measure of dynamic comovement between (possibly many) time series and names it cohesion. The measure is defined in the frequency domain and is appropriate for processes that are costationary, possibly after suitable transformations. In the bivariate case, the measure reduces to dynamic correlation and is related, but not equal, to the well known quantities of coherence and coherency. Dynamic correlation on a frequency band equals (static) correlation of bandpass-filtered series. Moreover, long-run correlation and cohesion relate in a simple way to co-integration. Cohesion is useful to study problems of business-cycle synchronization, to investigate short-run and long-run dynamic properties of multiple time series, and to identify dynamic clusters. We use state income data for the United States and GDP data for European nations to provide an empirical illustration that is focused on the geographical aspects of business-cycle fluctuations. [ABSTRACT FROM AUTHOR]

Provides distribution-free inferences for testing marginal rank dominance and Lorenz, and generalized Lorenz dominances. Relationships holding between an income distribution and its dependent after-event distribution; Asymptomatic normal distributions of sample marginal changes; Re-evaluation of marginal impacts of working wives of the United States family income distribution.

Rural areas and the rural South in particular have unique characteristics that render inappropriate many urban-oriented housing affordability approaches, delivery systems and programs. In addition, a lack of data for smaller communities makes accurate assessments of the housing stock difficult This paper explores factors that influence housing affordability. A methodology is developed that policy makers in local communities can use with volunteers to collect reliable data and to develop a local housing agenda which meets community needs. Regression analysis using data from four rural Georgia communities reveals that housing quality plays a role in housing expenditures. The paper concludes with strategies for rural community housing assessment and implementation. [ABSTRACT FROM AUTHOR]

This paper examines the issues associated with enhancing the sample design of the next cycle of the National Medical Expenditure Survey (NMES) Household Component, in order to allow for state level estimates of health care parameters. The NMES household survey was designed to produce estimates of the civilian non-institutionalized population for calendar year 1987. While small area estimation techniques can be used to produce model-based estimates with the current NMES-2 design, there are serious concern with respect to their accuracy and reliability. This evaluation reviews the coverage and precision requirements of other national surveys that produce state level estimates. Alternative options to enhance the capacity for producing state level estimates in NMES-3 are also examined. [ABSTRACT FROM AUTHOR]

A proper analysis of data from complex sample surveys requires special consideration for estimating standard errors. Special techniques and software packages are available, including Taylor series linearization (delta method), balanced repeated replication, and jackknife. Before their use, it is often necessary to make certain modifications in original data structure, to conform to computing method requirements. The most common modification is to form pseudostrata by collapsing substrata or partitioning a string of geographic clusters. This paper examines the performance of the delta method when it is applied to a complex community survey data set in which sequentially drawn clusters of households are partitioned to form pseudostrata. Standard errors of rates, regression coefficients, and odds ratios are compared with those computed from the variation of replicates built into the sample design. The results demonstrate that an analysis of complex survey data should use an appropriate method for estimating standard errors, and that pseudostrata would produce reasonable estimates of standard errors for rates and regression coefficients, with mixed results for odds ratios. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes the variation in use of soup kitchens throughout the month using data from the New York State Nutritional Surveillance Program. Excluding November, December, and May, when holiday meals created a different pattern of use, number of meals served in soup kitchens generally increased toward the end of the month, averaging 43 per ¢ higher for Upstate and 14 per ¢ higher for New York City in the last week as compared to the first week of the month. The overall increase throughout the month and difference in the magnitude of increase between Upstate and New York City corresponds to the timing of income maintenance benefits distribution. Distribution of most public assistance benefits occurs at the beginning of each month in Upstate, whereas it is staggered in New York City throughout the month. (Am J Public Health 1988; 78:1298-1301.) [ABSTRACT FROM AUTHOR]

The article presents information about Samuel S. Wilks, a great contributor to statistics. Wilks' behavior toward applications was peculiarly split, he encouraged his students to work on applications, not always an easy thing to do in a strongly theoretical mathematics department; he often told students about applications that he regarded as "neat" or "cute" or "clever"; the statistical colloquium he guided often had speakers on practical applications of mathematical statistics; he himself wrote some practical papers in statistics, but in the classroom he rarely discussed applications. Repeatedly, however, practical problems explicitly influenced both his own publications and those of his students and Wilks often used applications as motivation for the discussion of distribution theory, usually going well beyond the needs of the original problem. The papers to be discussed exhibit incompletely and fragmentarily a major influence on the work of the man and his students. Wilks watched the development of the statistical theory of order statistics closely. Indeed he wrote a masterful summary of the literature. The general area involves the study of the statistical properties of ordered measurements.

In a previous paper [12], an attempt was made to show how spectral techniques could be used to compare the effects of two seasonal adjustment procedures on the series to which they were applied. The two procedures compared were: (a) the technique currently used by the Bureau of Labor Statistics for seasonally adjusting employment, unemployment, and labor force monthly statistics, and (b) the so-called "residual" method, proposed by Brittain [2], Samuelson [16], and others. Spectra of the original and the seasonally adjusted series and the cross spectrum of the two were used to aid in the assessment of whether either procedure removed more than could be considered seasonal, introduced spurious regularities, and/or distorted temporal relationships. It was concluded that both techniques removed more than seasonal effects from, and produced some temporal distortion in, the series to which they were applied. Neither method appeared to be superior to the other. It is the purpose of this paper to carry the previous analysis one step further and to compare the BLS procedure with a modified version of the regression method of seasonal adjustment suggested by Cowden [3] and Mendershausen [11], and recently revived by Harman [9, 10] in an exceptionally sophisticated form. In addition to Hannan's work along the lines suggested, Nettheim [13] and Rosenblatt [15] have made studies. Rosenblatt [15] has carried out analyses similar to those reported here. [ABSTRACT FROM AUTHOR]

This is a report from project No.5-0074 (EO-191), "Socioeconomic Background and Occupational Achievement: Extensions of a basic Model." Supported by Contract No.OE-5-85-072 with the U.S. Office of Education. It was prepared with the assistance of David L. Featherman, J. Michael Coble, and Elliot Long. In kindly making available the data use din the report, professor Charles F. West ff of Princeton university assumes, of course, no responsibility for the interpretations of those data offered here. A preliminary version of this paper, entitled "Motives and Mobility," was presented at the 1967 annual meeting of the American Sociological Association. [ABSTRACT FROM AUTHOR]

This study has two purposes. One is to examine the substantive question: is there statistical evidence that money is "exogenous" in some sense in the money-income relationship? The other is to display in a simple example some time-series methodology not now in wide use. The main methodological novelty is the use of a direct test for the existence of unidirectional causality. This test is of wide importance, since most efficient estimation techniques for distributed lags are invalid unless causality is unidirectional in the sense of this paper. Also, the paper illustrates the estimation of long lag distributions without the imposition of the usual restrictions requiring the shape of the distribution to be rational or polynomial. The main empirical finding is that the hypothesis that causality is unidirectional from money to income agrees with the postwar U.S. data, whereas the hypothesis that causality is unidirectional from income to money is rejected. It follows that the practice of making causal interpretations of distributed lag regressions of income on money is not invalidated by the existence of "feedback" from income to money.

The "spiritual but not religious" (SBNR) are a growing group in the religious landscape of the United States. Thousands of studies to date have been devoted to the study of religion and health, but far less attention has been given to the study of the "spiritual but not religious." In this study, we address this gap by using two waves of longitudinal data from the National Study of Youth and Religion (2005–2008). We assess whether within-person changes in SBNR identity are associated with health and mental health in emerging adulthood and consider several pathways that may account for observed differences. Results suggest that consistently identifying as SBNR was associated with worse physical and mental health relative to youth that were consistently religious. Using parametric mediation analyses, we found evidence that three of our four proposed mediators (religious attendance, sense of closeness to God, and religious doubt, but not life meaning) partially explained these mental health differences. This study therefore makes an important advance in assessing the health implications of (non)-religion/spirituality early in the life course. [ABSTRACT FROM AUTHOR]

The article presents a response to the criticism of Paula Voos concerning the authors' paper about the determinants of unionism in the U.S. Voos criticizes the paper for two reasons: the absence of notation of significance levels where the signs of variable coefficients were presented; and the pooling of cross-sectional studies employing different measures of unionization. The authors points that Voos may be correct in stating that time-series research would not profit from adopting education as an explanatory variable.

In this article the author comments on the research of Professor Bradley Efron that investigates the efficacy of correlation in multiple testing in the U.S. He believes that in large-scale multiple testing problems, the distribution of test statistics does not often match the theoretical null distribution. He believes that Efron is right in his assumption that test statistics are different from theoretical null distribution.

In the aftermath of the 2007-2008 financial crisis, there has been criticism of mathematics and the mathematical models used by the finance industry. We answer these criticisms through a discussion of some of the actuarial models used in the pricing of credit derivatives. As an example, we focus in particular on the Gaussian copula model and its drawbacks. To put this discussion into its proper context, we give a synopsis of the financial crisis and a brief introduction to some of the common credit derivatives and highlight the difficulties in valuing some of them. We also take a closer look at the risk management issues in part of the insurance industry that came to light during the financial crisis. As a backdrop to this, we recount the events that took place at American International Group during the financial crisis. Finally, through our paper we hope to bring to the attention of a broad actuarial readership some "lessons (to be) learned" or "events not to be forgotten". [ABSTRACT FROM AUTHOR]

Born in New Zealand, Shayle Robert Searle earned a bachelor's degree (1949) and a master's degree (1950) from Victoria University, Wellington, New Zealand. After working for an actuary, Searle went to Cambridge University where he earned a Diploma in mathematical statistics in 1953. Searle won a Fulbright travel award to Cornell University, where he earned a doctorate in animal breeding, with a strong minor in statistics in 1959, studying under Professor Charles Henderson. In 1962, Cornell invited Searle to work in the university's computing center, and he soon joined the faculty as an assistant professor of biological statistics. He was promoted to associate professor in 1965, and became a professor of biological statistics in 1970. Searle has also been a visiting professor at Texas A&M University, Florida State University, Universität Augsburg and the University of Auckland. He has published several statistics textbooks and has authored more than 165 papers. Searle is a Fellow of the American Statistical Association, the Royal Statistical Society, and he is an elected member of the International Statistical Institute. He also has received the prestigious Alexander yon Humboldt U.S. Senior Scientist Award, is an Honorary Fellow of the Royal Society of New Zealand and was recently awarded the D.Sc. Honoris Causa by his alma mater, Victoria University of Wellington, New Zealand. [ABSTRACT FROM AUTHOR]

Purpose - The purpose of this paper is to examine a US retailer's decision to backward-integrate its supply channel for global sourcing, based on the framework adapted from transaction cost analysis (TCA). Design/methodology/approach - The conceptual framework was developed based on the past literature. A survey method was employed to collect the data from apparel retail firms engaging in global sourcing. Confirmatory factor analysis and ordinal regression analysis were used to diagnose the quality of data and to test hypotheses. Findings - A retail firm avoids backward integration when facing high volume fluctuation and high country risk combined with asset specificity, while it favors the integration when perceiving high asset specificity, socio-cultural distance, free-ride potential, and sourcing volume. Great experience also leads to backward integration not only as a main factor, but also as a moderator reinforcing the effects of asset specificity and uncertainty on integration. Originality/value - Although transaction costs associated with foreign procurement are highly significant, little attempt has been made so far to apply TCA to understand sourcing governance decisions, in particular those by retailers - important participants in the current landscape of global sourcing. This study fills this gap. This study also examines the role of import volume, experience, and free ride potential to provide a more comprehensive understanding of sourcing governance decisions by retailers. [ABSTRACT FROM AUTHOR]

There is a strong cross-sectional association between military service and adverse health. However, veterans differ very significantly in their observable characteristics from nonveterans, suggesting that some of the association between military service and adverse health may be due to omitted variables bias. To address this problem, we use draft eligibility as an instrument for military service. Despite a very strong first-stage relationship between draft eligibility and military service, the two-stage least squares estimates of the difference in health between veterans and nonveterans are statistically insignificant and too imprecise to preclude the differences in health found in the cross-sectional regressions. ( JEL H56, I12, I18) [ABSTRACT FROM AUTHOR]

In this article, we report statistical properties of two classes of generalized Gini coefficients (G1 and G2). The theoretical results were assessed via Monte Carlo simulations. Further, we used G1 and G2 on life expectancy to measure health inequalities among the provinces of China and the states of the United States. For China, the results indicated that there was statistically significant health inequality by both G1 and G2. However, for the US, the results showed that there was significant health inequality by G1 but no statistical significance was found in health inequality by G2. Overall, from our study, China has higher health inequality than the United States. [ABSTRACT FROM AUTHOR]

A multivariate regime-switching model for monetary policy is confronted with U.S. data. The best fit allows time variation in disturbance variances only. With coefficients allowed to change, the best fit is with change only in the monetary policy rule and there are three estimated regimes corresponding roughly to periods when most observers believe that monetary policy actually differed. But the differences among regimes are not large enough to account for the rise, then decline, in inflation of the 1970s and 1980s. Our estimates imply monetary targeting was central in the early 1980s, but also important sporadically in the 1970s. [ABSTRACT FROM AUTHOR]

This article examines monthly U.S. inflation rates by means of fractionally integrated time series techniques. We use a procedure of Robinson (J Am Statist Assoc 1994; 89:1420) that permits us to simultaneously test the degrees of integration at both the zero and the seasonal frequencies. The results show that long memory takes place at both frequencies, the orders of integration being in both cases higher than 0 but smaller than 0.5, implying stationarity but long memory behaviour. In addition, the root at the long run or zero frequency seems to play a much more important role than the seasonal one, with shocks affecting the latter component decaying faster than in the former case. Copyright © 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objective: To investigate the impact of smoking on the wealth of US young baby boomers. Methodology: The research analyses self reported responses of both smoking habits and wealth holdings from a nationally representative sample of US individuals born between 1957 to 1964 (n = 8908). Data are from four waves (1984, 1992, 1994, 1998) of the National Longitudinal Survey of Youth 1979 cohort, a random survey of individuals conducted by the US Department of Labor using a stratified multistage area sample design. Results: Regression results show lower net worth is associated with smoking, after holding constant a variety of demographic factors. Respondents who were ever heavy smokers are associated with a reduction in net worth of over $8300 while light smokers are $2000 poorer compared to non-smokers. Beyond this reduction, each adult year of smoking is associated with a decrease in net worth of $410 or almost 4%. Conclusions: While a causal relation cannot be proven, smokers appear to pay for tobacco expenditures out of income that is saved by non-smokers. Hence, reductions in smoking will boost wealth, especially among the poor. [ABSTRACT FROM AUTHOR]

Reports on the relationship between group size and eta-squared in analysis of variance from researchers at the Walter Reed Army Institute of Research. Conditions under which eta-squared does and does not provide a biased estimate of group level properties; Correction for eta-squared; Guidelines for calculating estimates of group-level properties in samples having unequal group sizes.

This paper addresses the question: "What is an appropriate statistical procedure for testing the electronic reliability of nuclear powered cardiac pacemakers?" A sequential test procedure is described, assuming a constant failure rate, together with a method for testing the validity of this assumption. The methods described herein were recommended by the authors to the U.S. Atomic Energy Commission, Directorate of Licensing, and subsequently appeared as The Generic Environmental Statement on Routine Use of Plutonium Powered Cardiac Pacemakers, July, I976, Document NUREG 0060, issued by the Nuclear Regulatory Commission. [ABSTRACT FROM AUTHOR]