bluuebunny/crossref_metadata_2025 huggingface dataset:
Is coronally positioned flap procedure adjunct with enamel matrix derivative or root conditioning a relevant predictor for achieving root coverage? A systemic review
Authors: Cheng Y.‐F. , Chen J.‐W. , Lin S.‐J. , Lu H.‐K.
Published: May 2007

Background and Objective:  This study is a systemic review of coronally positioned flap, coronally positioned flap + chemical root surface conditioning, or coronally positioned flap + enamel matrix derivative (EMD) for the treatment of Miller class I and II gingival recession.

Material and Methods:  All studies available through the Medline database by the end of October 2005 were used. Each study provided mean clinical attachment level, keratinized tissue, probing pocket depth, gingival recession depth and root coverage percentage before and after treatment with coronally positioned flap alone, coronally positioned flap + chemical root surface conditioning , or coronally positioned flap + EMD. Effectiveness was evaluated by comparing the weighted mean average in gingival recession depth, probing pocket depth, clinical attachment level, keratinized tissue and root coverage percentage achieved with the three treatments.

Results:  Seven studies for the coronally positioned flap + EMD group, four studies for the coronally positioned flap + chemical root surface conditioning group, and seven studies for the coronally positioned flap group were retrieved for this weighted mean analysis. The results of clinical attachment level, gingival recession depth, and root coverage percentage in the coronally positioned flap + EMD group were statistically significantly better than the changes in the coronally positioned flap and coronally positioned flap + chemical root surface conditioning group at 6 and 12 mo (p < 0.001). There was no significant difference at the 6‐mo comparison among clinical attachment level, keratinized tissue, probing pocket depth, and gingival recession depth, except in the root coverage percentage for coronally positioned flap and coronally positioned flap + chemical root surface conditioning groups.

Conclusion:  The results suggest that root coverage by the coronally positioned flap and coronally positioned flap + chemical root surface conditioning procedures were unpredictable but became more predictable when the coronally positioned flap procedure was improved by the modification of adding EMD.
Denture loss: an 8‐month study in a community dental setting
Authors: Michaeli Leila , Davis David M. , Foxton Richard
Published: May 2007

Objective:  Lost dentures can be a frustrating scenario for both patients and clinicians. This study aimed to find out where dentures were being lost and the level of assistance patients received with denture care.

Results:  The results showed most dentures were lost in the hospital environment, and in many cases patients were not provided with pots in which to store their dentures or offered help or advice on denture care. The provision of new dentures to this patient group is complicated by the fact that in many cases the dentures were over ten years old and many of the patients were over eighty five years old. This makes adaptation to new dentures difficult.

Conclusions:  It is imperative that protocols are developed and staff trained to minimise the risk of lost dentures and improve the standard of denture care.
Electromyographic evaluation of masseter and anterior temporalis muscles in rest position of edentulous patients with temporomandibular disorders, before and after using complete dentures with sliding plates
Authors: Zuccolotto Maria Cristina Candelas , Vitti Mathias , Nóbilo Krunislave Antônio , Regalo Simone Cecílio Hallak , Siéssere Selma , Bataglion César
Published: May 2007

Objectives:  This study was performed with the purpose of investigating electromyographic (EMG) activity of the anterior temporalis and masseter muscles in edentulous individuals with temporomandibular disorder (TMD), before and after using sliding plates on complete dentures in the mandibular rest position.

Background:  Edentulous patients may present TMD, which is characterised by pain in temporomandibular joints, masticatory and neck muscles, uncoordinated and limited mandible movements, joint sounds and an altered occlusal relationship. It is imperative to offer treatment in order to re‐establish stomatognathic system structures before submitting the individual to any definitive restorative treatment.

Materials and methods:  The patients were edentulous for at least 10 years. EMG recordings were made before the insertion of the dentures (0 months) and also after using the sliding plates at the fourth month, 9th month and 12th month, using computerised electromyography K6‐I/ EMG Light Channel Surface. EMG evaluations of the muscles were performed under the following clinical conditions: rest position with dentures (R1), rest position without dentures (R2), rest position with dentures post‐activity (chewing) (R3), rest position without dentures post‐activity (chewing) (R4).

Results:  All patients obtained remission of muscular fatigue and reduced pain in stomatognathic system structures. Temporalis muscle showed significant increase in EMG activity compared with initial values (p < 0.01). Masseter muscles showed significantly lower mean values (p < 0.01) compared with initial values.

Conclusion:  The sliding plates allowed the process of neuromuscular deprogramming, contributing to muscular balance of the masticatory system, and are therefore indicated to be used before the fabrication of definitive complete dentures in patients with TMD.
Edentulousness and associated risk factors in a south Brazilian elderly population
Authors: Colussi Claudia Flemming , De Freitas Sérgio Fernando Torres
Published: May 2007

Aim:  To examine the relationship between edentulousness and the socioeconomic and behavioural variables collected in a cross‐sectional study of an elderly population.

Methods:  The study was conducted on 277 elderly (60 years or older) in the municipality of Biguaçu, Southern Brazil. The oral examinations and questionnaires were conducted by two calibrated dentists. The criteria used followed the WHO and FDI standards.

Results:  Prevalence of edentulousness reached 48.4%. A significant association was found in bivariate analysis for gender, satisfaction with appearance, time since last dental visit, the type of dental service sought in the last 5 years, educational level of the elderly and their children, and age of the elderly. In the multivariate analysis, gender, time since last dental visit and level of education of the elderly were significantly associated with edentulousness.

Conclusions:  Female sex and low educational level were the main risk factors for edentulousness in this population. Although various Brazilian studies suggest a decline in edentulousness in the country, methodologically robust research into edentulousness in Brazil is still limited, demanding further studies into this highly prevalent yet preventable health problem amongst the elderly.
Association of total tooth loss with smoking, drinking alcohol and nutrition in elderly Japanese: analysis of national database
Authors: Hanioka Takashi , Ojima Miki , Tanaka Keiko , Aoyama Hitoshi
Published: May 2007

Objective:  Various factors may be associated with edentulism in elderly people. Association of total tooth loss with smoking, alcohol intake and nutrition in non‐institutionalised elderly Japanese was assessed utilising national database.

Materials and methods:  Records of independent surveys, the Survey of Dental Diseases (SDD) and the National Nutrition Survey (NNS) in 1999 were electronically linked using the household identification number.

Results:  Among the records of 6903 subjects in the SDD and 12 763 subjects in the NNS, 6805 records were successfully linked. Overall, prevalence of total tooth loss in adults was very similar in males and females at approximately 7.0%, and the smoking rate was 47.6% and 9.9% respectively. Total tooth loss was a rare phenomenon (<2%) in age groups of <60 years. According to the multiple logistic regression analysis involving 2200 subjects aged 60 years or older, significant variables were age, current smokers and vitamin C intake in males, and age and current smokers in females. The variable for current drinkers was significant in females but the odds ratio was <1.0. No significant relationship was detected with respect to former smokers and drinkers, body mass index, vitamin E intake and blood glucose level.

Conclusions:  Current smoking was associated with total tooth loss, although smoking rate was low in females. Gender difference in the association was suggestive with respect to drinking alcohol and vitamin C intake.
Pharyngeal actinomycosis: a case report
Authors: Carinci Francesco , Polito Jessica , Pastore Antonio
Published: May 2007

Actinomycetes are saprophytic bacteria of the oral cavity. They can produce a rare, chronic, and suppurative process that usually originates from the teeth and mandible and then involve the cervical region, especially in the sub‐mandibular area.

A case of actinomycosis occurring in the retropharyngeal space in a 74 year‐old man is reported. It arose as a swelling behind the third lower left molar that had no lesion. The patient was treated successfully with antibiotic therapy.

The clinical presentation and management of the case are discussed and the relevant literature is reviewed.
Cloning of type 1 cannabinoid receptor inRana esculentareveals differences between genomic sequence and cDNA
Authors: Meccariello Rosaria , Chianese Rosanna , Cobellis Gilda , Pierantoni Riccardo , Fasano Silvia
Published: May 2007

The endocannabinoid system is a conserved system involved in the modulation of several physiologic processes, from the activity of the central nervous system to reproduction. Type 1 cannabinoid receptor (CNR1) cDNA was cloned from the brain and testis of the anuran amphibian, the frogRana esculenta. Nucleotide identity ranging from 62.6% to 81.9% is observed among vertebrates. The reading frame encoded a protein of 462 amino acids (FCNR1) with all the properties of a membrane G‐coupled receptor. Alignments of FCNR1 with those of other vertebrates revealed amino acid identity ranging from 61.9% to 88.1%; critical domains for CNR1 functionality were conserved in the frog. As nucleotide differences ofcnr1cDNA were observed in brain and testis, the genomic sequence of thecnr1gene was also determined in the same tissue preparations. Nucleotide changes in codons 5, 30, 70, 186, 252 and 408 were observed when cDNA and genomic DNA were compared; the nucleotide differences did not affect the predicted amino acid sequences, except for changes in codons 70 and 408. Interestingly, the predicted RNA folding was strongly affected by different nucleotide sequences. Comparison ofcnr1mRNA sequences available in GenBank with the corresponding genomic sequences revealed that also in human, rat, zebrafish and pufferfish, nucleotide changes between mRNA and genomic sequences occurred. Furthermore, amino acid sequences deduced from both mRNA and the genome were compared among vertebrates, and also in pufferfish the nucleotide changes corresponded to modifications in the amino acid sequence. The present results indicate for the first time that changes in nucleotides may occur incnr1mRNA maturation and that this phenomenon might not be restricted to the frog.
The Creation of the Office for National Statistics
Authors: Pullinger John
Published: May 2007

A new Office for National Statistics was created in the United Kingdom in 1996 following a series of developments designed to strengthen the relevance and integrity of statistics. This paper describes these fundamental changes and sets out a blueprint for future progress. It also sets current developments in the United Kingdom in an historical and international context.
Multivariate Process Monitoring Using the Dynamic Biplot
Authors: Sparks Ross , Adolphson Allan , Phatak Aloke
Published: May 2007

In this article, we present a method for monitoring multivariate process data based on the Gabriel biplot. In contrast to existing methods that are based on some form of dimension reduction, we use reduction to two dimensions for displaying the state of the process but all the data for determining whether it is in a state of statistical control. This approach allows us to detect changes in location, variation, and correlational structure accurately yet display a large amount of information concisely. We illustrate the use of the biplot on an example of industrial data and also discuss some of the issues related to a practical implementation of the method.
Concepts Used in Statistical Business Registers in View of Globalisation and the Information Society
Authors: Nielsen Peter Bøegh , Plovsing Jan
Published: May 2007

The globalisation of markets and the development of the information society are two factors increasingly affecting statistical business registers. The article describes a number of problems caused by the globalisation process and the information society as which kind of business units should be recorded‐enterprises or enterprise groups, how cross‐border ownership, control and cooperation could be identified in the administrative registers, classification of activity in connection with foreign subsidiaries, recording of date of commencement of foreign subsidiaries in a national economy, recording of places of work in the case of teleworking, problems in connection with the recording of individuals involved in teleworking as self‐employed persons and the emergence of virtual enterprises. The article also raises the question of whether there is a need for an international satellite register for (transnational) concerns. Both globalisation and the growing information society therefore place new demands on statistical business registers, and these demands might necessitate mobilisation of additional resources for maintaining and developing the registers.
Bayesian Enhancement of Speech and Audio Signals which can be Modelled as ARMA Processes
Authors: Godsill Simon J.
Published: May 2007

In application areas which involve digitised speech and audio signals, such as coding, digital remastering of old recordings and recognition of speech, it is often desirable to reduce the effects of noise with the aim of enhancing intelligibility and perceived sound quality. We consider the case where noise sources contain non‐Gaussian, impulsive elements superimposed upon a continuous Gaussian background. Such a situation arises in areas such as communications channels, telephony and gramophone recordings where impulsive effects might be caused by electromagnetic interference (lightning strikes), electrical switching noise or defects in recording media, while electrical circuit noise or the combined effect of many distant atmospheric events lead to a continuous Gaussian component.

In this paper we discuss the background to this type of noise degradation and describe briefly some existing statistical techniques for noise reduction. We propose new methods for enhancement based upon Markov chain Monte Carlo (MCMC) simulation. Signals are modelled as autoregressive moving‐average (ARMA); while noise sources are treated as discrete and continuous mixtures of Gaussian distributions. Results are presented for both real and artificially corrupted data sequences, illustrating the potential of the new methods.
A Review of Nonparametric Time Series Analysis
Authors: Härdle Wolfgang , Lütkepohl Helmut , Chen Rong
Published: May 2007

Various features of a given time series may be analyzed by nonparametric techniques. Generally the characteristic of interest is allowed to have a general form which is approximated increasingly precisely when the sample size goes to infinity. We review nonparametric methods of this type for estimating the spectral density, the conditional mean, higher order conditional moments or conditional densities. Moreover, density estimation with correlated data, bootstrap methods for time series and nonparametric trend analysis are described.
The Language of Chance
Authors: Bellhouse D.R. , Franklin J.
Published: May 2007

Prior to 1654, the accepted date of the birth of the probability calculus, the publication of probabilistic calculations was very spotty. The few calculations that have been made are reviewed in David (1962), Coumet (1965), Hald (1990), Kendall (1956), Schneider (1988), and Todhunter (1865). In view of the paucity of the publication record, authors such as Hacking (1975) have argued that modern concepts of probability did not exist before 1654. Other authors have speculated about what held up the development of the probability calculus.

We examine the use and context of what in modern usage are now considered to be probabilistic words. These are words such as lots, chance and odds like twenty to one. The examination of the English literature leads one to believe that knowledge of an elementary probability calculus was present in the culture well before 1654. Simple probabilities were calculated probably as early as the time of Chaucer (1340?–1400). Subjective probability statements through the quotation of odds and through the description of fair and false dice were well understood by mid‐sixteenth century.
Effet des Evolutions Techniques et des Changements de la Spécialisation Internationale sur les Marchés du Travail et les Systèmes Productifs: Comment les Statisticiens Pourraient‐ils Relever les Défis?
Authors: Malinvaud Edmond
Published: May 2007

Thinking about future needs and about what can reasonably be expected as feasible in the next century, how should producers of statistics direct their activity? Increasing complexity and diversity of needs leads us to recognize that, between producers and users of statistics, a mediating role is more and more often played by analysts and research workers who are requesting above all good data bases. Concerning infrastructures for statistics on productive systems, coordination between accountants and statisticians will be crucial, as well as adaptation of the constraints which, because of excessive worry about confidentiality, could prevent establishment or use of data bases. In an increasingly competitive world, where private firms will sell analyses and informations, particularly on very large enterprises, the public statistical service will remain essential in all respects. Intangible investments, innovations and many aspects of the internal organization of firms will create formidable challenges. Information on employment and labour markets has been much developed during the past decades; but on a few specific and difficult issues progress is still needed: lifecyles in the working‐age population, acquisition of knowledge and skills in formal education and on the job, matching labour supplies and demands, and so on. Particular attention will have to be given to the lower levels of cultural and professional skills.
New Pedagogy and New Content: The Case of Statistics
Authors: Moore David S.
Published: May 2007

Statistical education now takes place in a new social context. It is influenced by a movement to reform the teaching of the mathematical sciences in general. At the same time, the changing nature of our discipline demands revised content for introductory instruction, and technology strongly influences both what we teach and how we teach. The case for substantial change in statistics instruction is built on strong synergies between content, pedagogy, and technology. Statisticians who teach beginners should become more familiar with research on teaching and learning and with changes in educational technology. The spirit of contemporary introductions to statistics should be very different from the traditional emphasis on lectures and on probability and inference.
Administrative Records and Surveys as Basis for Statistics on International Labour Migration
Authors: Hoffmann Eivind
Published: May 2007

This paper discusses possible sources for statistics to be used for describing and analysing the number, structure, situation, development and impact of migrant workers. The discussion is focused on key, intrinsic features of the different sources, important for the understanding of their strengths and weaknesses, and draws the reader's attention to features which may tend to undermine the quality of the statistics produced as well as ways in which the impact of such features can be evaluated and, if possible, reduced. This discussion thereby provides concrete illustrations of many of the methodological issues referred to in (Hoffmann, 1995).

The paper is organized around three key groups of migrant workers:

Persons who are arriving in a country to work there, i.e. the inflow of foreign workers;

Persons who are leaving their country to find work abroad, i.e. the outllow of migrant workers

Stock of foreign workers in the country.

Definitions of these groups are given in section 2. Sections 3 to 5 review, for each key group, main possible sources of statistics and the extent to which they can cover the group and identify separately important sub‐groups. The discussion in each section distinguishes between administrative registrations and statistical surveys, and deals with the capacity of a source to provide estimates of the size of the group, and whether it can provide estimates of the amount of change in the group over time, or at least indications of the direction of such changes. Section 6 outlines problems related to other data quality dimensions, such as frequency and timeliness of the statistics as well as the validity, reliability and consistency of the registration of variables used to describe migrant workers and where they come from. Section 7 presents strategies for the development of statistics on migrant workers based on two model scenarios for “countries” of different geographic circumstances and institutional capacities. Summary recommendations on how to organize cooperation, for the production of statistics on migrant workers, between the relevant agencies and between them and the potential users are proposed in the concluding section. The overall conclusion is that trying to piece together a coherent statistical picture of any of the above key groups is similar to trying to put together a large puzzle based on photographs of a rapidly changing reality, with important pieces missing and many of the available photographs out of focus.
I.J. Bienaymé [1796–1878]: Criticality, Inequality, and Internationalization*
Authors: Seneta E.
Published: May 2007

Two striking contributions of Bienaymé to mathematical statistics: (1) a completely correct statemet of the Criticality Theorem for simple branching processes in 1845; and (2) the derivation of the Bienaymé‐Chebyshev Inequality, are revisited on the 200th anniversary of his birth. We use writings and archival materials available since the note of Heyde & Seneta (1972) to present a fuller biographical picture. Bienaymé's connections with Buniakovsky and Chebyshev are elucidated, and this role in furthering Chebyshev's international contacts outlined. A concluding section illuminates Bienaymé's understanding of the linear regression of one random variable on another in an actuarial context of random shocks.
Estimation in Surveys Using Conditional Inclusion Probabilities: Simple Random Sampling
Authors: Tillé Yves
Published: May 2007

In survey sampling, auxiliary information on the population is often available. The aim of this paper is to develop a method which allows one to take into account such auxiliary information at the estimation stage by means of conditional bias adjustment. The basic idea is to attempt to construct a conditionally unbiased estimator. Four estimators that have a small conditional bias with respect to a statistic are proposed. It is shown that many of the estimators used in the literature in the case of simple random sampling can be obtained by using this estimation principle. The problem of simple random sampling with replacement, poststratification, and adjustment of a 2 x 2 dimensional contingency table to marginal totals are discussed in the conditional framework. Finally it is shown that the regression estimator can be viewed as an approximation of an application of the conditional principle.
Random Sets: Models and Statistics
Authors: Stoyan Dietrich
Published: May 2007

This paper surveys aspects of the theory of random closed sets, focussing on issues of practical and current interest. First, some historical remarks on this part of probability theory are made, where the important role of Georges Matheron is emphasized. Then, fundamental characteristics of the distribution of random closed sets are introduced. The very important Boolean model serves as an example for discussing mathematical and statistical problems. A number of further models is then considered, namely excursion sets of random fields, the system of edges of the Poisson Voronoi tessellation and various random systems of non‐overlapping spheres. Finally, some ideas of particle statistics are presented, including some models of random compact sets.
Inferring Gene Ancestry: Estimating Gene Descent
Authors: Thompson Elizabeth
Published: May 2007

Segregation indicators provide a fundamental description of the outcomes of Mendelian segregation. This description facilitates algorithms for computation of probabilities of gene identity patterns among individuals in a specified genealogical structure. Such gene identity patterns determine in turn the pattern of observable trait similarities among relatives. Conversely, patterns of gene identity are the parameters of genealogical relationship that can be estimated from trait data on individuals. Where data on large numbers of individuals or at large numbers of genetic loci are to be analyzed, Markov chain Monte Carlo realizations of underlying Mendelian segregation indicators can be used to provide Monte Carlo estimates of likelihoods for gene ancestry or of genetic model parameters. Genealogical information in genetic data is bounded by the information in patterns of genomic identity by descent. A different form of Monte Carlo likelihood can be used to assess this information.
Statistical Analysis of Product Warranty Data*
Authors: Lawless J.F.
Published: May 2007

Data bases regarding warranty claims for manufactured products record claims experience and information about concomitant factors. If constructed and maintained properly, warranty data bases may be used for a variety of purposes that include the prediction of future claims, the comparison of claims experience for different groups of products, the estimation of field reliability, and the identification of opportunities for quality and reliability improvement. This paper reviews some methods of analyzing warranty data and of addressing these objectives. Some extensions of previous work and suggestions for future development are included. Examples involving warranty claims for automobiles and regrigerators are considered.
A Comment on The Creation of the Office for National Statistics by John Pullinger
Authors: Puig Antonio
Published: May 2007

This article establishes the availability of statistical information in Mexico. A good statistical information system is a necessary, not a sufficient condition for economic and social development.
Three Sides of Smoothing: Categorical Data Smoothing, Nonparametric Regression, and Density Estimation
Authors: Simonoff Jeffrey S.
Published: May 2007

The past forty years have seen a great deal of research into the construction and properties of nonparametric estimates of smooth functions. This research has focused primarily on two sides of the smoothing problem: nonparametric regression and density estimation. Theoretical results for these two situations are similar, and multivariate density estimation was an early justification for the Nadaraya‐Watson kernel regression estimator.

A third, less well‐explored, strand of applications of smoothing is to the estimation of probabilities in categorical data. In this paper the position of categorical data smoothing as a bridge between nonparametric regression and density estimation is explored. Nonparametric regression provides a paradigm for the construction of effective categorical smoothing estimates, and use of an appropriate likelihood function yields cell probability estimates with many desirable properties. Such estimates can be used to construct regression estimates when one or more of the categorical variables are viewed as response variables. They also lead naturally to the construction of well‐behaved density estimates using local or penalized likelihood estimation, which can then be used in a regression context. Several real data sets are used to illustrate these points.
Imputation: Methods, Simulation Experiments and Practical Examples
Authors: Nordholt Eric Schulte
Published: May 2007

When conducting surveys, two kinds of nonresponse may cause incomplete data files: unit nonresponse (complete nonresponse) and item nonresponse (partial nonresponse). The selectivity of the unit nonresponse is often corrected for. Various imputation techniques can be used for the missing values because of item nonresponse. Several of these imputation techniques are discussed in this report. One is the hot deck imputation. This paper describes two simulation experiments of the hot deck method. In the first study, data are randomly generated, and various percentages of missing values are then non‐randomly‘added’to the data. The hot deck method is used to reconstruct the data in this Monte Carlo experiment. The performance of the method is evaluated for the means, standard deviations, and correlation coefficients and compared with the available case method. In the second study, the quality of an imputation method is studied by running a simulation experiment. A selection of the data of the Dutch Housing Demand Survey is perturbed by leaving out specific values on a variable. Again hot deck imputations are used to reconstruct the data. The imputations are then compared with the true values. In both experiments the conclusion is that the hot deck method generally performs better than the available case method. This paper also deals with the questions which variables should be imputed and what the duration of the imputation process is. Finally the theory is illustrated by the imputation approaches of the Dutch Housing Demand Survey, the European Community Household Panel Survey (ECHP) and the new Dutch Structure of Earnings Survey (SES). These examples illustrate the levels of missing data that can be experienced in such surveys and the practical problems associated with choosing an appropriate imputation strategy for key items from each survey.
On the Application of Conditional Independence to Ordinal Data
Authors: Wermuth Nanny , Cox D.R.
Published: May 2007

A special log linear parameterization is described for contingency tables which exploits prior knowledge that an ordinal scale of the variables is involved. It is helpful, in particular, in guiding the possible merging of adjacent levels of variables and may simplify interpretation if higher‐order interactions are present. Several sets of data are discussed to illustrate the types of interpretation that can be achieved. The simple structure of the maximum likelihood estimates is derived by use of Lagrange multipliers.
Combining Data from Surveys and Administrative Record Systems. The Norwegian Experience
Authors: Thomsen Ib , Holmøy Ann Marit Kleive
Published: May 2007

At Statistics Norway administrative data have been extensively used in order to improve the quality of survey data. Various techniques have been used to reduce sampling variance and/or to reduce the effects of non‐response. In the present article some of the most commonly used methods are being presented, and based on empirical rather than theoretical evaluations, we give our conclusions concerning their potentials and limitations.
Assessment and Statistics Education: Current Challenges and Directions
Authors: Garfield Joan B. , Gal Iddo
Published: May 2007

The interaction between new curricular goals for students and alternative methods of assessing student learning is described. Suggestions are offered for teachers of statistics who wish to re‐examine their classroom assessment practices in light of these changes. Examples are offered of some innovative assessment approaches that have been used in introductory statistics courses, and current challenges to statistics educators are described.
Evolution of Statistics in India
Authors: Ghosh J.K. , Maiti P. , Rao T.J. , Sinha B.K.
Published: May 2007

This is a brief history of the evolution of official and academic Statistics in India which focuses mainly on the period 1930 to 1960 but traces its origins in antiquity and recent history. We also comment on how Statistics has continued to evolve since the 1960's. This is a history of both institutions and people, who built and shaped them, and of ideas.
Are We Measuring Up …? Questions on the Performance of National Statistical Systems
Authors: de Vries Willem
Published: May 2007

This article proposes a systematic approach to evaluating the performance of national statistical systems. Its starting point are the so‐called Fundamental Principles of Official Statistics, which were adopted by the United Nations some time ago. The aim is to translate the principles into operational terms and concrete questions about ‘how we are measuring up’.
Using Statistics and Statistical Thinking to Improve Organisational Performance
Authors: Dransfield S. B. , Fisher N. I. , Vogel N. J.
Published: May 2007

A systematic approach to measuring organisational performance is fundamental to the pursuit of business excellence. As such, the area of organisational performance measurement, and its use of data and analysis to inform business decisions, affords statisticians a potentially high value‐adding opportunity. To be effective in this area, statisticians need to appreciate the differing requirements for statistical information in various management zones of an enterprise.

This paper describes a strategy that seeks to link measurement to all facets of organisational performance, particularly to desired business outcomes, and also to mesh measurement with process improvement in a natural way. The use of statistics and statistical thinking is then discussed in this context, with particular focus on the opportunity for statisticians to have a key role at the top decision‐making level of the organisation. We argue that the role requires skills in both advanced technical statistical modelling and analysis, and in statistical thinking. It also requires a preparedness to form an appreciation of the business and management imperatives faced by the leaders of an enterprise, and a willingness to work from this basis.
Developing a Census Data System in China
Authors: Shen Jianfa , Chu David , Zhang Qingpu , Zhang Weimin
Published: May 2007

China has conducted four population censuses since 1949. A large amount of important information about population, education, employment, migration and urbanization was collected in the most recent 1990 census. This paper will examine main features and key issues of the Chinese population census and the census data. Some fundamental considerations in building a computerized census data system and concerning the ways in which a system might be developed will be discussed. Themain objective and features of the on‐going Population GIS of China project will also be examined.
Determinacy in the Linear Model: Gauss to Bose and Koopmans
Authors: Aldrich John
Published: May 2007

Gauss showed that least squares fails to produce a unique solution only when the problem is indeterminate. This note considers his argument and the notion of indeterminacy underlying it. It also relates the argument to twentieth‐century discussions of estimability and identifiability.
Methods for Default and Robust Bayesian Model Comparison: the Fractional Bayes Factor Approach
Authors: De Santis Fulvio , Spezzaferri Fulvio
Published: May 2007

In the Bayesian approach to model selection and hypothesis testing, the Bayes factor plays a central role. However, the Bayes factor is very sensitive to prior distributions of parameters. This is a problem especially in the presence of weak prior information on the parameters of the models. The most radical consequence of this fact is that the Bayes factor is undetermined when improper priors are used. Nonetheless, extending the non‐informative approach of Bayesian analysis to model selection/testing procedures is important both from a theoretical and an applied viewpoint. The need to develop automatic and robust methods for model comparison has led to the introduction of several alternative Bayes factors. In this paper we review one of these methods: the fractional Bayes factor (O'Hagan, 1995). We discuss general properties of the method, such as consistency and coherence. Furthermore, in addition to the original, essentially asymptotic justifications of the fractional Bayes factor, we provide further finite‐sample motivations for its use. Connections and comparisons to other automatic methods are discussed and several issues of robustness with respect to priors and data are considered. Finally, we focus on some open problems in the fractional Bayes factor approach, and outline some possible answers and directions for future research.
Bayes Convolution
Authors: van den Heuvel Edwin R. , Klaassen Chris A. J.
Published: May 2007

A general convolution theorem within a Bayesian framework is presented. Consider estimation of the Euclidean parameter θ by an estimator T within a parametric model. Let W be a prior distribution for θ and define G as the W‐average of the distribution of T ‐ θ under θ. In some cases, for any estimator T the distribution G can be written as a convolution G = K * L with K a distribution depending only on the model, i.e. on W and the distributions under θ of the observations. In such a Bayes convolution result optimal estimators exist, satisfying G = K. For location models we show that finite sample Bayes convolution results hold in the normal, loggamma and exponential case. Under regularity conditions we prove that normal and loggamma are the only smooth location cases. We also discuss relations with classical convolution theorems.
Estimating Capital Inputs for Productivity Measurement: An Overview of U.S. Concepts and Methods
Authors: Harper Michael J.
Published: May 2007

The U.S. Bureau of Labor Statistics (BLS) publishes measures of multifactor productivity, which are patterned after the Solow residual. Inputs of capital must be aggregated with inputs of labor. The theory requires a measure of the capital service flow, a rather abstract notion which is rarely observable. The BLS procedures for capital measurement are summarized, and the rationale for these procedures is explored. Implicit measures of capital services are derived from data on property income and data on historical investments which are detailed as to type of asset.
Indicators, Green Accounting and Environment Statistics— Information Requirements for Sustainable Development
Authors: Radermacher Walter
Published: May 2007

Since the “Earth Summit” in Rio de Janeiro 1992 the term “sustainable development” determines the third and current phase of environmental policy. A precise and commonly accepted definition of sustainable development (s.d.) is still missing. There are, nevertheless, some elements in the philosophy of sustainable development which–even if they are still vague–could be used as guidelines for a framework of “green” accounting and sustainability indicators. Based on theoretical considerations, the German Federal Statistical Office has developed a framework for an Environmental Economic Accounting System. The objective is to add meaningful modules to the traditional System of National Accounts which are designed to quantify the external (environmental) effects of economic activities. The framework could already be realised and published to an extent that is relevant for actual policy making in Germany.
The Early History of the Cumulants and the Gram‐Charlier Series
Authors: Hald Anders
Published: May 2007

The early history of the Gram‐Charlier series is discussed from three points of view: (1) a generalization of Laplace's central limit theorem, (2) a least squares approximation to a continuous function by means of Chebyshev‐Hermite polynomials, (3) a generalization of Gauss's normal distribution to a system of skew distributions. Thiele defined the cumulants in terms of the moments, first by a recursion formula and later by an expansion of the logarithm of the moment generating function. He devised a differential operator which adjusts any cumulant to a desired value. His little known 1899 paper in Danish on the properties of the cumulants is translated into English in the Appendix.
Sick‐leave and Other Job‐related Health Issues from Labour Force Surveys Data
Authors: Campostrini Stefano , Bellini Pierantonio
Published: May 2007

Most research into the relationship between health and work has been limited to ad hoc studies: few studies have been based on large‐sample surveys directed to the general population. We propose here approaches to developing work‐related health indicators from currently collected National Labour Force Surveys, in particular the Italian Labour Force Survey‐ISTAT. Four potential indicators are proposed: temporary reduction in working ability (TRWA), continued reduction in working ability (CRWA), permanent inability to work (PIW), and exclusion from the active population (EAP). Our analysis indicates that CRWA and EAP are highest among manual workers, consistent with the well‐described relationship between job class and health status. This approach provides an opportunity to monitor the relative health status of workers on a continuing basis using readily available, population‐based data and to conduct additional analyses on the basis of occupational stratification.
Australian Commonwealth Government Statistical Clearing House: Vehicle for Reducing Response Load and Improving Survey Quality
Authors: Colledge Michael J. , Starick Rosslyn
Published: May 2007

The recently constituted Commonwealth Government Statistical Clearing House was set up in response to a small business task force recommendation. It is operated by the Australian Bureau of Statistics (ABS) as part of that agency's coordination role. Its primary goal is to ensure that surveys impose minimum load on business respondents and that the data collected are fit for their intended uses. Surveys affecting 50 or more businesses conducted by or on behalf of Australian Government departments or agencies, including the ABS itself, are subject to a clearance process. Those that are not approved are not permitted to start or continue. Statistical Clearing House review procedures not only aim to reduce respondent load and promote good design, they also ensure good documentation and facilitate data sharing. Metadata descriptions of all the surveys subject to review are recorded in the Commonwealth Register of Surveys of Businesses, publicly accessible via the Internet.

This paper augments and updates previously published material. It outlines the objectives, development and operation of the Statistical Clearing House from the perspective of its contribution to reduction in respondent load and improvement in survey quality. It describes the review criteria and the survey metadata that are required to support the clearance process. It briefly compares and contrasts similar programs at other statistical agencies. Finally, it summarises the first year of operations. The tentative conclusion is that the benefits brought by the program in terms of increased survey taker awareness of respondent load and quality issues outweigh the additional work required by survey managers to comply with the program and the costs of administering it.
Realistic Statistical Modelling of Financial Data
Authors: Rydberg Tina Hviid
Published: May 2007

The aim of this paper is to present some of the stylized features of financial data which have received a lot of attention both from practitioners and those with more theoretical backgrounds. Some of the models resulting from these efforts are reviewed and discussed. To facilitate the discussion two data sets are used: one of these contains all US trades in IBM stocks in 1995 at NYSE.
Microsimulation of Business Performance
Authors: Kokic Philip , Chambers Ray , Beare Steve
Published: May 2007

Microsimulation of business performance based on sample survey data is a relatively underdeveloped field, but its application in government economic policy formulation is potentially great since it can be used to measure the distributional effects of change rather than just average change. Techniques which account for the dynamic response of businesses to macro level price expectations have recently been developed (Kokic et al., 1993). These allow individual level business performance to be forecast from sample survey data. In this paper we outline a general methodology for combining these forecasting techniques with Monte Carlo simulation in order to produce a microsimulation of business performance that accurately captures the true distributional characteristics of the underling survey data. Applying this methodology to Australian farm survey data, we show that these methods may be used to forecast the distribution of farm business production and performance within arbitrary subdomains of the surveyed population conditional on a given set of expected commodity price outcomes. The microsimulations reflect both the uncertainty due to climatic variation from one year to the next, which in the Australian context depends largely on geographic location, as well as the uncertainty of commodity prices.
Ten More Years of Error Rate Research
Authors: Schiavo Rosa A. , Hand David J.
Published: May 2007

The assessment of the performance of supervised classification rules by estimating their error rate (the proportion of objects misclassified) is an important area of work in statistical pattern recognition. This paper reviews the last ten years of error rate research, bringing up to date the reviews of Hand (1986a) and McLachlan (1987). Since those surveys were published, old estimators have been improved new estimators have been introduced, and new approaches to error rate estimation have been developed. Some of this work has led to deep insights into classification methodology and statistical modelling in general.
Designs for Variance Components Estimation: Past and Present
Authors: Khuri André I.
Published: May 2007

This article provides (1) a comprehensive coverage of the literature on designs for estimating variance components, and (2) a review of recent applications of such designs in genetics, statistical process control, and quality improvement. In addition, recent methods of estimation of variance components and model forms, other than the linear, are discussed. The latter developments have a direct effect on the choice of design. Some suggested ideas for future research directions are also given.
Generalized Symmetry Models for Hypercubic Concordance Tables
Authors: Lovison Gianfranco
Published: May 2007

Frequency data obtained classifying a sample of ‘units’ by the same categorical variable repeatedly over ‘components’, can be arranged in ahypercubic concordance table (h.c.t.). This kind of data naturally arises in a number of different areas such as longitudinal studies, studies using matched and clustered data, item‐response analysis, agreement analysis. In spite of the substantial diversity of the mechanisms that can generate them, data arranged in a h.c.t. can all be analyzed via models of symmetry and quasi‐symmetry, which exploit the special structure of the h.c.t. The paper extends the definition of such models to any dimension, introducing the class ofgeneralized symmetry models, which provides a unified framework for inference on categorical data that can be represented in a h.c.t., Within this framework it is possible to derive the common structure which underlies these models and clarify their meaning; their usefulness in applied work is illustrated by a re‐analysis of two real examples.