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Theoretical Arguments (theoretical + argument)
Selected AbstractsOn the measurement of growth with applications to the modelling and analysis of plant growthFUNCTIONAL ECOLOGY, Issue 2 2000Roderick M. L. Abstract 1.,In this paper, a theoretical framework for the analysis of growth is described. Growth is equated with change in volume (V) and the growth rate is given by the equation; dV/dt = (dm/dt)(1/,) , (d,/dt)(m/,2) where m is the mass and , the density. The volume is inclusive of internal air spaces. 2.,The second term of the growth equation (see above) can be ignored if density is constant over time. Data for humans (and presumably other large animals) show that while composition changes over time, the density is approximately constant at about that of water. In that case, the growth rate can be estimated from measures of the rate of change of mass. However, the density of plants is variable (c. 0·4,1·2 g cm,3) and measures of mass and density are necessary to analyse plant growth. 3.,To use the theory as the basis of plant growth models, it is necessary to develop simple methods for estimating the surface area of roots, stems and leaves assuming that the mass and volume are known. A literature review found that the surface area to volume ratios of leaves and roots generally increase with the mass concentration of water. Theoretical arguments are used to predict that in woody stems, the situation should be reversed such that the surface area to volume ratio increases with the mass concentration of dry matter. Those relationships should be very useful in the development of plant growth models. 4.,Measures of plant dry mass and estimates of the rate of change in dry mass are shown to be very difficult to interpret because of differences in the mass concentration of dry matter between individuals and over time. 5.,It is concluded that measures of mass and density will be necessary before plant growth analysis can achieve its full potential. A framework for extending the theory to include the forces necessary for growth to occur is described. [source] Contextualizing Research on Social Capital in Regional ClustersINTERNATIONAL JOURNAL OF URBAN AND REGIONAL RESEARCH, Issue 3 2007UDO STABER Abstract Numerous works in economic geography and regional studies have considered social capital a salient factor in the performance of regional business clusters. Theoretical arguments have focused on those structural, relational and cognitive features of social capital that are expected to facilitate cooperation and innovation as a basis for cluster success. However, the available empirical evidence on the performance implications of social capital is weak and largely inconsistent. I argue that one reason for the observed cross-study inconsistencies is the neglect of the situational context in which social capital evolves. I discuss how acontextual studies can lead to analytical error and flawed conclusions concerning the performance outcomes of social capital. I propose several approaches to contextualizing research and discuss how they would advance our understanding of the performance implications of social capital in a cluster setting. Résumé De nombreux travaux de géographie économique et études régionales voient dans le capital social un facteur fondamental de la réussite des pôles d'entreprises régionaux. Les discussions théoriques ont porté sur les caractéristiques structurelles, relationnelles et cognitives du capital social qui sont censées faciliter coopération et innovation, composantes de base de la réussite de ces pôles. Toutefois, les preuves empiriques disponibles des implications du capital social dans cette réussite sont fragiles et peu cohérentes. Cet article affirme que les incohérences des études croisées tiennent, pour une part, à l'ignorance du contexte situationnel dans lequel évolue le capital social. Il expose comment des études hors contexte peuvent conduire à une erreur analytique et à des conclusions incorrectes quant aux résultats générés par le capital social. Il propose plusieurs approches pour placer les recherches en contexte et analyse comment, grâce à elles, nous pourrions mieux comprendre la part de réussite propre au capital social dans le cadre d'un pôle donné. [source] Does Public Service Motivation Adapt?KYKLOS INTERNATIONAL REVIEW OF SOCIAL SCIENCES, Issue 2 2010Yannis Georgellis SUMMARY Theoretical arguments highlight the importance of Public Service Motivation (PSM) in underpinning employment relationships in the public sector, mainly based on the presumption that many aspects of public service provision are non-contractible. Consequently, hiring workers who are public service, or pro-socially, motivated helps to overcome incentive problems and to increase organizational efficiency, thus reducing the need for high-powered incentives. However, such an argument would be undermined should workers' pro-social or intrinsic motivation dissipates rapidly with job tenure. Based on longitudinal data from the British Household Panel Survey (BHPS), we explore patterns of overall and domain satisfaction measures for workers who made the transition from private to public sector employment. We are particularly interested in finding out whether any possible boost in satisfaction with the nature of the work itself, our proxy for pro-social or Public Service Motivation (PSM), associated with accepting public sector employment dissipates following the transition into public sector employment. Our results reject the hypothesis of a rapid and complete adaptation of PSM back to baseline or pre-transition levels. Interestingly, this is not the case for public to private or for within-sector transitions, which result in a short-lived increase in intrinsic motivation. This is welcome evidence for the advocates of the benefits of having pro-socially or intrinsically motivated people working in the public sector. [source] Effects of cord motion on diffusion imaging of the spinal cordMAGNETIC RESONANCE IN MEDICINE, Issue 2 2006Hardave S. Kharbanda Abstract Measurement of diffusion and its dependence on direction has become an important tool for clinical and research studies of the brain. Diffusion imaging of the spinal cord may likewise prove useful as an indicator of tissue damage and axonal integrity; however, it is more challenging to perform diffusion imaging in the cord than in the brain. Here we report a study of the effects of motion on single-shot fast spin echo (FSE) diffusion tensor imaging (DTI) of the spinal cord. Diffusion imaging was performed at four different times in the cardiac cycle both without and with velocity compensation of the diffusion gradients. Uncompensated diffusion images demonstrated substantial signal loss artifacts in the cord that were strongly dependent on the delay after the pulse-oximeter trigger. Quantitative diffusion analysis was also strongly affected by this motion artifact. The use of flow-compensated gradients helped to restore normal signal in the cord, especially at particular trigger delays. Theoretical arguments suggest that improved spatial resolution may help eliminate this signal loss. Even with higher spatial resolution, motion-related signal attenuation may still occur in diffusion imaging of pathologies that alter the motion of the cord. However, this same cord motion may contain diagnostically valuable information when probed using appropriate diffusion imaging approaches. Magn Reson Med, 2006. © 2006 Wiley-Liss, Inc. [source] Effects of inductive coupling on parallel MR image reconstructionsMAGNETIC RESONANCE IN MEDICINE, Issue 3 2004Michael A. Ohliger Abstract Theoretical arguments and experimental results are presented that characterize the impact of inductive coupling on the performance of parallel MRI reconstructions. A simple model of MR signal and noise reception suggests that the intrinsic amount of spatial information available from a given coil array is unchanged in the presence of inductive coupling, as long as the sample remains the dominant source of noise for the coupled array. Any loss of distinctness in the measured coil sensitivities is compensated by information stored in the measured noise correlations. Adjustments to the theory are described to account for preamplifier noise contributions. Results are presented from an experimental system in which preamplifier input impedances are systematically adjusted in order to vary the level of coupling between array elements. Parallel image reconstructions using an array with four different levels of coupling and an acceleration factor up to six show average SNR changes of ,7.6% to +7.5%. The modest changes in overall SNR are accompanied by similarly small changes in g-factor. These initial results suggest that moderate amounts of inductive coupling should not have a prohibitive effect on the use of a given coil array for parallel MRI. Magn Reson Med 52:628,639, 2004. © 2004 Wiley-Liss, Inc. [source] Scale-dependent galaxy bias in the Sloan Digital Sky Survey as a function of luminosity and colourMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 2 2009James G. Cresswell ABSTRACT It has been known for a long time that the clustering of galaxies changes as a function of galaxy type. This galaxy bias acts as a hindrance to the extraction of cosmological information from the galaxy power spectrum or correlation function. Theoretical arguments show that a change in the amplitude of the clustering between galaxies and mass on large scales is unavoidable, but cosmological information can be easily extracted from the shape of the power spectrum or correlation function if this bias is independent of scale. Scale-dependent bias is generally small on large scales, k < 0.1 h Mpc,1, but on smaller scales can affect the recovery of ,mh from the measured shape of the clustering signal, and have a small effect on the Baryon Acoustic Oscillations. In this paper, we investigate the transition from scale-independent to scale-dependent galaxy bias as a function of galaxy population. We use the Sloan Digital Sky Survey Data Release 5 sample to fit various models, which attempt to parametrize the turn-off from scale-independent behaviour. For blue galaxies, we find that the strength of the turn-off is strongly dependent on galaxy luminosity, with stronger scale-dependent bias on larger scales for more luminous galaxies. For red galaxies, the scale dependence is a weaker function of luminosity. Such trends need to be modelled in order to optimally extract the information available in future surveys, and can help with the design of such surveys. [source] Four-dimensional variational assimilation in the unstable subspace and the optimal subspace dimensionTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 647 2010Anna Trevisan Abstract Key apriori information used in 4D-Var is the knowledge of the system's evolution equations. In this article we propose a method for taking full advantage of the knowledge of the system's dynamical instabilities in order to improve the quality of the analysis. We present an algorithm for four-dimensional variational assimilation in the unstable subspace (4D-Var , AUS), which consists of confining in this subspace the increment of the control variable. The existence of an optimal subspace dimension for this confinement is hypothesized. Theoretical arguments in favour of the present approach are supported by numerical experiments in a simple perfect nonlinear model scenario. It is found that the RMS analysis error is a function of the dimension N of the subspace where the analysis is confined and is a minimum for N approximately equal to the dimension of the unstable and neutral manifold. For all assimilation windows, from 1 to 5 d, 4D-Var , AUS performs better than standard 4D-Var. In the presence of observational noise, the 4D-Var solution, while being closer to the observations, is farther away from the truth. The implementation of 4D-Var , AUS does not require the adjoint integration. Copyright © 2010 Royal Meteorological Society [source] Determining the character of motion in quiet and active galaxies with a satellite companionASTRONOMISCHE NACHRICHTEN, Issue 1 2009N.D. Caranicolas Abstract A galaxy model with a satellite companion is used to study the character of motion for stars moving in the x - y plane. It is observed that a large part of the phase plane is covered by chaotic orbits. The percentage of chaotic orbits increases when the galaxy has a dense nucleus of massMn. The presence of the dense nucleus also increases the stellar velocities near the center of the galaxy. For small values of the distance R between the two bodies, low energy stars display a chaotic region near the centre of the galaxy, when the dense nucleus is present, while for larger values of R the motion in active galaxies is regular for low energy stars. Our results suggest that in galaxies with a satellite companion, the chaotic character of motion is not only a result of galactic interaction but also a result caused by the dense nucleus. Theoretical arguments are used to support the numerical outcomes. We follow the evolution of the galaxy, as mass is transported adiabatically from the disk to the nucleus. Our numerical results are in satisfactory agreement with observational data from M51-type binary galaxies (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Investigating the efficacy of concept mapping with pupils with autistic spectrum disorderBRITISH JOURNAL OF SPECIAL EDUCATION, Issue 3 2007Veronica Roberts Pupils with autism often present significant challenges to teachers. They seem to have real strengths in visual processing but a cognitive style that encourages them to focus on detail rather than the overarching connections between concepts. Veronica Roberts, currently undertaking doctoral training at the Institute of Education, University of London, in order to become an educational psychologist, and Richard Joiner, senior lecturer in the Department of Psychology at the University of Bath, set out to explore these issues. In this article, they report the outcomes of a naturalistic experiment in which they investigated the utility of concept mapping as an educational strategy with pupils diagnosed with an autistic spectrum disorder (ASD). Theoretical arguments supporting the use of concept mapping with an autistic population are outlined in the paper. A tutor group of ten pupils with ASD, aged between 11 and 14 years, took part in the study. Concept mapping tasks were integrated within National Curriculum science lessons in collaboration with the school's science teacher. The study found that the increase in pupil performance in subject-specific questionnaires was nearly four times greater in the concept mapping condition than after a more conventional teaching intervention. Veronica Roberts and Richard Joiner tentatively draw out the implications of their work for staff who work with pupils with ASD and make recommendations for further research into the use of these learning strategies. [source] Generalized Birnbaum-Saunders distributions applied to air pollutant concentrationENVIRONMETRICS, Issue 3 2008Víctor Leiva Abstract The generalized Birnbaum-Saunders (GBS) distribution is a new class of positively skewed models with lighter and heavier tails than the traditional Birnbaum-Saunders (BS) distribution, which is largely applied to study lifetimes. However, the theoretical argument and the interesting properties of the GBS model have made its application possible beyond the lifetime analysis. The aim of this paper is to present the GBS distribution as a useful model for describing pollution data and deriving its positive and negative moments. Based on these moments, we develop estimation and goodness-of-fit methods. Also, some properties of the proposed estimators useful for developing asymptotic inference are presented. Finally, an application with real data from Environmental Sciences is given to illustrate the methodology developed. This example shows that the empirical fit of the GBS distribution to the data is very good. Thus, the GBS model is appropriate for describing air pollutant concentration data, which produces better results than the lognormal model when the administrative target is determined for abating air pollution. Copyright © 2007 John Wiley & Sons, Ltd. [source] Legislatures, Legitimacy and Crises: The Relationship Between Representation and Crisis ManagementJOURNAL OF CONTINGENCIES AND CRISIS MANAGEMENT, Issue 1 2010Alastair Stark This article presents a theoretical argument that the study of representation can yield important insights for crisis analysts. The argument is presented through a claim that the representative systems, legislatures and individuals of a state , defined here broadly as ,representative institutions', should be factored into political analyses of crisis management, as they provide a lens for novel explorations of crisis issues. In particular, the use of parliamentary perspectives, and the examination of specific legislature functions during crises, can lead to valuable insights into the legitimacy dynamics that characterize political crisis episodes. [source] ,Low' fertility and population replacement in ScotlandPOPULATION, SPACE AND PLACE (PREVIOUSLY:-INT JOURNAL OF POPULATION GEOGRAPHY), Issue 1 2007John MacInnes Abstract It has been argued that Scotland faces population ageing and decline that will have potentially serious economic and social consequences, and that the origin of these processes lie in its low and declining fertility rates. After considering alternatives to the total period rate measure of fertility, empirical evidence and theoretical argument about low fertility and its consequences is briefly reviewed. The paper argues that low fertility in general may not be the problem it is often purported to be, that Scotland has relatively high fertility, and that pro-natalist policies are neither desirable nor necessary. It suggests that low fertility and population ageing may be viewed as positive developments, and that within Europe, Scotland is distinguished more by its excess of early deaths than by any shortage of births. Copyright © 2007 John Wiley & Sons, Ltd. [source] National growth versus spatial equality?REGIONAL SCIENCE POLICY AND PRACTICE, Issue 1 2008A cautionary note on the new, trade-off' thinking in regional policy discourse national efficiency; regional equity; trade-offs; regional policy Abstract Recently, there has been increasing interest in whether and to what extent the spatial agglomeration or concentration of economic activity and employment in particular regions may actually benefit national growth. The implication is that policies that seek to reduce regional economic inequality may in fact be nationally inefficient: in other words, that a policy ,trade-off' may exist between the pursuit of national growth and the reduction of regional economic disparities. This view has been particularly associated with the so-called ,new economic geography' models, and seems to be circulating in official policy circles. This paper suggests that neither the theoretical argument nor the empirical evidence for a national efficiency-regional equity trade-off are yet convincing, and that until much more research has been undertaken on both fronts policy-makers should exercise caution in appealing to this supposed trade-off notion to justify particular policy choices. [source] Getting out of the habitus: an alternative model of dynamically embodied social actionTHE JOURNAL OF THE ROYAL ANTHROPOLOGICAL INSTITUTE, Issue 3 2000Brenda Farnell Although Bourdieu's theory of practice has drawn widespread attention to the role of the body and space in social life, the concept of habitus is problematic as an explanatory account of dynamic embodiment because it lacks an adequate conception of the nature and location of human agency. An alternative model is presented which locates agency in the causal powers and capacities of embodied persons to engage in dialogic, signifying acts. Grounded in a non-Cartesian concept of person and ,new realist', post-positivist philosophy of science, vocal signs and action signs, not the dispositions of a habitus, become the means by which humans exercise agency in dynamically embodied practices. Ethnographic data from the communicative practices of the Nakota (Assiniboine) people of northern Montana (USA) support and illustrate the theoretical argument. [source] Ethical investment and the incentives for corporate environmental protection and social responsibilityCORPORATE SOCIAL RESPONSIBILITY AND ENVIRONMENTAL MANAGEMENT, Issue 4 2003Iulie Aslaksen This paper addresses some interrelated questions regarding ethical investments: does ethical screening provide any incentives for improved social responsibility within firms? Are ethical screened portfolios competitive compared with conventional funds with respect to risk-adjusted return? Does the risk-adjusted return of a screened portfolio depend on the screening strategy applied? Considering ethical screening as a kind of segmentation of the equity market, it is shown that screening might create incentives for changes in firms' behaviour. The strength of this incentive depends on the relative share of screened portfolios, which in turn partially depends on the financial performance of the screened portfolios. While some theoretical arguments suggest that screening imposes a handicap compared with conventional portfolios, the empirical evidence does not suggest that screened portfolios systematically under-perform conventional portfolios. Copyright © 2003 John Wiley & Sons, Ltd and ERP Environment. [source] Industrial Agglomeration and Development: A Survey of Spatial Economic Issues in East Asia and a Statistical Analysis of Chinese RegionsECONOMIC GEOGRAPHY, Issue 3 2003C. Cindy Fan Abstract: In this article, we explore the issue of industrial agglomeration and its relationship to economic development and growth in the less-developed countries of East Asia. We present theoretical arguments and secondary empirical evidence as to why we should have strong expectations about finding a positive relationship between agglomeration and economic performance. We also review evidence from the literature on the roles of formal and informal institutions in East Asian regional economic systems. We then focus specifically on the case of China. We argue that regional development in China has much in common with regional development in other East Asian economies, although there are also important contrasts because of China's history of socialism and its recent trend toward economic liberalization. Through a variety of statistical investigations, we substantiate (in part) the expected positive relationship between agglomeration and economic performance in China. We show that many kinds of manufacturing sectors are characterized by a strong positive relationship between spatial agglomeration and productivity. This phenomenon is especially marked in sectors and regions where liberalization has proceeded rapidly. We consider the relevance of our comments about industrial clustering and economic performance for policy formulation in China and the less-developed countries of East Asia. [source] Foreign direct investment and the dark side of decentralizationECONOMIC POLICY, Issue 49 2007Sebastian G. Kessing SUMMARY Fiscal decentralization VERTICAL, HORIZONTAL, AND FDI Both in the developed and developing world, decentralization of fiscal policy is frequently argued to foster investment, because allowing investors to choose between competing locations should make it difficult for each jurisdiction to tax the investment's returns. We point out that this ,horizontal' dimension of decentralization cannot eliminate ex post incentives to tax investments once they are irreversibly located in a jurisdiction, and that the negative ex ante investment effects of such ,hold up' problems are actually stronger when decentralization inevitably leads to multiple levels of taxation power in each location. Empirically, we detect significant negative effects on FDI of the ,vertical' dimension of decentralization, measured by the number of government layers, in a data set containing many countries and many suitable control variables. Indicators of overall fiscal decentralization do not appear to affect the investment climate negatively per se, but our theoretical arguments and empirical results suggest that policymakers should consider very carefully the form and degree of government decentralization if they aim at improving the investment climate. , Sebastian G. Kessing, Kai A. Konrad and Christos Kotsogiannis [source] The political economy of direct legislation: direct democracy and local decision,makingECONOMIC POLICY, Issue 33 2001Lars P Feld Local and regional governments account for an important share of total government spending and, given the decentralization trend in OECD nations, this is likely to increase. How should this spending be governed? This article argues that direct democracy is best suited to organize decision,making at the state and local level. To support this, we present the main theoretical arguments on why and how referenda and initiatives affect fiscal policy outcomes. The basic argument concerns voter control. Under representative democracy, citizens only have direct control at election time. With referenda and initiatives, citizens can selectively control their representatives on specific policies whenever they deviate sufficiently from citizens' preferences. As a result, fiscal policy outcomes are likely to more closely reflect voter preferences. We empirically test this on Swiss data since Switzerland provides a ,natural laboratory' for local governance. The governance structures of Swiss cantons and localities with respect to fiscal issues range from classic parliamentary democracy to pure direct democracy, and an important part of spending and taxation is controlled at these levels. Specifically, we estimate an econometric model of fiscal behaviour using data from 1986 to 1997 for the 26 Swiss cantons, and 1990 data on 134 local communities. It is shown that mandatory referenda on fiscal issues at both levels have a dampening effect on expenditure and revenue, and at the local level also on public debt. Combining this with existing empirical evidence leads to a relatively uncontested result, namely that elements of direct democracy are associated with sounder public finances, better economic performance and higher satisfaction of citizens. [source] THE LOCUS OF EVOLUTION: EVO DEVO AND THE GENETICS OF ADAPTATIONEVOLUTION, Issue 5 2007Hopi E. Hoekstra An important tenet of evolutionary developmental biology ("evo devo") is that adaptive mutations affecting morphology are more likely to occur in the cis -regulatory regions than in the protein-coding regions of genes. This argument rests on two claims: (1) the modular nature of cis -regulatory elements largely frees them from deleterious pleiotropic effects, and (2) a growing body of empirical evidence appears to support the predominant role of gene regulatory change in adaptation, especially morphological adaptation. Here we discuss and critique these assertions. We first show that there is no theoretical or empirical basis for the evo devo contention that adaptations involving morphology evolve by genetic mechanisms different from those involving physiology and other traits. In addition, some forms of protein evolution can avoid the negative consequences of pleiotropy, most notably via gene duplication. In light of evo devo claims, we then examine the substantial data on the genetic basis of adaptation from both genome-wide surveys and single-locus studies. Genomic studies lend little support to the cis -regulatory theory: many of these have detected adaptation in protein-coding regions, including transcription factors, whereas few have examined regulatory regions. Turning to single-locus studies, we note that the most widely cited examples of adaptive cis -regulatory mutations focus on trait loss rather than gain, and none have yet pinpointed an evolved regulatory site. In contrast, there are many studies that have both identified structural mutations and functionally verified their contribution to adaptation and speciation. Neither the theoretical arguments nor the data from nature, then, support the claim for a predominance of cis -regulatory mutations in evolution. Although this claim may be true, it is at best premature. Adaptation and speciation probably proceed through a combination of cis -regulatory and structural mutations, with a substantial contribution of the latter. [source] CAN INTRASPECIFIC COMPETITION DRIVE DISRUPTIVE SELECTION?EVOLUTION, Issue 3 2004AN EXPERIMENTAL TEST IN NATURAL POPULATIONS OF STICKLEBACKS Abstract Theory suggests that frequency-dependent resource competition will disproportionately impact the most common phenotypes in a population. The resulting disruptive selection forms the driving force behind evolutionary models of niche diversification, character release, ecological sexual dimorphism, resource polymorphism, and sympatric speciation. However, there is little empirical support for the idea that intraspecific competition generates disruptive selection. This paper presents a test of this theory, using natural populations of the three-spine stickleback, Gasterosteus aculeatus. Sticklebacks exhibit substantial individual specialization associated with phenotypic variation and so are likely to experience frequency-dependent competition and hence disruptive selection. Using body size and relative gonad mass as indirect measures of potential fecundity and hence fitness, I show that an important aspect of trophic morphology, gill raker length, is subject to disruptive selection in one of two natural lake populations. To test whether this apparent disruptive selection could have been caused by competition, I manipulated population densities in pairs of large enclosures in each of five lakes. In each lake I removed fish from one enclosure and added them to the other to create paired low- and high-population-density treatments with natural phenotype distributions. Again using indirect measures of fitness, disruptive selection was consistently stronger in high-density than low-density enclosures. These results support long-standing theoretical arguments that intraspecific competition drives disruptive selection and thus may be an important causal agent in the evolution of ecological variation. [source] Towards a Semiology of the Periodic Review of UK Regulated UtilitiesFINANCIAL ACCOUNTABILITY & MANAGEMENT, Issue 3 2001Stuart Cooper This note explores the regulatory process of UK privatised utilities through the periodic review of prices. It provides a brief history of the privatisation programme in the UK and the theoretical arguments for the price-cap regulation that has been used. It argues that regulatory process appears to involve a covert dialogue and exchange of information between the regulator and regulated and also a second separate review process that consists of an overt dialogue. Using a semiotic analysis the authors suggest that the unfolding of each of these overt reviews follows a very similar pattern that is constantly being re-enacted. It is concluded that further research is required into the relative importance of the two separate review processes in the setting of the price-cap. [source] Do Unions Benefit from Working in Partnership with Employers?INDUSTRIAL RELATIONS, Issue 4 2008Evidence from Ireland Advocates and critics of voluntary workplace partnership have presented a series of theoretical arguments as to the potential consequences for unions working under partnership arrangements. A survey of Irish employees' views is used to assess these competing claims. The study is timely on two counts: first, empirical investigations of the effects of partnership on union influence and members' commitment to unions are rare; and, second, it is 11 years since employers, unions, and government in Ireland first signed a national framework agreement to promote the diffusion of partnership as a means for the handling of workplace change. The evidence provides support for the arguments as advanced by advocates. [source] Stanford School on Sociological Institutionalism: A Global Cultural Approach,INTERNATIONAL POLITICAL SOCIOLOGY, Issue 3 2010Didem Buhari-Gulmez Stanford School,World Society or World Polity approach,led by John W. Meyer has been largely overlooked despite its revolutionary insights (Robertson 2009). Nevertheless, renewed interest in neoinstitutionalisms and concepts as world society, culture, and legitimacy (Clark 2007) imply Stanford School's relevance for contemporary social and political sciences. This essay discusses first, the underlying theoretical arguments of the School, second, its main findings and responses to criticisms, and third, Stanford School's resonance with the Constructivist, Neoinstitutionalist, and Sociological turns in International Relations. Finally, it suggests that Stanford School opens new horizons for EU studies by establishing the "missing link" between globalization and European integration. [source] The Impact of Asia on World Politics: China and India Options for the United States,INTERNATIONAL STUDIES REVIEW, Issue 4 2006RONALD L. TAMMEN The United States, by concentrating its intellectual, diplomatic, and military energy on the Middle East, is neglecting the far more substantial long-range challenges that will arise in Asia by mid-century. This strategic myopia is magnified by the lack of a clear national strategy, one that should be focused on recognizing the full implications of the rise of China and India into the ranks of great powers. Informed by theoretical arguments and offering policy options, this essay examines the coming Asian challenge against the backdrop of a world with three great powers potentially competing for resources, allies, and leadership within Asia and, more broadly, the international system. [source] Are weed population dynamics chaotic?JOURNAL OF APPLIED ECOLOGY, Issue 5 2002Robert P. Freckleton Summary 1There have been suggestions that the population dynamics of weeds may show chaotic dynamics, and that therefore it will not be possible to predict the impact of changing management regimes on weed abundance. The instability of weed populations is presumed to result either from overcompensating yield,density responses or from threshold management. 2Using theoretical arguments and empirical evidence we argue that this contention is likely to be incorrect. 3Overcompensating yield,density responses are unlikely in plant populations and this point has been extensively discussed. Such responses have only been observed in high-density artificially sown stands of weed populations. The form of chaos that results from threshold management is a consequence of high population growth resulting from the cessation of management when weed densities are lower than a threshold level. Consequently the dynamics of such populations may be argued to be extrinsically rather than intrinsically driven. 4There are many studies that have shown weed populations to be dynamically stable, both spatially and temporally. Here we present an analysis of data from the Broadbalk experiment that demonstrates long-term stability of 12 species of common weeds over a 12-year period. Using parameter estimates derived from the literature we show that the stability of these populations is similar to other annual species, both weedy and non-weedy. 5We argue that weed population dynamics are more generally better viewed as resulting from the impacts of broad-scale types of management, as well as temporal variability in population numbers. The significance of chaotic dynamics is likely to be minimal. [source] Genome size and recombination in angiosperms: a second lookJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 2 2007J. ROSS-IBARRA Abstract Despite dramatic differences in genome size , and thus space for recombination to occur , previous workers found no correlation between recombination rate and genome size in flowering plants. Here I re-investigate these claims using phylogenetic comparative methods to test a large data set of recombination data in angiosperms. I show that genome size is significantly correlated with recombination rate across a wide sampling of species and that change in genome size explains a meaningful proportion (,20%) of variation in recombination rate. I show that the strength of this correlation is comparable with that of several characters previously linked to evolutionary change in recombination rate, but argue that consideration of processes of genome size change likely make the observed correlation a conservative estimate. And finally, although I find that recombination rate increases less than proportionally to change in genome size, several mechanistic and theoretical arguments suggest that this result is not unexpected. [source] A classifying procedure for signalling turning pointsJOURNAL OF FORECASTING, Issue 3 2004Lasse Koskinen Abstract A Hidden Markov Model (HMM) is used to classify an out-of-sample observation vector into either of two regimes. This leads to a procedure for making probability forecasts for changes of regimes in a time series, i.e. for turning points. Instead of estimating past turning points using maximum likelihood, the model is estimated with respect to known past regimes. This makes it possible to perform feature extraction and estimation for different forecasting horizons. The inference aspect is emphasized by including a penalty for a wrong decision in the cost function. The method, here called a ,Markov Bayesian Classifier (MBC)', is tested by forecasting turning points in the Swedish and US economies, using leading data. Clear and early turning point signals are obtained, contrasting favourably with earlier HMM studies. Some theoretical arguments for this are given. Copyright © 2004 John Wiley & Sons, Ltd. [source] What If Immigrants Had Not Migrated?AMERICAN JOURNAL OF ECONOMICS AND SOCIOLOGY, Issue 2 2005Consequence of Korean Immigration to the United States, Determinants Despite strong theoretical arguments and models about international migration, very few empirical studies rigorously test these arguments and models. The purpose of the present study is to analyze determinants and consequences for international migration, focusing particularly on the returns to post-hoc international migration. The present study compares residential well-being of Korean international migrants in the United States with that of their hypothetical well-being if they had not migrated. Our suggested models of the selectivity corrected returns to various characteristics for immigrants and nonimmigrants enable us to estimate the "opportunity well-being" of individuals and households; that is, the well-being of immigrants-had-they-stayed and of nonimmigrants-if-they-had-immigrated. The data for our analyses are drawn from the 1990 Korea Census Data and the Public Use Microdata Samples (PUMS) of the 1990 U.S. Census. In either case of migrants-had-they-stayed or of nonimmigrants-had-they-migrated, international migration to the United States has a significant and positive effect on the probability of homeownership, especially for women. The results show that the predicted probability of homeownership attainment increases as a result of migration by 15 percent to 16 percent for women and by 8 percent for men. The study concludes that migrating to the United States offers better opportunities for homeownership than staying in Korea does, particularly for women. [source] Targeted Pharmacotherapy of Evoked Phenomena in Neuropathic Pain: A Review of the Current EvidencePAIN MEDICINE, Issue 1 2007BSc(Med), Ron Granot MB BS ABSTRACT Objective., Evoked phenomena in clinical neuropathic pain are viewed as a window into the underlying pathophysiology. They are also potential therapeutic targets. This study sought evidence for the effect on such evoked phenomena of currently used agents. Design., We reviewed MEDLINE (1966,2006) and EMBASE (1980,2006) to locate all randomized, double-blind, placebo-controlled trials examining therapeutic responses of evoked neuropathic pain phenomena, including dynamic mechanical allodynia, pin prick hyperalgesia, and thermal allodynia. We also noted the methods of elicitation of these evoked pain phenomena. Results., We found 40 articles meeting our inclusion criteria. A wide variety of methods was used to evoke neuropathic pain phenomena. For dynamic mechanical allodynia, there is some evidence for the efficacy of ketamine, alfentanil, and morphine, but only when administered intravenously. For other agents and other evoked pain phenomena, there is insufficient evidence to draw firm conclusions. Conclusions., There is minimal evidence to guide clinicians in treating evoked pain phenomena in clinical neuropathic pain states. There is little clinical evidence to either support or refute theoretical arguments for efficacy of specific agents in evoked neuropathic pain phenomena. More and larger trials are needed to examine these phenomena. Consensus is required with respect to methods used to elicit these evoked phenomena. [source] Empirical growth models with spatial effects*PAPERS IN REGIONAL SCIENCE, Issue 2 2006Bernard Fingleton Spatial spillovers; regional productivity; spatial econometrics; EU regions Abstract., Recent contributions to the regional science literature have considered spatial effects in empirical growth specifications. In the case of spatial dependence, following theoretical arguments from new economic geography, and endogenous growth models, this phenomenon has been associated with the existence of externalities that cross regional borders. However, despite the general consensus that interactions or externalities are likely to be the major source of spatial dependence, they have been modelled in a rather ad hoc manner in most existing empirical studies. In contrast, we advocate basing the analysis on structural growth models which include externalities across economies, applying the appropriate spatial econometrics tools to test for their presence and estimate the magnitude of these externalities in the real world. [source] | ||||||||||||||||||||||||||||||||||