bluuebunny/crossref_metadata_2025 huggingface dataset:
Evidence-based review of trauma center care and routine palliative care processes for geriatric trauma patients; A collaboration from the American Association for the Surgery of Trauma Patient Assessment Committee, the American Association for the Surgery of Trauma Geriatric Trauma Committee, and the Eastern Association for the Surgery of Trauma Guidelines Committee
Authors: Aziz Hiba Abdel , Lunde John , Barraco Robert , Como John J. , Cooper Zara , Hayward Thomas , Hwang Franchesca , Lottenberg Lawrence , Mentzer Caleb , Mosenthal Anne , Mukherjee Kaushik , Nash Joshua , Robinson Bryce , Staudenmayer Kristan , Wright Rebecca , Yon James , Crandall Marie
Published: December 2018

BACKGROUND

Despite an aging population and increasing number of geriatric trauma patients annually, gaps in our understanding of best practices for geriatric trauma patients persist. We know that trauma center care improves outcomes for injured patients generally, and palliative care processes can improve outcomes for disease-specific conditions, and our goal was to determine effectiveness of these interventions on outcomes for geriatric trauma patients.

METHODS

A priori questions were created regarding outcomes for patients 65 years or older with respect to care at trauma centers versus nontrauma centers and use of routine palliative care processes. A query of MEDLINE, PubMed, Cochrane Library, and EMBASE was performed. Letters to the editor, case reports, book chapters, and review articles were excluded. GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodology was used to perform a systematic review and create recommendations.

RESULTS

We reviewed seven articles relevant to trauma center care and nine articles reporting results on palliative care processes as they related to geriatric trauma patients. Given data quality and limitations, we conditionally recommend trauma center care for the severely injured geriatric trauma patients but are unable to make a recommendation on the question of routine palliative care processes for geriatric trauma patients.

CONCLUSIONS

As our older adult population increases, injured geriatric patients will continue to pose challenges for care, such as comorbidities or frailty. We found that trauma center care was associated with improved outcomes for geriatric trauma patients in most studies and that utilization of early palliative care consultations was generally associated with improved secondary outcomes, such as length of stay; however, inconsistency and imprecision prevented us from making a clear recommendation for this question. As caregivers, we should ensure adequate support for trauma systems and palliative care processes in our institutions and communities and continue to support robust research to study these and other aspects of geriatric trauma.

LEVEL OF EVIDENCE

Systematic review/guideline, level III.
Development of a geospatial approach for the quantitative analysis of trauma center access
Authors: Winchell Robert J. , Xu Paige , Mount Lauren E. , Huegerich Reed
Published: December 2018

INTRODUCTION

Decisions around trauma center (TC) designation have become contentious in many areas. There is no consensus regarding the ideal number and location of TC and no accepted metrics to assess the effect of changes in system structure. We aimed to develop metrics of TC access, using publicly available data and analytic tools. We hypothesize that geospatial analysis can provide a reproducible approach to quantitatively asses potential changes in trauma system structure.

METHODS

A region in New York State was chosen for evaluation. Geospatial data and analytic tools in ArcGIS Online were used. Transport time polygons were created around TC, and the population covered was estimated by summing the census tracts within these polygons. Transport time from each census tract to the nearest TC was calculated. The baseline model includes the single designated TC. Model 1 includes one additional TC, and Model 2 includes two additional TC, chosen to maximize coverage. The population covered, population-weighted distribution of transport times, and population covered by a specific TC were calculated for each model.

RESULTS

The baseline model covered 1.12 × 106 people. The median transport time was 19.2 minutes. In Model 1, the population covered increased by 14.4%, while the population catchment, and thus the estimated trauma volume, of the existing TC decreased by 12%. Median transport time to the nearest TC increased to 20.4 minutes. Model 2 increased coverage by 18% above baseline, while the catchment, and thus the estimated trauma volume, of the existing TC decreased by 22%. Median transport time to the nearest TC decreased to 19.6 minutes.

CONCLUSIONS

Geospatial analysis can provide objective measures of population access to trauma care. The analysis can be performed using different numbers and locations of TC, allowing direct comparison of changes in coverage and impact on existing centers. This type of data is essential for guiding difficult decisions regarding trauma system design.

LEVEL OF EVIDENCE

Care management, level IV.
Redistribution of proteasomes through diffusion and cytoskeleton-dependent mechanisms upon stress induced by protein aggregates
Authors: Morten Michael J , Zhang Yu , Li Bing , Meng Jonathan X , Jiang Kun , Sirvio Liina , Lee Ji Eun , Lippert Anna Helena , Burridge Matilda , Pulgar Prieto Katiuska Daniela , Carr Alexander Roy , Ponjavic Aleks , Lee Steven F , Finley Daniel , Klenerman David , Ye Yu
Published: December 2018

Proteasomes are abundant molecular machines distributed throughout the eukaryotic cell to facilitate protein degradation. We previously showed that proteasomes can re-organize and assemble into foci bodies in response to proteotoxic stress1, which we termed transient aggregate-associated droplets (TAADs)2. Here, we use single-molecule localization microscopy to quantify re-organization of mammalian proteasomes in different subcellular regions during proteotoxic stress to engage with invading protein aggregates. We determine that ∼60% of 20S proteasomes are capped by at least one 19S particle, and this ratio remains constant during stress. Using single-particle tracking, we show that cells confine global proteasomal movement when experiencing proteotoxic stress via a cytoskeleton-dependent mechanism. Similar limitations on proteasome movement are also observed upon membrane depolarization and repolarization events by patch clamp, which directly induce proteasomes to move away or towards the plasma membrane, respectively. Together, our experiments reveal distinct modes of proteasome motion dependent on cellular requirements, and propose that proteasome transport is restricted upon aggregate invasion to facilitate their subsequent degradation.
Dynamic adaptive X-ray optics. Part II. High-speed piezoelectric bimorph deformable Kirkpatrick–Baez mirrors for rapid variation of the 2D size and shape of X-ray beams
Authors: Alcock Simon G. , Nistea Ioana-Theodora , Signorato Riccardo , Owen Robin L. , Axford Daniel , Sutter John P. , Foster Andrew , Sawhney Kawal
Published: December 2018

The tangential curvature of actively bent X-ray mirrors at synchrotron radiation and X-ray free-electron laser (XFEL) facilities is typically only changed every few hours or even days. This operation can take tens of minutes for active optics with multiple bending actuators and often requires expert guidance using in situ monitoring devices. Hence, the dynamic performance of active X-ray optics for synchrotron beamlines has historically not been exploited. This is in stark contrast to many other scientific fields. However, many areas of synchrotron radiation and XFEL science, including macromolecular crystallography, could greatly benefit from the ability to change the size and shape of the X-ray beam rapidly and continuously. The advantages of this innovative approach are twofold: a large reduction in the dead time required to change the size of the X-ray beam for different-sized samples and the possibility of making multiple changes to the beam during the measurement of a single sample. In the preceding paper [Part I; Alcock, Nistea, Signorato & Sawhney (2019), J. Synchrotron Rad.
26, 36–44], which accompanies this article, high-speed visible-light Fizeau interferometry was used to identify the factors which influence the dynamic bending behaviour of piezoelectric bimorph deformable X-ray mirrors. Building upon this ex situ metrology study, provided here is the first synchrotron radiation beamline implementation of high-speed adaptive X-ray optics using two bimorphs operating as a Kirkpatrick–Baez pair. With optimized substrates, novel opto-mechanical holders and a next-generation high-voltage power supply, the size of an X-ray beam was rapidly and repeatedly switched in <10 s. Of equal importance, it is also shown that compensation of piezoelectric creep ensures that the X-ray beam size remains stable for more than 1 h after making a major change. The era of high-speed adaptive X-ray optics for synchrotron radiation and XFEL beamlines has begun.
The Moon Jae-in administration’s North Korea policy and Korea–US relations
Authors: Kyu Nam Kwang
Published: December 2018

Purpose

The purpose of this paper is to present the North Korea policy pursued by the Moon Jae-in administration and discuss the possibility of a weakened alliance between South Korea and the USA.

Design/methodology/approach

This paper compares the North Korean policies and the ROK–US alliance under the Moon administration, analyzing the recent inter-Korean and North Korea–US summits, with a focus on the issues of denuclearization and establishing a peace regime.

Findings

This paper reveals that the approach taken by the Moon administration regarding North Korea is similar to that of North Korea and China, and that the ROK–US alliance is likely to weaken should there be any change concerning the North Korean nuclear issue.

Originality/value

Denuclearization takes place in accordance with the agreement between North Korea and the USA, there is a high likelihood of the ROK–US alliance weakening.
The influence of integrated reporting and internationalisation on intellectual capital disclosures
Authors: Terblanche Wendy , De Villiers Charl
Published: December 2018

Purpose

The purpose of this paper is to examine whether preparing an integrated report and/or whether cross-listing is associated with more intellectual capital (IC) disclosure.

Design/methodology/approach

The paper compares the content of IC disclosures of matched samples of companies.

Findings

The findings show that companies preparing an integrated report disclose more IC information, and that companies exposed to international capital market pressures through cross-listing do not disclose more IC information.

Research limitations/implications

The findings imply that integrated reporting (IR) is likely to increase IC disclosures and also that future IC disclosure research may have to take into account whether companies prepare an integrated report.

Practical implications

The results will be of interest to the proponents of IC and of IR, including the developers of the IR framework, regulators and companies considering IR.

Originality/value

This is one of the first studies to assess the influence of preparing an integrated report on the level of IC disclosure.
Visualizing community pride: engaging community through photo- and video-voice methods
Authors: Li Eric Ping Hung , Prasad Ajnesh , Smith Cristalle , Gutierrez Ana , Lewis Emily , Brown Betty
Published: December 2018

Purpose

The purpose of this paper is to consider the potential of visual (i.e. non-textual) research methods in community-based participatory research.

Design/methodology/approach

The authors draw on a case illustration of a photo- and video-voice campaign involving rural communities in British Columbia, Canada.

Findings

The authors find that visual research methods, in the form of photo- and video-voice campaigns, allow participants to form ties between their community and the broader sociocultural, natural and political milieu in which their community is located. The authors highlight the benefits of using such methodological approaches to capture an emic perspective of community building.

Originality/value

The contribution of this study is twofold. First, this study uses a photo- and video-voice campaign to showcase the role of visuals in articulating community pride – that is, how locals construct identity – and a sense of belongingness. Second, by focusing its analytical gaze on the idea of “community,” this paper revisits the importance of active involvement of research participants in the execution of empirical studies. Ultimately, the authors urge organization and management studies scholars, as well as those working in the social sciences more broadly, to further explore the value of innovative community-based research approaches in future work.
Using hidden Markov models to model spatial dependence in a network
Authors: Kadhem Safaa. K. , Hewson Paul , Kaimi Irene
Published: December 2018

This study considers spatial dependence in the number of injury crashes reported on a road network. The aggregated crash counts are considered realisations of a Poisson random variable; thus, we model both over‐dispersion and serial correlation using the Poisson hidden Markov model (PHMM). PHMMs have typically been used for modelling temporal dependence, but they have rarely been used to model spatial dependence. Our interest, however, is specifically in relation to an underlying point process which is constrained to occur on a network. We illustrate the use of the PHMM with police‐reported data on injury road collisions on selected motorways in the United Kingdom over a 5‐year period (2010–2014). We use officially recorded estimates of traffic volume as an exposure variable. The aim is to identify highway segments which might have distinctly high crash rates. To do this, we first select an optimal model in terms of the number of latent states. As we use a Bayesian approach, we can assign a posterior classification probability to each segment in terms of membership of the various underlying risk states. Model fitting is conducted using the Markov chain Monte Carlo approach; we develop a new modified version of the Akaike Information Criterion and Bayesian Information Criterion, approximated from a Bayesian framework, to select the best model in terms of number of states.
Elucidation of the d‐lysine biosynthetic pathway in the hyperthermophile Thermotoga maritima
Authors: Miyamoto Tetsuya , Katane Masumi , Saitoh Yasuaki , Sekine Masae , Homma Hiroshi
Published: December 2018

Various d‐amino acids are involved in peptidoglycan and biofilm metabolism in bacteria, suggesting that these compounds are necessary for successful adaptation to environmental changes. In addition to the conventional d‐alanine (d‐Ala) and d‐glutamate, the peptidoglycan of the hyperthermophilic bacterium Thermotoga maritima contains both l‐lysine (l‐Lys) and d‐Lys, but not meso‐diaminopimelate (meso‐Dpm). d‐Lys is an uncommon component of peptidoglycan, and its biosynthetic pathway remains unclear. In this study, we identified and characterized a novel Lys racemase (TM1597) and Dpm epimerase (TM1522) associated with the d‐Lys biosynthetic pathway in T. maritima. The Lys racemase had a dimeric structure containing pyridoxal 5′‐phosphate as a cofactor. Among the amino acids, it exhibited the highest racemase activity toward d‐ and l‐Lys, and also had relatively high activity toward d‐ and l‐enantiomers of ornithine and Ala. The Dpm epimerase had the highest epimerization activity toward ll‐ and meso‐Dpm, and also measurably racemized certain amino acids, including Lys. These results suggest that Lys racemase contributes to production of d‐Lys and d‐Ala for use as peptidoglycan components, and that Dpm epimerase converts ll‐Dpm to meso‐Dpm, a precursor in the l‐Lys biosynthetic pathway.
Novel approach to improve progesterone hydroxylation selectivity by CYP106A2 via rational design of adrenodoxin binding
Authors: Sagadin Tanja , Riehm Jan , Putkaradze Natalia , Hutter Michael C. , Bernhardt Rita
Published: December 2018

Bacterial P450s have considerable potential for biotechnological applications. The P450 CYP106A2 from Bacillus megaterium ATCC 13368 converts progesterone to several hydroxylated products that are important precursors for pharmaceutical substances. As high yields of monohydroxylated products are required for biotechnological processes, improving this conversion is of considerable interest. It has previously been shown that the binding mode of the redox partner can affect the selectivity of the progesterone hydroxylation, being more stringent in case of the Etp1 compared with Adx(4–108). Therefore, in this study we aimed to improve hydroxylation selectivity by optimizing the binding of Adx(4–108) with CYP106A2 allowing for a shorter distance between both redox centers. To change the putative binding interface of Adx(4–108) with CYP106A2, molecular docking was used to choose mutation sites for alteration. Mutants at positions Y82 and P108 of Adx were produced and investigated, and confirmed our hypothesis. Protein–protein docking, as well as conversion studies, using the mutants demonstrated that the iron–sulfur(FeS) cluster/heme distance diminished significantly, which subsequently led to an approximately 2.5‐fold increase in 15β‐hydroxyprogesterone, the main product of progesterone conversion by CYP106A2.
Initiation of advance care planning in newly admitted nursing home residents in Flanders, Belgium: A prospective cohort study
Authors: Paque Kristel , Ivanova Ivana , Elseviers Monique , Stichele Robert Vander , Dilles Tinne , Pardon Koen , Deliens Luc , Christiaens Thierry
Published: December 2018

Aim

To describe (i) the timing of initiation of advance care planning (ACP) after nursing home admission; (ii) the association of dementia and physical health with ACP initiation; and (iii) if and how analgesic use and use of lipid modifying agents is related to ACP, in a cohort of newly admitted residents.

Methods

A prospective, observational cohort study of nursing home residents was carried out. Data were collected 3 months, 15 months (year 1) and 27 months (year 2) after admission, using a structured questionnaire and validated measuring tools.

Results

ACP was never initiated during the 2‐year stay for 38% of the residents, for 22% ACP was initiated at admission, for 21% during year 1 and for 19% during year 2 (n = 323). ACP initiation was strongly associated with dementia, but not with physical health. Residents without dementia were more likely to have ACP initiation at admission or not at all, whereas ACP initiation was postponed for residents with dementia. Between admission and year 2, analgesic use increased (from 34% to 42%), and the use of lipid‐modifying agents decreased (from 28% to 21%). Analgesic use increased more in residents with ACP initiation during year 1 and year 2. The use of lipid‐modifying agents was not associated with ACP.

Conclusions

The timing of ACP initiation differed significantly for residents with and without dementia, which highlights the importance of an early onset of ACP before residents lose their decision‐making capacity. ACP conversations might create opportunities to discuss adequate pain and other symptom treatment, and deprescribing at the end of life. Geriatr Gerontol Int 2019; 19: 141–146.
Policy mix and the U.S. trade balance
Authors: Adler Gustavo , Osorio Buitron Carolina
Published: December 2018

The strong policy response of the United States to the 2008–2009 financial crisis raised concerns about its spillovers on other countries. The effects of the monetary stimulus received significant attention, while those of fiscal policy were largely overlooked, despite the combined deployment of these two policy instruments. This paper studies the trade spillovers of the post‐crisis policy mix. We find that overall effects were positive in the immediate aftermath of the crisis, reflecting positive spillovers of fiscal policy that outweighed the negative impact of monetary policy. More generally, our results highlight (i) the importance of studying fiscal and monetary policy spillovers jointly, as models with both instruments produce very different (and arguably more accurate) estimates of the effects of fiscal and monetary policy shocks, and (ii) that exchange rate regimes of trading partners are first‐order determinants of the extent of policy spillovers.
The electric vehicle routing problem with shared charging stations
Authors: Koç Çağrı , Jabali Ola , Mendoza Jorge E. , Laporte Gilbert
Published: December 2018

We introduce the electric vehicle routing problem with shared charging stations (E‐VRP‐SCS). The E‐VRP‐SCS extends the electric vehicle routing problem with nonlinear charging function (E‐VRP‐NL) by considering several companies that jointly invest in charging stations (CSs). The objective is to minimize the sum of the fixed opening cost of CSs and the drivers cost. The problem consists of deciding the location and technology of the CSs and building the routes for each company. It is solved by means of a multistart heuristic that performs an adaptive large neighborhood search coupled with the solution of mixed integer linear programs. It also contains a number of advanced efficient procedures tailored to handle specific components of the E‐VRP‐SCS. We perform extensive computational experiments on benchmark instances. We assess the competitiveness of the heuristic on the E‐VRP‐NL and derive 38 new best known solutions. New benchmark results on the E‐VRP‐SCS are presented, solved, and analyzed.
Question and Answer
Authors: van Rest E. D.
Published: December 2018

Readers are invited to submit questions or to deal shortly with points of general interest by supplying both the question and the answer.
A Comparison of Gaussian and Logistic Categorical Opinion Distribution Models
Authors: McKenzie John
Published: December 2018

Four models for the analysis of categorical opinion data are described and compared. These include the Successive Intervals model of Guilford (1954) and the SLOLT model of Allnatt (1973), and utilize an underlying continuous opinion distribution which is either Gaussian or logistic. Efficient and semi-efficient estimation schemes are presented. The fits of the models to two sets of data are compared, and the hypothesis of “equal underlying variances” is investigated.
On Least Squares Fitting by Orthonormal Polynomials Using the Choleski Method
Authors: Rushton S.
Published: December 2018

If a set of normal equations, derived from the least squares fitting of a linear representation to a set of observations, is solved by the Choleski method of solving a system of linear simultaneous algebraic equations involving a symmetric matrix, a certain vector is obtained as an intermediate step in the solution. The squares of the elements of this vector are the components in the resolution of the total sum of squares of the observations into squares corresponding to individual degrees of freedom. Each such square represents the contribution corresponding to one of a certain set of orthonormal vectors.

The theory is applied to the fitting of a polynomial to a set of observations, not necessarily equidistant. The appropriate orthonormal polynomials can be derived explicitly and the total sum of squares can be resolved into individual squares corresponding to each of these. A practical computation scheme for this case is given and illustrated by a numerical example.
An Extension Problem in the Theory of Incomplete Block Designs
Authors: Schützenberger M. P.
Published: December 2018

By generalization of concepts of projective geometry, two combinatorial methods have been studied which may allow the extension of a block design into another one. As an application a new infinite family of block designs has been given.
The Interpretation of Interaction in Contingency Tables
Authors: Simpson E. H.
Published: December 2018

The definition of second order interaction in a (2 × 2 × 2) table given by Bartlett is accepted, but it is shown by an example that the vanishing of this second order interaction does not necessarily justify the mechanical procedure of forming the three component 2 × 2 tables and testing each of these for significance by standard methods.
The Estimation of Parameters from Sequentially Sampled Data on a Discrete Distribution
Authors: Tweedie M. C. K.
Published: December 2018

It is supposed that a constant finite discrete population (which may have arisen through grouping another population) is sampled, with replacement, until some linear function of the frequencies reaches a predetermined value. The generating function of the final frequencies is found exactly when each coefficient in the linear function is either 0 or +1, and the asymptotic means, variances and covariances in more general cases by using an extension of Wald’s identity. The approximate first and second moments of estimators of the parameters determining the population based on these final frequencies, can accordingly be found. The information matrix is considered, first as regards the effect on it of grouping, and then as regards the effect of the stop rule used. Different stop rules provide estimators whose second moments depend on the parameters in a variety of different ways, although the average sample size needed for a given minimum amount of information is almost independent of the stop rule. Some simple examples are given.
Goodness of Fit Tests for Simultaneous Autoregressive Series
Authors: Bartlett M. S. , Rajalakshman D. V.
Published: December 2018

The simplified method of derivation of Quenouille’s (1947) goodness of fit test for an autoregressive stationary series with discrete time, given by Bartlett and Diananda (1950), is extended in the present paper to the case of simultaneous autoregressive series, for which some interesting new features arise. The general solution is applied to a particular first-order process in two variables, the detailed correlational theory of which is being given elsewhere by Rajalakshman (1953), and for which artificial series are available for test.
Some Properties of Estimates for the Standard Deviation Based on Deviations from the Mean and Variate Differences
Authors: Kamat A. R.
Published: December 2018

In the first part the property of “minimum error”, proved by Fisher for the estimates based on the powers of the deviations from the mean, is extended to the estimates based on the powers of the absolute values of variate differences. Efficiencies of certain of these statistics are also compared for small samples. In the second part the bias and the variance is evaluated when there is a “slow moving” trend in the mean. Finally in the third part a proof is given of a property possessed by the moments of certain ratio statistics derived from these estimates.
On the Cumulative Effect of Chance Deviations
Authors: Berz F.
Published: December 2018

The cumulative effect of chance deviations is investigated in the case when the components follow rectangular distributions of arbitrary width. The chief aim is to obtain an estimate of the percentage of cases for which the total deviation falls outside given limits, and corresponds to rejects in industrial practice.

The treatment is based on the use of characteristic functions. The results provide a useful quantitative addition to the well-known Central Limit theorem and can easily be applied.
A Note on the Multiplying Factors for Various χ2 Approximations
Authors: Bartlett M. S.
Published: December 2018

A list is given, for reference, of various approximate tests, based on the asymptotic approximations for likelihood ratios, but with adjusted multiplying factors.
Confidence Intervals for the Parameter of a Distribution Admitting a Sufficient Statistic When the Range Depends on the Parameter
Authors: Huzurbazar V. S.
Published: December 2018

This paper gives the sampling distribution of a sufficient statistic (which is also the maximum likelihood statistic) for the parameter of a distribution when the range of the distribution depends upon the parameter. Confidence intervals for the parameter are obtained, based on the distribution of the sufficient statistic.
Economic Choice of the Amount of Experimentation
Authors: Grundy P. M. , Healy M. J. R. , Rees D. H.
Published: December 2018

When a new process is suggested for use in agriculture or technology it is usually necessary to carry out experiments to estimate the increase in output that would result if the new process replaced that in current use. If the cost of experimentation and the scale of potential application of the new process are known, one method of arriving at an optimum amount of experimentation is to minimize the total risk given by the sum of the cost of the experiment plus the expected loss due to wrong decisions. The main difficulty is that the last quantity depends on the true increase in output due to introducing the new treatment, which can only be estimated from the results of the experiments. The paper discusses the case where an initial experiment is carried out, and it is required to decide whether to accept or reject the new treatment at once or else to carry out further experimentation. In the latter case the optimum amount of further experimentation has also to be decided. A solution is provided by minimizing the risk after eliminating the unknown parameter by averaging over its fiducial distribution based on the evidence from the initial experiment. Means for applying the resulting decision rule in practice are provided, and its performance under various circumstances is discussed.
A Test of Significance for an Unidentifiable Relation
Authors: Moran P. A. P.
Published: December 2018

A linear relation between two variates, both of which are measured with error, cannot be identified, but it is possible to identify bounds for its position and slope. It is shown how it is possible to test whether the observed data show a significant divergence from the hypothesis that the linear relation passes through a specified point in the plane. This test is then applied to the relationship between rainfall and run-off.
Tests for Randomness in a Series of Events When the Alternative is a Trend
Authors: Bartholomew D. J.
Published: December 2018

This paper deals with the properties of a test for randomness in a sequence of events occurring in time or space. It was suggested by Cox (1955) as being suitable when the alternative is a trend in the rate at which events occur. The power of the test is compared with that of two other tests which can be used for this purpose.
Expected Arc Length of a Gaussian Process on a Finite Interval
Authors: Miller Irwin , Freund John E.
Published: December 2018

An expression is found for the expected arc length of a stationary Gaussian process.
Sufficient Statistics, Similar Regions and Distribution-Free Tests
Authors: Watson G. S.
Published: December 2018

This paper is mainly an elementary exposition (in §1) of the ideas of Lehmann and Scheffé (1950) concerning sufficient statistics and similar regions. One of the virtues of this elegant theory is the way in which it incorporates some distribution-free tests into the general body of tests based on similar regions—this is described in §3. In §2, its bearing on the Fisher-Behrens and related problems is discussed and a class of problems where it is of no use is suggested. In §4, several new distribution-free tests are given.
Methods of Construction and Analysis of Serially Balanced Sequences
Authors: Sampford M. R.
Published: December 2018

Various methods of construction of Serially Balanced Sequences are described, and sequences obtained by these methods tabulated. The problems of analysis of designs based on the sequences are considered, and general methods derived for certain classes of design.
On Chi-Square Goodness-Of-Fit Tests for Continuous Distributions
Authors: Watson G. S.
Published: December 2018

Suppose that in a chi-squared goodness-of-fit test the unknown parameters are estimated from the likelihood of the continuous observations before grouping. The effect on the distribution of the test criterion is examined.
The Regression Analysis of Binary Sequences
Authors: Cox D. R.
Published: December 2018

A sequence of 0’s and 1’s is observed and it is suspected that the chance that a particular trial is a 1 depends on the value of one or more independent variables. Tests and estimates for such situations are considered, dealing first with problems in which the independent variable is preassigned and then with independent variables that are functions of the sequence. There is a considerable amount of earlier work, which is reviewed.
On the Smoothing of Probability Density Functions
Authors: Whittle P.
Published: December 2018

We consider the estimation of a probability density function by linear smoothing of the observed density. A basis for estimation is obtained by assuming that the ordinates of the true density function have a prior distribution such that adjacent ordinates are highly correlated. An equation determining the optimum weighting function under these circumstances is derived, and solved in special cases. The properties of the estimate are discussed and the asymptotic behaviour of its mean squared deviation D  2 given. It is shown that as the sample size N increases, D  2 cannot decrease faster than N  –1.
The Interaction Algorithm and Practical Fourier Analysis
Authors: Good I. J.
Published: December 2018

The interactions in a complete factorial experiment are linear functions of the observations. They can be calculated by means of a stream-lined algorithm, of which the first example was the adding-and-subtracting algorithm of Yates (1937). The relationship between the two methods of calculating the interactions is given a precise and succinct form, which surprisingly does not seem to have been given in the existing literature. The algorithm is logically simplest for the tn experiment. The inverse algorithm is specified and also the method of obtaining the divisors for the analysis of variance. Finally some analogous short cuts in practical Fourier analysis are described.
On the Distribution of Various Sums of Squares in an Analysis of Variance Table for Different Classifications with Correlated and Non-Homogeneous Errors
Authors: Bhat B. R.
Published: December 2018

The distributions of various sums of squares in an analysis of variance table for two-way classification have been obtained by Box (1954b), under the assumption that the row-vectors X.j(j = 1, 2, …, q) are independent vector observations from a p-variate normal population, where X.j consists of those p observations which correspond to the p levels of a factor A, for the j  th level of another factor B. This paper gives the distributions of the various sums of squares for any n-way classification. It is noted that if the vector observations which correspond to the different levels of r factors for each of the fixed levels of the remaining n — r factors, follow the same multivariate normal law and are mutually independent, the 2n sums of squares (including the correction factor) of the n-way classification can be grouped into 2n—r sets, each of 2r sums of squares with the following properties : (i) the pattern of the null-distribution of the various sums of squares in each set is the same, (ii) the distributions of the various sums of squares within a set are dependent, the sets themselves however being independent.
Censored Observations in Randomized Block Experiments
Authors: Sampford M. R. , Taylor J.
Published: December 2018

Maximum likelihood methods are developed for the analysis of data from randomized block experiments, when some of the observations are censored. A modification of the maximum likelihood process, intended to produce approximately unbiased estimates of variance, is described, and the results of some numerical investigations into its efficacy are reported. Analogues of the t-test, using two alternative formulae for standard errors of differences, are considered, with some results of numerical investigations into the distribution of the t-values.
Control Charts and Stochastic Processes
Authors: Barnard G. A.
Published: December 2018

A new approach to control charts for industrial processes is suggested, based on the idea that the underlying stochastic process should be specified, its parameters estimated, and the control procedure related to these. Optimum estimators are derived, and practical approximations to these are indicated.
A Contribution to the Theory of Bulk Queues
Authors: Miller Rupert G.
Published: December 2018

Two general models for a queue in which groups of entities arrive at a single service line and are serviced in groups are defined. Various equilibrium properties for both models are established in terms of the traffic intensity ρ. For the special case of Poisson arrivals the first model is analyzed with reference to the imbedded Markov chain, the waiting time, and the busy period. It is demonstrated that if the entities arrive in groups the stationary distribution of the imbedded Markov chain does not agree with the general equilibrium distribution obtained by letting time t → ∞. For the special case of exponential service the stationary distribution of the imbedded Markov chain for the second model is obtained and the waiting time problem is discussed briefly.
On the Transient Behaviour of a Simple Queue
Authors: Finch P. D.
Published: December 2018

We consider a single server queue with Poisson arrivals and general distribution of service time and seek to determine the probability distribution of queue size after the nth departure from the system. A generating function is obtained which solves this problem formally. When the service time distribution is negative exponential an explicit solution is obtained.
Bounds for the Expected Sample Size in a Sequential Probability Ratio Test
Authors: Ghosh M. N.
Published: December 2018

The expected sample size in a sequential probability ratio test has been given by Wald (1945, 1947). An approximate value of E(n) with a bound for the error of approximation has also been given by him in the same publication. This bound has been evaluated by Wald (1945) for the normal and binomial distributions and the error is shown to be small when the mean and variance of Z = log {f(x, θ1)/f(x, θ  0)} are small. Wald has mentioned that in general the error of approximation will be small, when the mean and variance of Z are small. An example is given here showing that the error in Wald’s approximate formula for E(n) is not small, even though the mean and variance of Z are small, so that no general statement about the validity of the approximation can be made. In this paper an expression for an upper bound of the error of approximation is given for the general case. For the case of the normal and a class of distributions with similar nature of tails, the random walk problem with variables z1, z2, … is considered where E(z) < 0 and there is only one boundary – b < 0. The expected value of the first passage time n, Zn = z1 + … + zn < – b and Zi ≥ – b for i = 1, 2, …, n – 1, is shown to be bounded and upper bound of E(n) is obtained.
Approximate Solutions of Green's Type for Univariate Stochastic Processes
Authors: Daniels H. E.
Published: December 2018

A study is made of approximations of Green's type (often called W.K.B. approximations) to the solution of equations governing univariate stochastic processes. After considering some specific processes, the general homogeneous process in continuous time is discussed. A numerical comparison is made between the approximate and exact probabilities for the multiplicative birth and death process. Diffusion processes are briefly examined. The method is applied to the equations both for probabilities and for the moment generating function, and the duality between the approximate solutions is indicated. Finally, approximate formulae for the cumulants are obtained and the limitations of the method are pointed out.
Estimation of the Parameters of a Linear Functional Relation
Authors: Dorff Martin , Gurland John
Published: December 2018

A variety of consistent estimators of the parameters of a linear functional relation have been proposed over the years. Some find their basis in least-squares procedures, some in the methods of analysis of variance, some in the method of grouping, and some in diverse other methods. In this paper we generalize a class of estimators suggested originally by the method of grouping, and consider the asymptotic variance of a number of different types of estimators. As a result we are able to make specific recommendations regarding a choice among them.
Optimal Programmes for Varietal Selection
Authors: Curnow R. N.
Published: December 2018

The statistical theory of the sequences of selections that occur in plant breeding programmes is discussed. The emphasis is on numerical results rather than the underlying mathematical theory. The effects of non-normality in the initial distribution of yield on the optimal schemes already proposed for one and two successive selections from a normal distribution are investigated. Other topics considered are the optimal number of varieties to include in a programme involving two successive selections from a normal distribution, the effect of varieties × years interactions, the use of information from the first selection stage in the second-stage selection criterion, three successive selections from a normal distribution, the external economy of two successive selections from a normal distribution and the optimal number of selection stages.
Estimation from Quantiles in Destructive Testing
Authors: Stout H. P. , Stern F.
Published: December 2018

The estimation of mean and standard deviation from the values of two quantiles dividing the specimens into three groups has, by previous authors, been made the basis of a quality control system of gauging specimens at two levels. When a specimen may be gauged once only, single gauging, different specimens must be gauged at each level, and the efficiency of the method is reduced.

For a variate normally distributed with mean, μ, and standard deviation, σ, the efficiency of estimation by single gauging of a quantity μ + ασ is calculated, and contour maps drawn to show the variation of this efficiency with the gauge levels, expressed as normal deviate values, for α → 0, α = – 1, α = – 2, α = – 3 and α → – ∞. Maximum efficiency is attained when the gauge levels are set symmetrically about the mean.

Contour maps calculated for a strongly asymmetric case of the gamma distribution show the maximum efficiency of estimation of μ to be 20·6 per cent, and of σ to be 20·0 per cent, while the positioning of the gauge levels for maximum efficiency is now rather critical and the optimum levels are no longer symmetrical about the mean.
Inequalities for First Emptiness Probabilities of a Dam with Ordered Inputs
Authors: Gani J. , Pyke R.
Published: December 2018

This paper considers the probabilities of first emptiness times for a dam fed by certain ordered inputs α  1, …, αp, and subject to a steady-release rule. Simple inequalities are derived, which prove more tractable in practice than the exact probabilities. These are applied to the particular case of two ordered Poisson inputs α  1, α  2. The paper concludes with conditions for the probability that the dam will eventually become empty.
The Estimation of Spectral Densities
Authors: Daniels H. E.
Published: December 2018

A method of estimating spectral densities is developed which uses the data explicitly to help determine the best smoothing procedure. Two techniques are discussed. The first involves polynomial approximations, the second is an interpolation technique which is useful when a limited number of autocorrelations is available. The Gaussian and Laplacian weight functions play important roles in the first and second technique respectively.
Cumulants of Truncated Multinomial Distributions
Authors: Finney D. J.
Published: December 2018

Tallis's recent results for the m.g.f. of the distribution obtained by truncating an n-dimensional normal distribution at fixed points are expressed more concisely in terms of the cumulant generating function.
On Sufficiency and the Exponential Family
Authors: Fraser D. A. S.
Published: December 2018

The use of the likelihood function as the minimal sufficient statistic provides a simple and direct proof of results by Barankin and Katz (1959) and Barankin (1961) concerning minimal sufficient statistics. In Section 2 the likelihood function is used to analyse the effect of sampling on the dimensionality of the sufficient statistic and it provides a simple and transparent proof that fixed dimension for the sufficient statistic is restricted to the exponential family. In Section 3 a class of selected exponential distributions is shown to be complete.
Posterior Distributions for Multivariate Normal Parameters
Authors: Geisser Seymour , Cornfield Jerome
Published: December 2018

A class of Bayes posterior distributions is obtained for the parameters of the multivariate normal distribution. These are compared with their fiducial and confidence counterparts.
On a Property of the Lognormal Distribution
Authors: Heyde C. C.
Published: December 2018

In this paper it is established that the lognormal distribution is not determined by its moments. Some brief comments are made on the set of distributions having the same moments as a lognormal distribution.
Posterior Odds for Multivariate Normal Classifications
Authors: Geisser Seymour
Published: December 2018

A class of Bayesian methods is presented for finding the posterior odds or probability that a particular observation belongs to one of k multivariate normal populations. Solutions are given for various assumptions on the parameters of the k populations as well as for known and unknown prior probabilities. An application to genetics is included.
Simultaneous Confidence Limits for Cross-Product Ratios in Contingency Tables
Authors: Goodman Leo A.
Published: December 2018

Fisher (1962) has proposed a method for obtaining confidence limits for the cross-product ratio in a 2 × 2 table which requires that the user solve a quartic equation. Based on a different mathematical derivation, Cornfield (1956) had proposed a similar method. In the present article, we shall present simpler methods for obtaining confidence limits for the cross-product ratio in a 2 × 2 table, and we shall extend these methods to obtain simultaneous confidence intervals for the r(r - 1) c(c - l)/4 cross-product ratios in an r × c table (or for a subset of them) and also for the relative differences between the corresponding cross-product ratios in K different r × c tables. In addition, we shall present a modification of a method suggested by Gart (1962a) for the 2 × 2 table, and we shall extend the modified method to the r × c table. The methods presented herein are easier to apply than those given in the earlier literature. For the 2 × 2 table, the confidence limits presented herein are asymptotically equivalent to the limits given earlier. When max (r, c, K) > 2, the simultaneous confidence intervals presented herein for the cross-product ratios and for the relative differences between cross-product ratios are asymptotically shorter than the corresponding intervals given by Cornfield (1956), for the usual probability levels. The method proposed herein for studying the relative differences between cross-product ratios in K r × c tables can also be used to supplement the earlier methods of analysis given by Plackett (1962) and Goodman (1963b) for testing the null hypothesis that these differences are all nil.
A Note on the Bartlett Decomposition of a Wishart Matrix
Authors: Kabe D. G.
Published: December 2018

By suitably factorizing the generalized variance, a concise derivation of the Bartlett decomposition of a central Wishart matrix is given. The method is extended to give a decomposition of a p-dimensional non-central Wishart matrix of rank t (≤ p), in terms of a t-dimensional non-central Wishart matrix of rank t, (p - t) independent χ2 variates and 1/2(p - t)(p + t - 1) independent unit normal variates.