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This paper describes the lessons learnt from experience of programming survey analysis for the Rothamsted computer. The difficulties of handling large quantities of data, especially on small computers, are discussed and a general programme for the analysis of surveys is described.

The paper reviews some of the statistical problems arising in the design and analysis of long-term cyclic experiments comparing different crop rotations. Three types of design are distinguished and their properties considered. These are basic designs with all phases of the rotations in each block, reduced designs with mutually exclusive groups of phases kept in separate blocks and phase-confounded designs in which some contrasts between test crops are partially confounded with block differences. Methods of analysing the yields of test crops by estimating the mean effects of the rotations over the years and regressions on seasonal and time variates are discussed theoretically for replicated experiments of basic or reduced design. The analysis is complicated by correlations between yield values recurring on the same plots and by lack of homogeneity in residual year-to-year variations in rotation effects. The main topics considered are (1) the estimation of errors, (2) the losses of information due to using unweighted means and regressions ignoring the correlations, (3) methods for recovering this information.

This paper describes an electronic computer program for the analysis of multivariate data. The program is interactive in the sense that its control structure is designed to facilitate a step‐by‐step process of analysis extending over several computer runs. Especially comprehensive input routines allow the user flexibility in data presentation. A group structure can be imposed and within‐ and between‐group analyses are possible. The program includes all the usual multivariate techniques, but special attention has been paid to providing a wide repertoire of operations useful in multiple‐regression analysis.

23 páginas, 13 figuras, 2 tablas., The present paper includes a morphological, ecological and biological updating of the three gorgonian associated species of Haplosyllis (Polychaeta, Syllidae) known to date: H. chamaeleon (symbiont with Paramuricea clavata in the Mediterranean), H. anthogorgicola (symbiont with Anthogorgia bocki in the Japanese seas) and H. villogorgicola , a new species living symbiotically with Villogorgia bebrycoides which is only known from Tenerife (Canary Islands, Eastern Central Atlantic). The new species is described on the basis of ecological, morphological, morphometric and statistical analysis of relevant characteristics. Each host colony harboured about 15 pale-yellowish worms, whose cryptic colouration mimicked that of the host. They occurred either on the host branches or partly hidden inside cavities formed by the fusion of two branches. The new species is characterized by the presence of simple chaetae with clearly bidentate tips all along the body, the presence of gland pore aggregates distributed in two lateral rows and two ventral patches on each palp and the absence of ciliary tufts on the pharyngeal papillae. H. villogorgicola sp. nov. is closely related to H. chamaeleon . Thus, it is compared with two populations of this species collected in the north-west and south-west Mediterranean. Stolons of H. chamaeleon are re-described as tetracerous and a peculiar posterior end regeneration process occurring in adult worms during the stolon formation is described. H. anthogorgicola is also re-described, with particular emphasis on its appendage and chaetal arrangements. The main features of the three associations are discussed in light of the current knowledge on symbiotic polychaetes, particularly cnidarian-associated syllids. © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 77 , 455–477., This paper is a contribution to the research project INTAS-97–0916.

This paper has two aims. The first is to exposit the various forms of the LM statistic and to collect together some of the relevant research reported in the mathematical statistics literature. The second is to illustrate the construction of LM tests by considering a number of particular econometric specifications as examples. It will be found that in many instances the LM statistic can be computed by a regression using the residuals of the fitted model which, because of its simplicity, is itself estimated by OLS. The paper contains five sections. In Section 2, the LM statistic is outlined and some alternative versions of it are discussed. Section 3 gives the derivation of the statistic for several econometric specifications. Applications in this section are the testing for a liquidity trap, autocorrelation, the error components model, diagonality of a covariance matrix in seemingly unrelated equation systems and choice between models generated by separate families of distributions. Section 4 considers the construction of a pseudo-LM statistic when estimation is difficult even under the null hypothesis and discusses the derivation of the exact distribution of the statistic. A concluding summary is given as Section

Freezing preservation of banana (Musa cavendishii, var. enana) was investigated. Microwave treatment of banana slices at 650 watts for 2 min or immersion of whole peeled fruits in boiling water for 11 min followed by freezing at -24°C inhibited color deterioration in the frozen product. Treatments showed different effectiveness depending on the enzymatic system studied [polyphenoloxidase (PPO) or peroxidase (POD)] and banana maturity level at the processing date. Blanching in boiling water yielded a good frozen product in which no darkening was observed. The proper stage of ripeness for processing of this banana cultivar was characterized by a firmness of 1.24 kg, a pulp/skin ratio of 1.30 and a green (70%)-yellow (30%) peel color.

Illustration of a methodological flow in the paper of the same name by Mosley, et al, and discusses the limitation of their approach.

Nonconvexities in the criterion function of adaptive control problems were first found about ten years ago with numerical methods. Recently they have been confirmed by B. Mizrach (1991) with analytical methods. He found that a source of the nonconvexity was the probing component of the cost-to-go. Mizrach's results have been extended in this paper. First, the probing function has been characterized and found to support the use of algorithms that exploit this character to find the global optimum. Secondly, a new source of nonconvexities has been found in the cautionary component of the cost-to-go. Copyright 1995 by Economics Department of the University of Pennsylvania and the Osaka University Institute of Social and Economic Research Association.

Direct or "command-and-control" regulation has had limited success in dealing with occupational health and safety and with environmental regulation. This lack of success has led policymakers to experiment with self-regulation as an alternative means of achieving the goals of social regulation. The economic subsystem fails to acknowledge its social identity and, therefore, appears to be blind to its negative performance regarding the environment and the workplace. The authors of this paper argue that moving beyond command-and-control can be feasible and desirable, at least to a certain extent, but that pitfalls are omnipresent. "Regulatory dilemmas" need to be solved, sound empirical studies need to be conducted, and a guiding theory needs to be drafted. To achieve these goals, the authors suggest use of the key concept of "reflexivity," which refers to the economic organization's relationship with itself. The practical usefulness of this theoretical concept is explored against the background of regulatory practice in the areas of occupational safety and health and the environment. It is concluded that a mode of reflexive administrative law requires a "negotiating government," which adopts a mixture of strategies and learns to cope with issues like third-party interests, access to information, and enforcement.

Personal pronouns have distributional properties which are in important respects different from those of full NPs. Pronominal objects of a preposition, personal pronoun subjects and objects have therefore been analysed as clitics. A clitic analysis has also been proposed for adverbs. In this paper I concentrate on the question of how we can recognise clitics. Some proposed criteria are tested on the Old English material, leading to the conclusion that there is some support for a clitic analysis, but that it cannot be concluded that personal pronouns are always clitics. It is likely that they behave sometimes like ordinary NPs. Adverbs are unlikely to be clitics.

The purpose of this paper is to consider how grammaticalisation, which is generally considered to be a diachronic process, can be fitted into a theory of language change that is based on the idea that change is brought about by the speaker, and hence is essentially a synchronic matter. First the question of the relation between explanation, the theory of grammar and the theory of change will be discussed, on the basis of which a number of guidelines will be suggested which should direct empirical research in the area of language change. In the second part of the paper, one particular case of grammaticalisation will be investigated, namely the development of have to in English from a possessive, full verb to a modal semi-auxiliary. It will be shown that this case contains both diachronic and synchronic aspects, which need to be kept apart. In keeping them apart, this particular case of grammaticalisation can be seen to accord with the principles of language change argued for in the first part.

El pdf del artículo es la versión post-print., This paper uses a CAD methodology proposed by the authors to design a low-power 2nd-order Sigma-Delta Modulator (ΣΔM). This modulator has been fabricated in a 0.7μm CMOS technology to be used as the front-end of an energy-metering mixed-signal ASIC and features 16.4 bit at a digital output rate of 9.6 kHz with a power consumption of 1.7 mW. It yields a value of Power(W)/[2^resolution(bit) * Outpur rate(Hz)] which is the smallest reported to now, thus demonstrating the possibility to design high-performance embeddable ΣΔMs using CAD methodologies.

This paper examines the extent to which real estate returns are driven by continental factors. This subject is relevant for determining the country allocation of international real estate portfolios. If returns are driven by a continental factor, investors should look for diversification opportunities outside their own continent. This paper finds strong continental factors in North America and especially in the United States. For the Asia–Pacific region, real estate returns are not driven by a continental factor. The results suggest that, for European, North American and Asia—Pacific real estate portfolio managers, the Asia—Pacific region provides attractive international diversification opportunities.

This paper studies the price dynamics induced by strategic firm behavior in the presence of consumer learning about the uncertain quality differential of the products offered by a duopoly. It is found that consumers learn slowly and that prices converge also slowly to full-information levels. A consequence is that the incentives of firms to manipulate consumers' beliefs are persistent. Although pricing tends to be aggressive at the early stages, and average prices eventually increase over time, price wars may occur at intermediate stages of the product life cycle., We thank the Spanish Ministry of Education for partial financial support through DGCYT grants PB95-0130 and PB93-0679.

El pdf del artículo es la versión de autor., This paper presents SIRENA, a CAD environment for the simulation and modelling of mixed-signal VLSI parallel processing chips based on cellular neural networks. SIRENA includes capabilities for: (a) the description of nominal and non-ideal operation of CNN analogue circuitry at the behavioural level; (b) performing realistic simulations of the transient evolution of physical CNNs including deviations due to second-order effects of the hardware; and, (c) evaluating sensitivity figures, and realize noise and Monte Carlo simulations in the time domain. These capabilities portray SIRENA as better suited for CNN chip development than algorithmic simulation packages (such as OpenSimulator, Sesame) or conventional neural networks simulators (RCS, GENESIS, SFINX), which are not oriented to the evaluation of hardware non-idealities. As compared to conventional electrical simulators (such as HSPICE or ELDO-FAS), SIRENA provides easier modelling of the hardware parasitics, a significant reduction in computation time, and similar accuracy levels. Consequently, iteration during the design procedure becomes possible, supporting decision making regarding design strategies and dimensioning. SIRENA has been developed using object-oriented programming techniques in C, and currently runs under the UNIX operating system and X-Windows framework. It employs a dedicated high-level hardware description language: DECEL, fitted to the description of non-idealities arising in CNN hardware. This language has been developed aiming generality, in the sense of making no restrictions on the network models that can be implemented. SIRENA is highly modular and composed of independent tools. This simplifies future expansions and improvements. Copyright © 1999 John Wiley & Sons, Ltd., This work has been partially funded by spanish CICYT under contract TIC96-1392-C02-02 (SIVA). Research of Ricardo Carmona has been partially supported by IBERDROLA, S. A. under contract INDES-94/377

Over the past few years, parties on the extreme right of the political spectrum have drawn a surprisingly large number of votes in elections throughout Western Europe, and surprisingly often. What these parties have in common is their aversion to ‘foreigners’, by which they mean anyone who hails from another country. This paper considers whether the presence of foreigners in the immediate surroundings of people's homes is a factor in their decision to cast their vote for any of these parties. It is based on an analysis of data on two elections held in Amsterdam in 1994. The analysis reveals that the presence of Moroccans and Turks, two population groups that are associated with an Islamic lifestyle, in the immediate surroundings of the home actually does increase the support for parties on the extreme right. In contrast, the presence of people from Surinam or the Antilles does not have that effect, while the presence of foreigners from other countries does not have that effect at all.

Instance-based reasoning systems and, in general, case-based reasoning systems are normally used in problems for which it is difficult to define rules. Although case-based reasoning methods have proved their ability to solve different types of problems, there is still a demand for methods that facilitate their automation during their creation and the retrieval and reuse stages of their reasoning circle. This paper presents one method based on kernels, which can be used to automate some of the reasoning steps of instance-based reasoning systems. Kernels were originally derived in the context of support vector machines, which identify the smallest number of data points necessary to solve a particular problem (e.g., regression or classification). Unsupervised kernel methods have been used successfully to identify the optimal instances to instantiate an instance base. The efficiency of the kernel model is shown on an oceanographic problem. © 2001 John Wiley & Sons, Inc.

This paper examines the relative degrees of risk sharing provided by demand deposit contracts and equity contracts. It is shown that in a framework in which individuals have smooth preferences and there exists some type of aggregate uncertainty (interest rate risk), the allocations obtained with a financial intermediary allow in general for greater risk sharing than those achieved in an equity economy. However, the interest rate is essential in order to determine the superiority of demand deposit contracts over equity contracts. The results of the paper contradict the ones obtained by Jacklin [1987] and Hellwig [1994], where demand deposit and equity contracts are always equivalent risk sharing instruments. Publicado

Efficient implementation of closed-loop supply chains requires setting up appropriate logistics structures for the arising flows of used and recovered products. In this paper we consider logistics network design in a reverse logistics context. We present a generic facility location model and discuss differences with traditional logistics settings. Moreover, we use our model to analyze the impact of product return flows on logistics networks. We show that the influence of product recovery is very much context dependent. While product recovery may efficiently be integrated in existing logistics structures in many cases, other examples require a more comprehensive approach redesigning a company's logistics network in an integral way

Given the evidence provided by Longstaff (1995), and Peña, Rubio and Serna (1999) a serious candidate to explain the pronounced pattern of volatility estimates across exercise prices might be related to liquidity costs. Using all calls and puts transacted between 16:00 and 16:45 on the Spanish IBEX‐35 index futures from January 1994 to October 1998 we extend previous papers to study the influence of liquidity costs, as proxied by the relative bid‐ask spread, on the pricing of options. Surprisingly, alternative parametric option pricing models incorporating the bid‐ask spread seem to perform poorly relative to Black‐Scholes. Publicado

On August 17, 1998, Russia defaulted on its domestic public debt, declared a moratorium on the private banks foreign liabilities which was equivalent to an outright default, and abandoned its exchange rate regime. The depth of the Russian meltdown shocked the international markets, and precipitated a period of serious financial instability. It is important to understand the roots of such a crisis to learn about possible lessons on both issues of bank supervision and international stability. While the visible cause of the crisis was an unsustainable fiscal deficit coupled with massive capital flight, the critical question concerns the origin of such circumstances. This paper argues that the structure of individual incentives in the Russian legal context, compounded by the exceptional support granted by international institutions to Russia, explains the cycle of nonpayment, capital flight and fiscal unbalances leading to the dramatic 1998 crisis. We offer an interpretative model of noncompliance, cash-stripping and rational collective nonpayment which led to the fiscal and banking crisis and ultimately to a complete meltdown. In our view, the banking sector was already insolvent prior to the crisis, and contributed directly and indirectly to it. The last section of the paper puts forward a radical medium-term policy proposal for a stable banking and payment system for Russia. Russia needs to create a basic foundation for savings and intermediation by asset restrictions and market segmentation, crude but effective rules used in all underdeveloped systems to restrain asset stripping and opportunism. Concretely, we propose a cautious extension of deposit insurance away from the monopolistic Sberbank and towards a narrow banking layer. The proposal also proposes measures to restore charter value in the commercial banking sector.

Discoid lupus erythematosus (DLE) is an uncommon disease in childhood. In this paper we present five new cases of childhood DLE. Two of them are identical twin brothers, who developed similar lesions during an interval of 5 years. This is in favour of the hypothesis that both genetic factors and somatic mutations, due to environmental factors, are implicated in the pathogenesis. A review of the English language literature is also presented. In order to have better epidemiological data on this disease, all cases of childhood DLE, including those published in non-English literature and those not yet published, should be placed together and analysed.

This paper considers a class of models in which rank-based payoffs are sensitive to small amounts of noise in decision making. Examples include auction, price-competition, coordination, and location games. Observed laboratory behavior in these games is often responsive to asymmetric costs associated with deviations from the Nash equilibrium. These payoff asymmetry effects are incorporated in an approach that introduces noisy behavior via probabilistic choice. In equilibrium, behavior is characterized by a probability distribution that satisfies a "rational expectations" consistency condition: the beliefs that determine player's expected payoffs match the decision distributions that arise from applying a logit probabilistic choice function to those expected payoffs. We prove existence of a unique, symmetric logit (quantal response) equilibrium and derive comparative statics results. The paper provides a unified perspective on many recent laboratory studies of games in which Nash equilibrium predictions are inconsistent with both intuition and experimental evidence.

This paper examines the spatial transformation of the city from children’s point of view. Three important daily living domains – children’s outdoor play spaces, leisure centres and caring institutions – are examined. Empirical findings are made from studies in Amsterdam, where new urban developments affecting children are most apparent in the Netherlands. Conclusions show that developments are both diverse and paradoxical. On the one hand, we see processes that progressively contribute towards the exclusion of children from urban public space. Safety considerations underpin these processes heavily. Children’s marginal position in the public domain is further reinforced in the planning and design of new residential areas. Children do not seem to be a factor that merits consideration. On the other hand, never before has so much attention been paid to children. Adults’ efforts to give due consideration to children’s position lead to the creation of many new domains especially created for children. These give children a ‘face’ in the city, but these spaces are characterised by privatisation, institutionalisation and segregation. In the context of the Netherlands it is not altogether clear what shape the future will take, but it seems to be most likely that indicated developments will continue.

7 pages, 8 figures, 1 table.-- Printed version published Apr 2003., Black liquors from a soda pulping mill were treated with the white-rot fungus Trametes versicolor to detoxify and reduce colour, aromatic compounds and chemical oxygen demand (COD). The fungus was used in the form of pellets in aerated reactors (fluidized, stirred and air-pulsed reactors). Reductions in colour and aromatic compounds of 70-80% and in COD of 60% were achieved. During the different experiments, laccase activity was detected but neither lignin peroxidase (LiP) nor manganese peroxidase activities were detected, although T versicolor is able to produce these enzymes. Experiments also showed a LiP activity inhibitory effect produced by lignin. From the results obtained, it can be concluded that there is a relationship between laccase production and toxicity reduction. This correlation responds to the equation Laccase production = 1.57 LN (toxicity reduction) -16.40. Copyright © 2003 Society of Chemical Industry, Financial support from CICYT in the framework of Project AMB 94-0287 and CIRIT through the Unitat d'Enginyeria Bioquímica of the Centre de Referència en Biotecnología (Generalitat de Catalunya).

16 páginas, 12 figuras.-- El documento se encuentra en su versión post-print., This paper analyses a 50 year time series of daily precipitation in a region of the middle Ebro valley (northeastern Spain) in order to predict extreme dry-spell risk. A comparison of observed and estimated maximum dry spells (50 year return period) showed that the generalized Pareto (GP) distribution combined with partial duration series (PDS) gives better results than the Gumbel distribution fitted to annual maximum series. Indeed, the classical Gumbel approach underestimated the empirical duration of dry spells. The PDS–GP approach was successfully applied in the study of extreme hydro-climatic variable values. The results reported here could be applied in estimating climatic drought risks in other geographical areas., This paper was supported by the following projects: ‘La sequía en Aragón: tendencias climáticas seculares y patrones de cambio ambiental’ (CLI99-098), ‘Caracterización espacio-temporal de las sequías en el valle medio del Ebro e identificación de sus impactos’ (BSO2002-02743), ‘Identificación de ´areas fuente de sedimento y áreas generadoras de escorrentía en relación con los cambios de uso del suelo’ (HIDROESCALA, REN2000-1709-C04-01/GLO) and ‘Procesos hidrológicos en áreas seminaturales mediterráneas’ (PROHISEM, REN 2001-2268-C02-01/HID), financed by the CICYT.

Research in the area of spatial decision support (SDS) and resource allocation has recently generated increased attention for integrating optimization techniques with GIS. In this paper we address the use of spatial optimization techniques for solving multi-site land-use allocation (MLUA) problems, where MLUA refers to the optimal allocation of multiple sites of different land uses to an area. We solve an MLUA problem using four different integer programs (IP), of which three are linear integer programs. The IPs are formulated for a raster-based GIS environment and are designed to minimize development costs and to maximize compactness of the allocated land use. The preference for either minimizing costs or maximizing compactness has been made operational by including a weighting factor. The IPs are evaluated on their speed and their efficacy for handling large databases. All four IPs yielded the optimal solution within a reasonable amount of time, for an area of 8 × 8 cells. The fastest model was successfully applied to a case study involving an area of 30 × 30 cells. The case study demonstrates the practical use of linear IPs for spatial decision support issues.

This paper presents a narrative review of recent research into applicant and recruiter reactions to new technology in employee selection. Different aspects of the use of new technology are noted including computer-based testing, Internet-based recruitment and candidate assessment, telephone-based and video-based interviews, video-based situational judgment tests, and virtual reality scenarios. It is argued that an appropriate way to conceptualize these advances is as ‘technical innovations’ as defined in the creativity and innovation research in Industrial, Work, and Organizational (IWO) psychology. Applicant reactions research is reviewed thematically, and studies into three main themes are discussed: Applicant preferences and reactions, equivalence, and adverse impact. Following Bartram (2001), an amphibian-monarchistic analogy is employed at several stages in the review. Four major criticisms of the extant applicant reactions research base are noted: its atheoretical orientation, a short-termist concentration upon reactions level outcomes, an over-reliance on students as surrogates, and a patchiness of coverage of crucial research questions. The second part of this paper explores neglected issues of recruiter adoption of new technology for employee selection. Again drawing from advances in the innovation and creativity literatures, this section explores likely antecedent factors at the individual and organizational levels of analysis. A general model of recruiter adoption of new technology is posited as a framework for future research in this area. For both applicant and recruiter reactions further research is called for and implications for practice are noted throughout.

This paper introduces and discusses a new polarization filter which can aid interpretation of single or multichannel multicomponent seismograms. We define a measure of degree of polarization based on instantaneous polarization attributes of analytic traces. Computation of the data eigenstructure is not required and the measure can be used in combination with its spatial coherence to enhance polarized signals on seismic record sections. Our approach avoids suppressing signals with spatially changing characteristics such as happens in the transition to post-critical reflections or for reflections from laterally varying interfaces. The simplicity of the method permits the filter to be tailored to various data characteristics and the concept can be applied to cross-energy methods. We also show that non-linear amplification of rectilinearity and planarity weight functions in time-domain principal-component filters permits the size of data windows to be decreased, improving resolution and suppressing noise., This research has been supported by the Spanish Ministry of Education, Culture, and Sport through grant SB2000-0120 and by a Marie Curie Fellowship of the European Community programme IHP (HPMF-CT-2001-01322).

The rational management of patients recovering from posttraumatic coma has been plagued by a paucity of hard data addressing the role of different physical interventions. In this paper, Oh and Seo present some useful and thorough research in a clinical area that is critically under-researched. As technology, knowledge and understanding advances, the number of patients surviving severe brain injury is increasing. Although the majority make a good recovery, a minority remain in coma, the minimally conscious state or the vegetative state. It has been estimated that as many as six to eight in 100 000 people each year sustain a moderate or severe head injury, with long-term consequences. Unfortunately, this is not reflected in the provision of health care or research effort in this field. These patients are often ignored by modern health care. While billions of research pounds and dollars have been spent on the investigation of (mainly ineffective) acute neuroprotective interventions, little research effort has been directed at dealing with the clinical reality of patients who are left severely disabled following brain injury. There should no longer be any doubt that early rehabilitation is essential to the effective care and long-term recovery of patients who have sustained a brain injury. As a result, the interface of clinical responsibility between acute care and rehabilitation has become increasingly blurred, with acute care teams taking greater responsibility for early rehabilitation (Von Wild, 2001). It is no longer appropriate to initiate rehabilitation only after acute care has come to an end, not only for self-evident logistic and clinical reasons, but also because the biology of acute inflammation following brain injury imperceptibly merges into processes involved in repair Correspondence: Leslie Gelling, Research Officer, School of Community Health and Social Studies, Anglia Polytechnic University, East Road, Cambridge, CB1 1PT, UK, E-mail: leslie.gelling@ntlworld.com

In this paper we present the results of an international survey among 313 CFOs o

Atmospheric CO2 concentration and temperature are increasing as a consequence of human activity. Periods of low water availability are expected to increase in Mediterranean ecosystems. Temperature gradient tunnels were used to provide near to ambient conditions and conditions simulating predicted increases in CO2 and temperature for an alfalfa crop. The performance, construction, and running costs of the tunnels are reported and discussed. Two levels of water supply were included in the treatments. Plants were grown in large, 13 L pots, keeping a fixed soil volumetric water content and with nodule fixation as the only nitrogen source for the plant. Regardless of water regime, the effect of elevated CO2 on plant growth was temperature dependent. Dry matter was enhanced when elevated CO2 and temperature were combined. Plant yield improvement was partly a result of increased photosynthetic rates. There were no effects on plant N concentration. Decreased specific nodule activity might suggest that lack of differences in plant N were a consequence of reduced nodule enzyme activity., This paper originates from an accompanyingmeasure OPTIMISE (Optimisation Of Water Use ByPlants In The Mediterranean) Contract Number:ICA3-CT-2002-50005 from European Commission programme INCO2: INCO-MED. This work was supported by the Spanish Ministry of Science and Technology (BFI2000-0154), Spanish Commission of Science and Technology (AMB96-0396) and Fundación Universitaria de Navarra. I. AranjueloMichelena was the recipient of a research grant fromSpanish Ministry of Science and Technology(FP2000-52313).

Lead antimonate yellow, or Naples Yellow, is one of the most common yellow pigments in Western European art. It was used mainly in the period from 1500 to 1850. During the 18th and 19th centuries, a whole range of production recipes was published. However, the early production history of the pigment is not well understood. In this paper, a study of two early production recipes is reported. Under the nomenclature of potters' yellow, the recipes describe some production details of the pigment. Reconstructions of the historical lead antimonate yellow were made according to these sources. X-ray powder diffraction (XRPD) was used to examine the reaction products. Our findings show that various types of lead antimonate yellow can be formed, following the descriptions given in the recipes. Some of these types, notably lead-tin antimonate, have been found in earlier studies of authentic works of art. No evidence was found for a locally limited use of this pigment, as has previously been suggested. Documentary and analytical evidence indicates that the knowledge on lead antimonate yellows originates from Middle Eastern ceramic and glass industries. it is argued that the know-how on the production of lead antimonate yellows has been transferred via the migration of glass artists from the Eastern Mediterranean to Venice during the 15th century.

‘Redlining’ is a form of place-based exclusion. It is widely documented in the US, but not in Europe. This paper focuses on a comparative analysis of redlining practices in the two largest cities of the Netherlands: Amsterdam and Rotterdam. It shows that redlining was common practice in Rotterdam in 1999. In 2001, no signs of redlining were found in Rotterdam. However, ‘yellowlining’ (lower loan-to-value ratios) was still common in some parts of Rotterdam. In Amsterdam, no neighbourhoods were faced with redlining in either 1999 or 2001. However, in 1999 some neighbourhoods were yellowlined. This paper aims to get a better understanding of the nature and the institutional context of redlining in the Netherlands by explaining how the differences in redlining practices between Amsterdam and Rotterdam, and between 1999 and 2001, can be explained. The National Mortgage Guarantee as well as socio-historical, and housing and mortgage market differences and changes, are instrumental in explaining these differences in redlining practices.

Professor Sir Alan Peacock has worked in cultural economics for over 35 years and he pioneered much of what is now the core subject matter of the field. This paper traces the development of his theoretical work on the economics of the arts, heritage and broadcasting, and shows how it interacted with his role as adviser to and chairman of several prestigious committees in the cultural sector. 'Subsidising the Arts involves the same kind of issues as subsidising particular industries or services in the economy, however distasteful this may seem to those who are conditioned to think in terms of a moral ordering of consumption expenditure ... Apart from any predisposition of the author to oppose paternalism, the assertion of any imposed value judgements is too easy a way of deriving support for public intervention designed to give the public not what it wants but what it ought to have!' (Peacock, 1969, p. 323). For a minor field of economics, cultural economics - the economics of the arts, heritage and cultural industries - has been blest with the attention of some major players: besides Keynes, Robbins and Baumol, whose contributions are sketched below, Ashenfelter, Boulding, Caves, Feldstein, Galbraith, Rosen, Scherer, Scitovsky and Shubik have all actively engaged in it, and Coase may also be included on account of his work on broadcasting. Some topics in cultural economics, such as museum entry charges, the finance of public service broadcasting and the size of the subsidy to opera, seem to be perennially controversial and the growing interest in cultural industries and the role of copyright look set to experience a similar future. As with other areas of applied economics, such as the economics of education, of the environment and of health, the analytical basis of cultural economics is welfare economics. It is no surprise, therefore, to find Peacock with his combined interest in welfare economics and cultural policy in this august company. Indeed, he may rightly be called primus inter pares, for he has arguably contributed to more areas of cultural economics than any of the others. Alan Peacock has had a long career as an economist, university teacher, university administrator, government adviser and arts administrator. He also has been an active composer and musician. He has continuously worked in cultural economics since the mid-1960s, having a seminal influence on its development, particularly, but by no means only, in the UK; he was in at the start of the subject and is still contributing to it. He has written his autobiography as a cultural economist, Paying the Piper (Peacock, 1993), in which he lays out his lifelong commitment to applying economics to understanding the arts, drawing on his * This paper was originally written for the Luce conference on 'Economists' case for government support of the Arts' organised in 2002 by Neil De Marchi and Crauford Goodwin of Duke University. I am grateful to Alan Peacock for his factual corrections to this article; also to William Baumol, Mark Blaug and Muriel Nissel for their helpful comments on an earlier draft and to three referees for theirs.

Objectives: The Stress Thermometer is an easily accessible Internet-based instrument for feedback on work stress and burnout. The aim of this paper is to describe the development of this instrument and to determine its applicability within the dental practice. Methods: The Stress Thermometer was made accessible to all members of the Dutch Dental Association, of which 77% of all Dutch dentists are members. Frequency of use was determined, and descriptive data was collected. Results: During an evaluation period of 5 months at least 12% of all possible respondents made use of the Stress Thermometer. Descriptive characteristics of the response group, as well as levels of burnout and work stress, corresponded with those found in the Dutch dentist population. However, some deviations were also present. Conclusions: Results indicate the applicability of the Stress Thermometer to a representative variety of dentists. Although the deviations found should not be ignored in future use, the Stress Thermometer was successful in reaching a population that is difficult to reach. It effectively calls attention to sensitive personal issues concerning work-related stress and burnout.

Based in part on the thesis submitted by E. Natividad for the degree of Doctor in Sciences from the Universidad de Zaragoza, Spain.-- Presented as an Oral Communication at the VII Congreso Nacional de Materiales, Madrid, Spain, October 2002., The fabrication of ceramic materials implies dealing with a great number of processing variables with clear interaction, which prevents straightforward optimization of the processes. In this paper, we report the optimization process applied to improve the properties of LFZ‐textured Bi‐2212 superconducting thin rods. In this process, based on Simplex optimization methods, four growth and four annealing parameters were taken as control variables to obtain high critical currents and short processing times. As a result, the critical current values increased by a factor of 3 after only 30 trials., This work was supported by the Spanish CICYT (Project MAT1999-1028 and 2002-04121-C03-02 and 03) and the CICYT and European Commission (Projects 2FD97-0546-C04-01 and -02). E. Natividad received a scholarship from the Spanish MCyT.

During the last decade, in many European countries and cities, area-based Urban Development Programmes have been initiated, in response to major problems of poverty and social exclusion. Urban Development Programmes are usually developed in a complex interplay between different governmental levels, and implemented by a wide variety of public and non-public parties. This paper addresses the organisation of these programmes, concentrating in particular on the form and extent of ‘public-public partnership’, i.e. on the role that the different levels of the public administration play, both through the administrative system and through policy-making. The ‘empirical’ basis for the paper consists of case studies, derived from the UGIS project (‘Urban Governance, Social Inclusion and Sustainability,’ a research project financed by the European Commission, DG RTD). The short analysis makes clear that both the model of public administration, in terms of the extent and form of decentralisation, and the presence (or lack) of a national policy framework determine the extent to which UDPs can be planned, approved and implemented at the local level. One of the main findings is that the central influence over UDPs depends more on the urban policy framework of the central government than on the model of public administration of a country. Countries with strong national (regional) urban policies, sufficient decentralisation of public administration to the municipal level and the use of governance methods at the local level open up possibilities for successful UDPs. Without upper-level urban policy frameworks UDPs might be successful as well, but their replicability and the control over their external effects will not be ensured.

The number of inhabitants of the four largest Dutch cities, Amsterdam, Rotterdam, The Hague and Utrecht, has stabilised since the mid-1980s. This stability in population size, however, hides considerable dynamics in population composition, especially regarding ethnicity, household type and socio-economic status. In this paper, we focus on the influence of international migration and residential migration flows on changing ethnic population structure. A selective residential outflow of natives and influx of foreigners, together with higher natural growth of ethnic minority groups, have contributed to very fast changes in ethnic composition of the four largest Dutch cities. The latest national population forecasts of Statistics Netherlands in December 2004 indicate an ongoing influx of foreign population groups into the Netherlands for the decades to come, despite the recent more restrictive immigration policy. One can expect from this a continuous international migration towards the large Dutch cities in particular. If the observed trend in native outflow continues, the foreign city population will soon cross the 50 per cent mark.

Aims: The suitability of genetic fingerprinting to study the microbiological basis of anaerobic bioreactor failure is investigated. Methods and Results: Two laboratory-scale anaerobic expanded granular sludge bed bioreactors, R1 and R2, were used for the mesophilic (37°C) treatment of high-strength [10 g chemical oxygen demand (COD) l−1] synthetic industrial-like wastewater over a 100-day trial period. A successful start up was achieved by both bioreactors with COD removal over 90%. Both reactors were operated under identical parameters; however, increased organic loading during the trial induced a reduction in the COD removal of R1, while R2 maintained satisfactory performance (COD removal >90%) throughout the experiment. Specific methanogenic activity measurements of biomass from both reactors indicated that the main route of methane production was hydrogenotrophic methanogenesis. Terminal restriction fragment length polymorphism (TRFLP) analysis was applied to the characterization of microbial community dynamics within the system during the trial. The principal differences between the two consortia analysed included an increased abundance of Thiovulum- and Methanococcus-like organisms and uncultured Crenarchaeota in R1. Conclusions: The results indicated that there was a microbiological basis for the deviation, in terms of operational performance, of R1 and R2. Significance and Impact of the Study: High-throughput fingerprinting techniques, such as TRFLP, have been demonstrated as practically relevant for biomonitoring of anaerobic reactor communities.

In this paper we analyse the renal transplant waiting list of the Pais Valencia in Spain, using Queueing theory. The customers of this queue are patients with end-stage renal failure waiting for a kidney transplant. We set up a simplified model to represent the flow of the customers through the system, and perform Bayesian inference to estimate parameters in the model. Finally, we consider several scenarios by tuning the estimations achieved and computationally simulate the behaviour of the queue under each one. The results indicate that the system could reach equilibrium at some point in the future and the model forecasts a slow decrease in the size of the waiting list in the short and middle term. Copyright (c) 2005 John Wiley & Sons, Ltd.

This paper analyses how outliers affect the identification of conditional heteroscedasticity and the estimation of generalized autoregressive conditionally heteroscedastic (GARCH) models. First, we derive the asymptotic biases of the sample autocorrelations of squared observations generated by stationary processes and show that the properties of some conditional homoscedasticity tests can be distorted. Second, we obtain the asymptotic and finite sample biases of the ordinary least squares (OLS) estimator of ARCH(p) models. The finite sample results are extended to generalized least squares (GLS), maximum likelihood (ML) and quasi-maximum likelihood (QML) estimators of ARCH(p) and GARCH(1,1) models. Finally, we show that the estimated asymptotic standard deviations are biased estimates of the sample standard deviations. Publicado

Gene expression profiles are composed of thousands of genes at the same time, representing the complex relationships between them. One of the well-known constraints specifically related to microarray data is the large number of genes in comparison with the small number of available experiments or cases. In this context, the ability of design methods capable of overcoming current limitations of state-of-the-art algorithms is crucial to the development of successful applications. This paper presentsgene-CBR, a hybrid model that can perform cancer classification based on microarray data. The system employs a case-based reasoning model that incorporates a set of fuzzy prototypes, a growing cell structure network and a set of rules to provide an accurate diagnosis. The hybrid model has been implemented and tested with microarray data belonging to bone marrow cases from forty-three adult patients with cancer plus a group of six cases corresponding to healthy persons.

19 páginas, 11 figuras, 6 tablas.-- El documento se encuentra en su versión post-print.-- et al., This paper analyses the spatial distribution of the inter-annual variability of vegetation activity in central Siberia and its relationship with atmospheric circulation variability. We used NOAA-AVHRR NDVI series from Pathfinder Land Data Set at 1° of spatial resolution, and we calculated the annual vegetation activity in each pixel (aNDVI) from 1982 to 2001. Principal component analysis (PCA) was used to determine the general spatial patterns of inter-annual variability of vegetation activity. We identified three main modes, which explain more than 50% of the total variance, each corresponding to a large region. By means of surface pressure grids, we analysed the main patterns of the seasonal atmospheric circulation in the study area: its variability was summarised by means of a few circulation modes and the patterns differ significantly between winter, spring and summer. However, a pattern with a North–South dipole structure represents the general spatial pattern of atmospheric circulation. We investigated the effect of seasonal atmospheric circulation patterns on the inter-annual variation of vegetation activity. In general, the strongest relationships between the atmospheric circulation variability, climate and the aNDVI variability were found in areas where the climatic characteristics are more limiting for the vegetation development, such as the northern regions. This may be explained by the fact that in these areas the variability of atmospheric circulation modes determines summer temperatures, which have a direct impact on vegetation activity., The authors wish to acknowledge financial support from the Siberia II project (5th Framework Program of the European Commission).

Over the last decade, the study of social interactions in economic decision making has become an important area of research. The main objective of this paper is to survey the extent to which recent empirical contributions have succeeded in overcoming the identification problems as first formulated by Manski (1993). This discussion is followed by a comparison of empirical studies in three key areas of research: neighborhood effects, substance use among teenagers, and peer effects among university roommates. Finally, I discuss questions like: Can economists restrict attention to a specific subcategories of social interactions? How do we define social groups, and what is the importance of social interactions for public policy?

This paper presents an essentially affine model of the term structure of interest rates making use of macroeconomic factors and their long-run expectations. The model extends the approach pioneered by Kozicki and Tinsley (2001) by modelling consistently long-run inflation expectations simultaneously with the term structure. This model thus avoids the standard pre-filtering of long-run expectations, as proposed by Kozicki and Tinsley (2001). Application to the U.S. economy shows the importance of long-run inflation expectations in the modelling of long-term bonds. The paper also provides a macroeconomic interpretation for the factors found in a latent factor model of the term structure. More specifically, we find that the standard "level" factor is highly correlated to long-run inflation expectations, the "slope" factor captures temporary business cycle conditions, while the "curvature" factor represents a clear independent monetary policy factor.