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Ronald Fisher was probably the greatest statistician of the twentieth century. Gertrude Cox was an expert on experimental designs and an outstanding administrator and developer of statistical departments, first in North Carolina and then worldwide. These two associated in various roles for thirty years, on U.S. campuses and at international statistical associations. They were both founding members of the international Biometric Society in 1947. A major collision came in 1953, when Cox was editor of Biometrics. Fisher submitted an article critical of four contemporary statisticians and did not want to change it. Cox published his article and comments by the four, all in the same issue. There was deep underlying respect, however, and Fisher lectured and taught for Cox in North Carolina afterward. They continued to correspond, and to meet occasionally, until Fisher’s death in 1962. [ABSTRACT FROM AUTHOR]

In order to manage model risk, financial institutions need to set up validation processes so as to monitor the quality of the models on an ongoing basis. Validation can be considered from both a quantitative and qualitative point of view. Backtesting and benchmarking are key quantitative validation tools, and the focus of this paper. In backtesting, the predicted risk measurements (PD, LGD, EAD) will be contrasted with observed measurements using a workbench of available test statistics to evaluate the calibration, discrimination and stability of the model. A timely detection of reduced performance is crucial since it directly impacts profitability and risk management strategies. The aim of benchmarking is to compare internal risk measurements with external risk measurements so as to better gauge the quality of the internal rating system. This paper will focus on the quantitative PD validation process within a Basel II context. We will set forth a traffic light indicator approach that employs all relevant statistical tests to quantitatively validate the used PD model, and document this approach with a real-life case study. The set forth methodology and tests are the summary of the authors' statistical expertise and experience of world-wide observed business practices. [ABSTRACT FROM AUTHOR]

The article presents information on the content and operation related to the periodical "The American Statistician," (TAS) for 2004. The Software Reviews Section presented seven reviews during the calendar year 2004. Each issue was accompanied with a Section Editor's Notes by Joseph Hilbe, which summarized the reviews in each issue, discussed other software, and relayed other related information of interest to the statistical community.

The article presents information on the content and operation related to the periodical "The American Statistician," (TAS) for 2004. In 2004, 237 books were received for review, and 46 of those were identified as teaching-related and hence designated for review in TAS. Full-length book reviews published in 2004 total 20. There were also two "brief reviews" articles in which 14 more books are reviewed, for a total of 34 books. This compares with 31 books reviewed in 2003, and 29 in 2002. Full reviews in 2004 include books on baseball, bio-statistics, common statistical errors, courseware, grade inflation, introductory statistics, practice problems, probability theory, proofs, R, regression and ANOVA, SAS, S-Plus, and stochastic modeling.

This article examines the role of statistics in the age of information technology (IT). It begins by examining the current state of IT and of the cyberinfrastructure initiative aimed at integrating the technologies into science, engineering, and education to convert massive amounts of data into useful information. Selected applications from science and text processing are introduced to provide concrete examples of massive data sets and the statistical challenges that they pose. The thriving field of machine learning is reviewed as an example of current achievements driven by computations and IT. Ongoing challenges that we face in the IT revolution are also highlighted. The paper concludes that for the healthy future of our field, computer technologies have to be integrated into statistics, and statistical thinking in turn must be integrated into computer technologies. [ABSTRACT FROM AUTHOR]

College instructors often provide students with only summative evaluations of their work, typically in the form of exam scores or paper grades. Formative evaluation, such as classroom assessment techniques (CATs), are more rare in higher education and provide an ongoing evaluation of students' progress. In this article, the author summarizes the use of CATs in an undergraduate introductory statistics course and present data indicating that students believed CATs increased their understanding of material and benefited their academic performance. With minor revision, these CATs can be effectively used in other disciplines. [ABSTRACT FROM AUTHOR]

This paper discusses the reliance of numerical analysis on the concept of the standard deviation, and its close relative the variance. It suggests that the original reasons why the standard deviation concept has permeated traditional statistics are no longer clearly valid, if they ever were. The absolute mean deviation, it is argued here, has many advantages over the standard deviation. It is more efficient as an estimate of a population parameter in the real-life situation where the data contain tiny errors, or do not form a completely perfect normal distribution. It is easier to use, and more tolerant of extreme values, in the majority of real-life situations where population parameters are not required. It is easier for new researchers to learn about and understand, and also closely linked to a number of arithmetic techniques already used in the sociology of education and elsewhere. We could continue to use the standard deviation instead, as we do presently, because so much of the rest of traditional statistics is based upon it (effect sizes, and the F-test, for example). However, we should weigh the convenience of this solution for some against the possibility of creating a much simpler and more widespread form of numeric analysis for many. [ABSTRACT FROM AUTHOR]

Hospital length of stay is considered to be a reliable and valid proxy for measuring the consumption of hospital resources. Average length of stay, however, albeit easy to quantify and calculate, does not suitably reflect the nature of such underlying distributions and may therefore mask the effects that the different streams of patients have on the system. This paper uses routinely collected and readily available nationwide data on stroke-related patients, aged 65 years and over, who were discharged from English hospitals over a 1-year period. This will be the basis for a running example illustrating the alternative methods of analysis and models of patients' length of stay. The methods include statistical methods: survival analysis, mixed exponential and phase-type distributions; and decision modelling techniques: compartmental and simulation models. The paper concludes by summarizing these various modelling techniques and by highlighting the similarity of the estimated parameters of patient flow as calculated by the phase-type distribution and compartmental modelling techniques. [ABSTRACT FROM AUTHOR]

This paper reports on an application a multivariate analysis technique called Co-Plot. It replicates a study conducted among leading MBA programmes in the United States using the same technique; a statistical method especially suited for this type of analysis where there are samples with relatively few observations (business schools) and large numbers of variables (subject modules, core and elective). Using Co-Plot the paper presents a mapping of the structure of 32 Association of Masters of Business Administration (AMBA) accredited MBA programmes in the United Kingdom and compares the characteristics of the resultant groupings of MBA programmes and the relationship between group membership. The patterns of core and elective modules offered by the selected MBA programmes are then compared with the rankings of UK business schools. The research shows that in the UK, unlike in the US, the clustering is not as strong and clear. Five groups/clusters of schools are identified together with four main clusters of core and electives modules offered. Differentiation is only significant when the electives modules are taken into account unlike the US where differentiation is evident between programmes with the core modules. [ABSTRACT FROM AUTHOR]

This paper draws on a study of numeracy coordinators in primary schools in the UK in the second year of the implementation of the National Numeracy Strategy (NNS). It identifies them as working between three main tasks: embedding the Strategy, sustaining teacher collegiality and auditing accountability. We identify tensions in ‘being a coordinator’ in relation to these tasks, especially for discourse and identity. We assess the usefulness of the metaphor of ‘brokering’ in ‘commun-ities of practice’ (Wenger, 1998) to theorise such tensions. We conclude with some reservations about the metaphor, especially in the way the tensions are discursively performed in relation to the rate of change, complexity of notions of professional identity, and the problematic ‘community’ status of audit in the educational context. [ABSTRACT FROM AUTHOR]

This article comments on the paper by Sergio Pastorello, Valentin Patilea and Eric Renault which offers an important analysis of possible estimation strategies for general class of dynamic models and shows that many of them can be viewed as backfitting. The major advantage of this estimation strategy is simplified optimization, which comes at a cost of some statistical efficiency loss. The authors motivate their paper by the fundamental theorem of asset pricing. The discussion by the authors gives a sense of the role of latent state variables in the asset pricing models. It is worthwhile to note that in many realistic asset pricing applications, the closed-form likelihood or moment conditions do not exist. Moreover, the backfitting procedure is questionable in a case discussed because of the absence of nuisance parameters and disconnection between statistical parameters θ and risk premium parameters λ[subp]. The backfitting procedure effectively allows one to operate on the likelihood of the state variables rather than observables. The most natural application of this estimation strategy in asset pricing is when one can observe some of the prices exactly, that is, able to invert them to obtain state variables, but other prices are observed with an error. The most prominent example of this is term structure modeling

This article presents the Markov chain Monte Carlo (MCMC) statistical technique. The impact on the discipline is deep and durable, because these methods have opened new horizons in the scale of the problems that one can deal with, thus enhancing the position of statistics in most applied fields. The MCMC revolution has in particular boosted Bayesian statistics to new heights by providing a virtually universal tool for dealing with integration problems. This can be seen in the explosion of papers dealing with complex models, hierarchical modelings, nonparametric Bayesian estimation, and spatial statistics. This trend has also created new synergies with mathematicians and probabilists, as well as econometricians, engineers, ecologists, astronomers, and others, for theoretical requests and practical implications of MCMC techniques. The main factor in the success of MCMC algorithms is that they can be implemented with little effort in a large variety of settings. This is obviously true of the Gibbs sampler, which provided some conditional distributions are available as shown by the BUGS software. We mentioned BUGS and CODA as existing software dedicated to MCMC algorithms but much remains to be done before MCMC becomes part of commercial software.

This article discusses the state of statistical process control as we proceed into the 21st century. SPC refers to some statistical methods used extensively to monitor and improve the quality and productivity of manufacturing processes and service operations. SPC primarily involves the implementation of control charts, which are used to detect any change in a process that may affect the quality of the output. The first control charts were developed by Walter A. Shewhart in the 1920s. These simple Shewhart charts have dominated applications to date. The process-monitoring problem can be described in general terms. Murphy's law explains the purpose monitoring: over time, something will inevitably change and possibly cause deterioration in process quality. The Shewhart charts were designed to make it relatively easy for process personnel without statistical training to set up, apply, and interpret the charts using only a pencil and paper for calculations. Bayesian procedures appear to be naturally suited for process monitoring. The standard approach to sampling for a control chart is to use a fixed sampling rate in which samples of fixed size are obtained using a fixed-length sampling interval.

The article presents information on a study which described capture-recapture models for the estimation of demographic parameters of wild animal populations. The capture-recapture models are now also widely used in a variety of other applications such as the census undercount, incidence of disease, criminality, homelessness and computer bugs. Although they have their historical roots in the twentieth century, capture-recapture models are basically a twentieth century phenomenon. Often capture-recapture studies have a long duration, rendering the closed models impractical. Thus there has been a need for the development of models that allow for additions and deletions. Another focus of research has been to develop combinations of different sampling methods. One early example used a robust design that combines both open and closed models in one analysis. Since then many papers have used this design for many reasons, for example, to allow for unequal catchability, to separate recruitment from immigration and to estimate temporary emigration.

Consider a finite sample from an unknown distribution over a countable alphabet. The missing mass refers to the probability of symbols that do not appear in the sample. Estimating the missing mass is a basic problem in statistics and related fields, which dates back to the early work of Laplace, and the more recent seminal contribution of Good and Turing. In this article, we introduce a generalized Good-Turing (GT) framework for missing mass estimation. We derive an upper-bound for the risk (in terms of mean squared error) and minimize it over the parameters of our framework. Our analysis distinguishes between two setups, depending on the (unknown) alphabet size. When the alphabet size is bounded from above, our risk-bound demonstrates a significant improvement compared to currently known results (which are typically oblivious to the alphabet size). Based on this bound, we introduce a numerically obtained estimator that improves upon GT. When the alphabet size holds no restrictions, we apply our suggested risk-bound and introduce a closed-form estimator that again improves GT performance guarantees. Our suggested framework is easy to apply and does not require additional modeling assumptions. This makes it a favorable choice for practical applications. for this article are available online. [ABSTRACT FROM AUTHOR]

Scientific journals may counter the misuse, misreporting, and misinterpretation of statistics by providing guidance to authors. We described the nature and prevalence of statistical guidance at 15 journals (top-ranked by Impact Factor) in each of 22 scientific disciplines across five high-level domains (N = 330 journals). The frequency of statistical guidance varied across domains (Health & Life Sciences: 122/165 journals, 74%; Multidisciplinary: 9/15 journals, 60%; Social Sciences: 8/30 journals, 27%; Physical Sciences: 21/90 journals, 23%; Formal Sciences: 0/30 journals, 0%). In one discipline (Clinical Medicine), statistical guidance was provided by all examined journals and in two disciplines (Mathematics and Computer Science) no examined journals provided statistical guidance. Of the 160 journals providing statistical guidance, 93 had a dedicated statistics section in their author instructions. The most frequently mentioned topics were confidence intervals (90 journals) and p-values (88 journals). For six "hotly debated" topics (statistical significance, p-values, Bayesian statistics, effect sizes, confidence intervals, and sample size planning/justification) journals typically offered implicit or explicit endorsement and rarely provided opposition. The heterogeneity of statistical guidance provided by top-ranked journals within and between disciplines highlights a need for further research and debate about the role journals can play in improving statistical practice. [ABSTRACT FROM AUTHOR]

Computer program analysis refers to the automatic analysis of the behavior of a user defined program. An application of program analysis is to determine the quality of source code. Humans are prone to errors and, in most cases, the penalty of deploying low quality code is very high for a large organization. These errors often give rise to potential security vulnerabilities in an application, which could be exploited by malicious users. In this paper, we present Stacy—a tool that statically detects potential security vulnerabilities present in input source code. Static program analysis is the examination of source code prior to its execution. Our tool attempts to predict the behavior of a program before it is deployed. Stacy uses novel techniques to detect the primary sources of vulnerability in the source code of a program and informs the developer. [ABSTRACT FROM AUTHOR]

This article responds to Professor Berry's points about the appropriate test of significance of gamma. His remarks do not alter the findings or conclusions of the author's paper. The crucial question involves those relationships which the author reported as nonsignificant and which therefore led the author to explore alternatives. Professor Berry suggests that an appropriate test of significance may have revealed a significant relationship between occupational and religious mobility. But clearly the chi-square is the appropriate test in the case, for the categories are mobility and nonmobility. The former category can be broken down further into upward and downward mobility. No relationship was found between occupational and religious mobility per se.

Background: Inequalities in health represent a major problem in many countries, including Indonesia. Addressing health inequality is a central component of the Sustainable Development Goals and a priority of the World Health Organization (WHO). WHO provides technical support for health inequality monitoring among its member states. Following a capacity-building workshop in the WHO South-East Asia Region in 2014, Indonesia expressed interest in incorporating health-inequality monitoring into its national health information system. Objectives: This article details the capacity-building process for national health inequality monitoring in Indonesia, discusses successes and challenges, and how this process may be adapted and implemented in other countries/settings. Methods: We outline key capacity-building activities undertaken between April 2016 and December 2017 in Indonesia and present the four key outcomes of this process. Results: The capacity-building process entailed a series of workshops, meetings, activities, and processes undertaken between April 2016 and December 2017. At each stage, a range of stakeholders with access to the relevant data and capacity for data analysis, interpretation and reporting was engaged with, under the stewardship of state agencies. Key steps to strengthening health inequality monitoring included capacity building in (1) identification of the health topics/areas of interest, (2) mapping data sources and identifying gaps, (3) conducting equity analyses using raw datasets, and (4) interpreting and reporting inequality results. As a result, Indonesia developed its first national report on the state of health inequality. A number of peer-reviewed manuscripts on various aspects of health inequality in Indonesia have also been developed. Conclusions: The capacity-building process undertaken in Indonesia is designed to be adaptable to other contexts. Capacity building for health inequality monitoring among countries is a critical step for strengthening equity-oriented national health information systems and eventually tackling health inequities. [ABSTRACT FROM AUTHOR]

In this paper we are concerned with inferences from a sample survey to a finite population. We contrast inferences that are dependent on an assumed model with inferences based on the randomization induced by the sample selection plan. Randomization consistency for finite population estimators is defined and adopted as a requirement of probability sampling. A numerical example is examined to illustrate the dangers in the use of model-dependent estimators even when the model is apparently consonant with the sample data. The paper concludes with a summary of principles that we believe should guide the practitioner of sample surveys of finite populations. [ABSTRACT FROM AUTHOR]

In this article, the author comments on the research paper of John J. Wiorkowski titled "Estimating Volumes of Remaining Fossil Fuel Resources: A Critical Review," published in the September 1981 issue of "Journal of the American Statistical Association." According to the author, the strength of Wiorkowski's paper is in bringing the important problem of petroleum resource estimation to the attention of statisticians. The major weaknesses are in the organization and classification of models and the gaps in coverage. The major issues in resource estimation that Wiorkowski discusses are models for estimating the total oil and gas remaining to be found and a closely related problem, estimating the amount of appreciation in known fields. The problem with the discussion of the models is the lack of a proper classification scheme. Although Wiorkowski mentions the model of researchers E. Barouch and G.M. Kaufman, he fails to note that it is one of a general class of models that are based on the discovery process and fails to emphasize that it is a play model, whereas the others he discusses are used at a higher level of aggregation.

The article presents the author's comments on paper by researcher D. Basu related to randomization analysis of experimental data. Basu writes entertainingly, perhaps, but not informatively. Basu's paper discusses prerandomization, postrandomization, and unrecorded randomization. This discussion is irrelevant. But it is useful, perhaps, to make a remark. It also discusses the sufficiency principle. As Basu has written, this is a data-reduction principle. Basu also discusses researcher R.A. Fisher randomization test. It is obvious that the population in a randomization test of a randomized experiment is "the product of the statistician's imagination." With respect to Basu's writing on "the physical act of randomization," the author believes Basu is merely plain wrong. The paper also describes randomized pair trial. In his paper, Basu gives a hypothetical interchange of a statistician and a scientist and the author. The author suggests that this serves no useful purpose. The author finds the lack of knowledge that underlies Basu's thesis rather surprising, incongruous, and deplorable.

The author is pleased to discuss a paper on the estimation of probability density functions and the location of bumps. There is an extensive literature on density estimation, but many statisticians seem doubtful about the usefulness of these techniques because their application seems subjective and complicated. A major criticism the author would make of this paper is that it does not help to dispel this negative attitude of statisticians toward density estimation. One cannot help but be impressed by the ingenuity of I. J. Good and R. A. Gaskins and even to believe that they may be able to successfully fit probability densities to data. The existence of bumps at the extremes of a sample can be investigated for large sample sizes by treating the bottom and top ends of the original sample as two new samples to be analyzed by themselves. Statistical scientists should heed the flippant advice of Sir Arthur Eddington: "Never trust an experimental result until it has been confirmed by theory."

This paper explores the relation between regional shape geometry and internal regional geometry affiliated with spatial interaction. Because properties of these two geometries are difficult to measure, various indices are calculated. Using the canonical correlation technique, the study then analyzes the relationship between these two geometries. This yields two interesting findings: (1) that relationship does exist between the two types of geometry, and (2) that a connectivity matrix depicting geographic configuration can, in part, measure the regional shape involved. The research employs data for the journey to work in 24 selected Canadian urban areas. [ABSTRACT FROM AUTHOR]

Discusses the role of Fred K. Schaefer in the development of the science of geography. Family background; Graduation at the Kaiser Friedrich Real Gymnasium in 1927; Postgraduate studies at the University of Berlin from 1928 to 1932; Work as a statistician; Political refuge in London when the Nazis came to power; Migration to the United States in 1938; Staff member at the State University of Iowa; Famous article, "Exceptionalism in Geography: A Methodological Examination".

Costner (1965) showed that many of the most commonly used measures of association may be conceptually interpreted as indicating proportional reduction in prediction error. But because it is verbally cumbersome, and conceptually complex for some measures, the proportional reduction in error interpretation has not been widely incorporated in research reports where appropriate. Instead, measures of association continue to be interpreted in abstract terms distinguishing between broad levels of strength. This paper demonstrates that all proportional reduction in error measures of association may be alternately interpreted as indicating the percent of variation explained. Because this interpretation is conceptually meaningful in a manner highly relevant for scientific investigation, more convenient to apply in research reports, and already familiar to most social scientists, it is argued that it be standardly applied to all proportional reduction in error measures. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to introduce a certain modification to the technique of ridge analysis. The standard ridge analysis is employed in order to find conditions on a set of design variables that maximize (or minimize) an estimated second order response function on spheres of varying radii. See for example [3], [4], and [6]. The standard ridge analysis does not account for the fact that the experimental design (or lack of design) might result in large fluctuations in the variance of the predicted response on a sphere of a given radius. Thus the technique might well produce poor estimates of maximum responses and also conditions that give rise to it. Obviously one can expect the difficulty when non-rotatable designs are used to estimate the second order function. In this paper the precision of the predicted response is given a serious consideration in the search for optimum operating conditions. We consider two cases, one in which the variance contours are ellipsoidal, and the more general (and perhaps more typical) experimental situation in which there is no systematic experimental design. In the latter case, the suggested modification is to reduce the influence of the variance of the predicted response by restraining a certain portion of it, that which corresponds to the smallest eigenvalue of the moment matrix. Examples are given for both the specific and general cases to illustrate the improvement over the standard ridge analysis. [ABSTRACT FROM AUTHOR]

Bayesian techniques are widely used in these days for simultaneous estimation of several parameters in compound decision problems. Often, however, the main objective is to produce an ensemble of parameter estimates whose histogram is in some sense close to the histogram of population parameters. This is for example the situation in subgroup analysis, where the problem is not only to estimate the different components of a parameter vector, but also to identify the parameters that are above, and the others that are below a certain specified cutoff point. We have proposed in this paper Bayes estimates in a very general context that meet this need. These estimates are obtained by matching the first two moments of the histogram of the estimates, and the posterior expectations of the first two moments of the histogram of the parameters, and minimizing, subject to these conditions, the posterior expectation of the Euclidean distance between the estimates and the parameters. Several applications of the main result are provided in the normal and other models. Also, the results are applied to an actual data set. [ABSTRACT FROM AUTHOR]

This article comments on a paper by Roderick J. A. Little which discussed a method of imputation that is a mixture of model-based and nearest neighbor ideas. The matching is based on the predictions of missing values, but the actual imputations are from the matching record identified. Problems arise with this idea because the match is done on the predictions, not the predictors, and implies a great deal of faith in the model that one is using. Certainly, one would have to check out the predictive efficiency of a model before proceeding with this method. One positive feature is that some of the predictors could be non-numeric, whereas the distance function is expressed in terms of the numeric predictions only. Another concern with this method is that the constraints on the data are not taken care of. Little does refer to this problem, but he appears to hope that it is a minor. Since the predicted variables are used only to define a match, the actual imputed variables are used only to define a match, the actual imputed values, since they come from a single valid record response, will be consistent among themselves. With the idea of multiple imputation comes the notion of repeating the analysis under different imputation scenarios. The sensitivity of the analysis to the missing data could then be assessed, assuming the means to generate appropriate measures of variability were available. The potential for generating vast quantities of paper is enormous. More seriously, analysts would have to learn to describe the procedures and report results in this multiple format.

The article comments on the research paper "Basic statistical considerations for occupational and environmental physiology: the Temperature toolbox" by A. R. Caldwell and S. N. Cheuvront in the current issue of the journal. Topics include the paper goes without saying that experimental design, data collection, data analysis, and dissemination of results are important and their review being a guide for physiologists to avoid common pitfalls and mistakes as they plan and analyze their studies.

This study compares and correlates young and elderly people's pinch force and endurance, and proposes inventive solutions contextualised from these statistical evaluations using TRIZ techniques. An experiment was performed with 64 young and old adults who were required to pinch an apparatus while wearing a glove with pressure sensors. Participants held their pinch until they could no longer sustain it. Pinch force and endurance time were measured and analysed using Pearson's correlation and T-Tests. The analyses confirmed that pinch force decreases with lower endurance and vice versa. Apart from the significant difference in elderly and young people's pinch force and endurance, researchers found that young people sustained pinches longer and at a higher force than elderly people. TRIZ strategies suggested that it is better for objects to 'grasp' the elderly's fingers in pinch activities rather than the usual way. Elderly people could attempt pinching periodically to conserve endurance and reduce injury risks from highly sustained exertions. This study provides an explicit pathway in developing innovative solutions that help prevent finger-related musculoskeletal risks among elderly people. These solutions have the potential in contributing to advances in ergonomics, mechanical design and biomechanics in the form of hand prosthetics and hand exoskeletons. [ABSTRACT FROM AUTHOR]

The objective of this study was to examine sexual orientation-based disparities in six self-reported health outcomes among millennial aged military veterans. We collected data using The Millennial Veteran Health Study, a cross-sectional internet-based survey with extensive quality control measures. The survey was fielded April through December 2020 and targeted millennial aged veterans across the United States. A total of 680 eligible respondents completed the survey. We assessed six binary health outcomes: alcohol use, marijuana use, frequent chronic pain, opioid misuse, high psychological distress, and fair or poor health status. Using logistic regression adjusted for a range of demographic, socioeconomic, and military-based covariates, we find that bisexual veterans consistently report worse health than straight veterans for all six health outcomes tested. Results for gay or lesbian, compared to straight veterans, were less consistent. Sensitivity models with continuous outcomes, and stratified by gender, found similar results. These results have implications for improving the health of bisexual individuals, including addressing discrimination, belonging, and social identity, particularly in institutional settings that have traditionally heteronormative and masculine cultures such as the military. [ABSTRACT FROM AUTHOR]

Can a "nudge" toward engaging, fun, and useful material improve student attitudes toward statistics? We report on the results of a randomized study to assess the effect of a "nudge" delivered via a weekly E-mail digest on the attitudes of students enrolled in a large introductory statistics course taught in both flipped and fully online formats. Students were randomized to receive either a personalized weekly E-mail digest with course information and a "nudge" to read and explore interesting applications of statistics relevant to the weekly course material, or a generic course E-mail digest with the same course information, and no "nudge." Our study found no evidence that "nudging" students to read and explore interesting applications of statistics resulted in better attitudes toward statistics. for this article are available online. [ABSTRACT FROM AUTHOR]

In K–12 statistics education, there is a call to integrate statistics content standards throughout a mathematics curriculum and to teach these standards from a data analytic perspective. Annotated lesson notes within a lesson plan are a freely available resource to provide teachers support when navigating potentially unfamiliar statistics content and teaching practices. We identified several types of annotated lesson notes, created two statistics lesson plans that contained various annotated lesson notes, and observed secondary mathematics teachers implement the lesson plans in their intermediate algebra courses. For this study, we qualitatively investigated how two teachers' instructional actions compared to what was prescribed in the annotated lesson notes. We found ways in which the teachers' instructional actions, across their differing contexts, aligned with, varied from, or adapted to the annotated lesson notes. From these results, we highlight affordances and limitations of annotated lesson notes for statistics instruction and offer recommendations for those who create statistics curricula with annotated lesson notes. [ABSTRACT FROM AUTHOR]

Being a teacher or a student in a class with a large enrollment can be intimidating. Often, teachers view comforts that are common to small classes as unattainable in a larger class, including knowing students' names, using active learning, employing group work, and creating group discussion. Students in large classes may find that the class size leads to isolation. At Utah State University, we offer introductory statistics classes for various audiences using a large lecture format. The authors have collectively led these large lectures dozens of times and found that, despite its shortcomings, the large lecture format can be an asset when teaching statistics. With an active learning approach such as recommended by the revised GAISE College report, large class sizes permit realistic sampling, facilitate student-driven simulation, and provide bountiful opportunities for experimentation. In this article, we discuss the benefits of large classes for statistics teaching and present examples of using large class sizes to create an engaging environment that where students are involved in active learning and collecting real data to foster statistical thinking. [ABSTRACT FROM AUTHOR]

In many of statistical theory of asymptotic distribution, it is based on normal distribution or some parameters that it is difficult to determine. In this paper we consider combined Poisson distribution and introduce one of the theoretical approach that does not require much of them to obtain more convenience, instead by using inequality of best estimate. [ABSTRACT FROM AUTHOR]

In this paper, we review some results for insurance risk theory. We first introduce a variety of the insurance risk models proposed thus far. Then, we show that the expected discounted penalty function (the so-called Gerber-Shiu function) can describe some risk indicators. Next, the dividend problem is discussed; more precisely, the (approximated) optimal dividend barrier is derived and other extended dividend strategies introduced. In addition, some modified models depending on reinsurance or tax are introduced. Finally, we discuss the statistical estimation of the ruin probability and the Gerber-Shiu function. [ABSTRACT FROM AUTHOR]

As it is known that the hybrid Fibre Reinforced Polymer (FRP) composite laminate is a recently evolved class of structural material. Hence, the present work deals with secondary processing ability like hole drilling on hard to machine FRP laminate. The influence of drilling attributes on the delamination factor and surface roughness contours are studied for a high thickness hybrid (carbon/glass FRP) laminates. Here, the experimentation was performed utilising Taguchi's L27 design of experiments array. Later, on post-drilling, the predominant and optimum variables were studied through taguchi and variance analysis to highlight their contribution on the response functions. Taguchi results indicate that the combination of the 90՞tungsten carbide tool, speed of 800 rpm, and rate of feed 50 mm/min gives the best performance concerning the delamination. Also, it was observed that the combination of the 118՞tungsten carbide tool, cutting speed of 900 rpm and the rate of feed 60 mm/min give the best performance concerning surface roughness. Whereas, as per ANOVA, the highest percentage contribution factor was concerned to a tool material followed by other factors and analysed data lie with the confidence level of 95%. The work also indicates that tungsten carbide tool yield better results compared to high-speed steel tool. Further, fibre morphology has been studied, which indicates optimal structure with minimal damage. [ABSTRACT FROM AUTHOR]

There is an ongoing controversy about women's sexuality and the existence of different orgasms. The debate is tilted toward anatomical and physiological evidence, which often leaves subjective experiences out of the picture. The aim of the current mixed-methods study was to capture women's accounts of their experiences of orgasmic states. As part of a larger online survey, 513 women (M = 25.89 years, SD = 5.60) from a community sample filled in open-ended questions on their experience of different kinds of orgasms. Additionally, women rated semantic differentials with bipolar adjectives characterizing vaginal and clitoral orgasms. A sub-sample of n = 257 women (50%) had experienced both, vaginal and clitoral orgasms and rated both separately on the semantic differential. Wilcoxon signed-rank test showed significant differences in that clitoral orgasms were, amongst others, rated as sharper, easier, and more controllable, while vaginal orgasms were rated as wilder, deeper, more pulsating, and extending. In open-ended questions, women talked about various other orgasmic experiences, such as mixed clitoral/vaginal orgasms, whole body, cervical, anal, or mental orgasms. Some women were uncertain about their orgasmic experiences. It is time to integrate anatomical, psychophysiological, and experiential data and conclude that either "all clitoral" or "clitoral and vaginal" falls short to do justice to the complexity of women's orgasms. Understanding and defining these various types of orgasms and allowing for the apparent diversity to have its place in research and in social discourse is a task for future research and pleasure-positive sex education to increase pleasure literacy. [ABSTRACT FROM AUTHOR]

Preeclampsia (PE) presence could lead to hemodynamic changes. Previous research suggested that morphological parameters based on photoplethysmographic pulse waves (PPGW) could help diagnose PE. To investigate the performance of a novel PPGPW-based parameter, falling scaled slope (FSS), in distinguishing PE. To investigate the advantages of the machine learning algorithm over the conventional statistical methods in the analysis. Eighty-one pieces of PPGPW data were acquired for the study (PE, n = 44; normotensive, n = 37). The FSS values were calculated and used to construct a PE classifier using the K-nearest neighbors (KNN) algorithm. A predicted PE state varying from 0 to 1 was also calculated. The classifier's performance in distinguishing PE was evaluated using the ROC and AUC. A comparison was conducted with previously published PPGPW-based models. Compared to the previous PPGPW-based parameters, FSS showed a better performance in distinguishing PE with an AUC value of 0.924, the best threshold of 0.498 could predict PE with a sensitivity of 84.1% and a specificity of 89.2%. As for the analysis method, training a classifier using the KNN algorithm had an advantage over the conventional statistical methods with the AUC values of 0.878 and 0.749, respectively. The result indicated that FSS might be an effective tool for identifying PE. Moreover, the machine learning algorithm could further help the data analysis and improve performance. [ABSTRACT FROM AUTHOR]

Probability distribution functions (PDFs) of atmospheric reentry latitude predictions are shown to be bimodal for spacecraft in low-eccentricity, prograde low Earth orbits at altitudes of 300 km and lower. Using two-line element (TLE) data for initial orbit conditions, coupled with coarse estimates for spacecraft aerodynamic characteristics, parametric simulations produce bimodal distributions that suggest a greater likelihood of reentry near the latitudinal maxima of a given spacecraft's ground track. Various computational measures are used to test for and quantify bimodality in the reentry latitude data sets. Also, a method for approximating bandwidth is introduced for the kernel estimation of reentry latitude probability density. Overall, statistical analysis indicates that actual reentry latitudes are generally within 1-σ of observed hemisphere means as demonstrated by six historical reentry cases. [ABSTRACT FROM AUTHOR]

This article comments on a paper by Nozer D. Singpurwalla and Jane M. Booker which aimed to develop a line of argument that demonstrates that probability theory has a sufficiently rich structure for incorporating fuzzy sets within its framework. Google reports about 670,000 websites that connect with the phrase fuzzy logic. From a mathematical perspective, the concept of a fuzzy set is somewhat disconcerting, because a fuzzy set is generally not a set, but rather a variable. A crucial issue, which was debated already in the earliest days of fuzzy logic, concerns whether or not membership values are just probabilities in disguise. Certainly, the original motivating examples deal primarily with formalizing variables that correspond to natural language concepts that are in everyday use. The paper's section 4 introduces Lofti Zadeh's rejection of the law of the excluded middle, with reference to differentiating between membership values and probabilities. The commenter's reading of the paper's section 4, and of formula (1) in particular, suggests that Zadeh in 1968 might well have approved a solution along the lines of the preceding paragraph, except that he would have used the posterior expectation of m(x) as a summary of the posterior distribution.

This article comments on a paper by Nozer D. Singpurwalla and Jane M. Booker which aimed to develop a line of argument that probability theory has a sufficiently rich structure tor incorporating fuzzy sets within its framework. According to the commenter, the paper provides a real advance in the understanding of fuzzy sets, by providing a sensible connection between membership functions and likelihood, and thereby probability. He says the paper's modification of the basic question is answered most convincingly. However, the answer raises an apparent conflict between the two calculi of fuzzy logic and probability. What is now needed is a second article to resolve this conflict. The commenter's conjecture is that the resolution will show that the rules of fuzzy logic are untenable. According to him, his principal reason behind the conjecture is that the rules of the probability calculus follow from simple, obvious assumptions, whereas those of the fuzzy calculus have been arbitrarily selected. He points out that this arbitrariness is fine for a pure mathematician. But, according to him, an applied mathematician, faced with the reality of uncertainty in the real world, must take into account that world and cannot ignore the basic assumptions about uncertainty that underlie the probability calculus and reflect basic truths about the world.

This article presents a response to several commentaries regarding a study which proposed computations for Bayesian p values in composite null models. In the double use of data and conditioning, Michael Evans and Hal S. Stern both discussed what constitutes double use of the data in computing a p value. They take opposite perspectives on this issue. Evans argues that the only way to avoid double use of the data is to separate the data into two independent subsets, using one subset to fit the model and the other to assess the validity of the model. Because the procedures that we recommend do not formally split the data into two parts, Evans suggests that they can be guilty double use of the data. In contrast, Stern does not feel that it is necessary to worry about double use of the data the extent that we worry, he does not feel that even the posterior predictive p value involves double use of the data. These contrasting positions perfectly highlight what we view to be the main motivation for our paper. We feel that it is very important to avoid a double use of the data, but that separating the data into two independent subsets is a too drastic solution that can lose considerable power. We consider each of these issues in turn.

The author offers a commentary on an article by Professors J. Duchi et al which developed packing arguments and perturbation mechanisms for differential privacy in the minimax framework for statistical estimation leading to a range of minimax optimal estimation rates. He discusses the prevalent models for designing differentially private algorithms, how minimax lower bounds are developed, and the attention received by the sequence of papers by the authors in the machine learning community.

In the present article, Dai et al. ([5]) studies FDR control of the GM and DS methods for generalized linear models (GLMs) under a unified framework. Specifically, Xing, Zhao, and Liu ([16]) develops the Gaussian Mirror (GM) method for controlling FDR in high-dimensional linear regressions. Wang and Ramdas ([15]) uses e-value and develops the e-BH procedure to control FDR. With the maturity of data collection techniques, the analysis of data with high-dimensional input is now routinely conducted. [Extracted from the article]

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Prevention capacity of local health organisations is associated with the performance and outcomes in public health. In Colombia, where cardiovascular disease is the leading cause of morbidity and mortality, there is limited knowledge about the capacity of local health departments to prevent this condition. Efforts are needed to address problems, potential solutions and expected outcomes regarding cardiovascular disease. In this study, a conceptual model for cardiovascular disease prevention capacity in Colombian local health departments was developed, a questionnaire based on this model was validated, the overall cardiovascular disease prevention capacity in a subsample of these organisations was measured, and the association between cardiovascular disease prevention capacity and political, population, and organisational factors was examined. Once the acceptable performance of the questionnaire was verified, variability in cardiovascular prevention capacity was found among a subsample of local health departments. Furthermore, this study provides primary evidence regarding the association between the size of local health departments and overall cardiovascular disease prevention capacity in Colombia. Future studies should focus on measuring this capacity on a larger scale and developing, implementing, and evaluating interventions aimed at strengthening cardiovascular prevention capacity in Colombian local jurisdictions. [ABSTRACT FROM AUTHOR]

Globally, anaemia prevails as a public health issue, being also a concern in Mozambique, where about two-thirds of children 6–59 months of age are affected by this condition. We carried out this study to estimate anaemia prevalence and evaluate structural determinants and haematological parameters association among children aged 6–59 months attending pediatric inpatient and outpatient services in a Quaternary Health Facility in Maputo City Province, Mozambique. We collected data from 637 inpatients or outpatients who attended pediatric consultations at the Maputo Central Hospital. The overall rate of anaemia in children aged 6–59 months was 62.2% (396/637), with 30.9% moderate anaemia (197/637), 23.9% mild anaemia (152/637), and 7.4% severe anaemia (47/637). Among our study participants, critical factors for anaemia were those concerning the age group, child´s caregiver schooling, malaria and size of the liver. [ABSTRACT FROM AUTHOR]