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Reference Point (reference + point)
Kinds of Reference Point Selected AbstractsLocal Influence Diagnostics for Quasi-Likelihood and Lognormal Estimates of a Biological Reference Point from Some Fish Stock and Recruitment ModelsBIOMETRICS, Issue 3 2006N. G. Cadigan Summary We present local influence diagnostics to measure the sensitivity of a biological limit reference point (LRP) estimated from fitting a model to stock and recruitment data. LRPs are low levels of stock size that the management of commercial fisheries should avoid with high probability. The LRP we examine is the stock size at which recruitment is 50% of the maximum (S50%). We derive analytic equations to describe the effects on S50% of changing the weight that observations are given in estimation. We derive equations for the Ricker, Beverton,Holt, and hockey-stick stock-recruit models, and four estimation methods including the error sums of squares method on log responses and three quasi-likelihood methods. We conclude from case studies that the hockey-stick model produces the most robust estimates. [source] Economica Coase Lecture: Reference Points and the Theory of the FirmECONOMICA, Issue 299 2008OLIVER HART I argue that it has been hard to make progress on Coase's theory of the firm agenda because of the difficulty of formalizing haggling costs. I propose an approach that tries to move things forward using the idea of aggrievement costs, and apply it to the question of whether a transaction should be placed inside a firm (in-house production) or in the market place (outsourcing). [source] Reserve Prices in Auctions as Reference Points,THE ECONOMIC JOURNAL, Issue 520 2007Stephanie Rosenkranz We consider second-price and first-price auctions in the symmetric independent private values framework. We modify the standard model by the assumption that the bidders have reference-based utility, where a publicly announced reserve price has some influence on the reference point. It turns out that the seller's optimal reserve price increases with the number of bidders. Also in contrast to the standard model, we find that secret reserve prices can outperform public reserve prices, and that setting the optimal reserve price can be more valuable for the seller than attracting additional bidders. [source] Applying fuzzy logic and genetic algorithms to enhance the efficacy of the PID controller in buffer overflow elimination for better channel response timeliness over the InternetCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 7 2006Wilfred W. K. Lin Abstract In this paper two novel intelligent buffer overflow controllers: the fuzzy logic controller (FLC) and the genetic algorithm controller (GAC) are proposed. In the FLC the extant algorithmic PID controller (PIDC) model, which combines the proportional (P), derivative (D) and integral (I) control elements, is augmented with fuzzy logic for higher control precision. The fuzzy logic divides the PIDC control domain into finer control regions. Every region is then defined either by a fuzzy rule or a ,don't care' state. The GAC combines the PIDC model with the genetic algorithm, which manipulates the parametric values of the PIDC as genes in a chromosome. The FLC and GAC operations are based on the objective function . The principle is that the controller should adaptively maintain the safety margin around the chosen reference point (represent by the ,0' of ) at runtime. The preliminary experimental results for the FLC and GAC prototypes indicate that they are both more effective and precise than the PIDC. After repeated timing analyses with the Intel's VTune Performer Analyzer, it was confirmed that the FLC can better support real-time computing than the GAC because of its shorter execution time and faster convergence without any buffer overflow. Copyright © 2005 John Wiley & Sons, Ltd. [source] The Birth of the CAP Die Geburt der GAP La naissance de la PACEUROCHOICES, Issue 2 2008David R. Stead Summary The Birth of the CAP Fifty years ago, a Conference was held at Stresa which could be said to be the single event that most appropriately marks the birth of the CAP. Although five policy objectives had been written into the 1957 Treaty of Rome, these have been widely criticised for being vague and contradictory, and the Treaty contained very few stipulations on the specific policy instruments to be adopted. The Stresa Conference made important, but incomplete, progress towards finalising the policy framework. Most notably, it was generally agreed to avoid a level of price support that created unwanted commodity surpluses and inhibited structural adjustment. But these good intentions, and the positive ,European spirit' of the Conference, began to unravel as soon as the fraught decisions were taken on the details of unifying the protectionist agricultural policies of six different countries. In particular, the decision to fix the initial level of common cereals prices at the upper end of the national spread set an unsatisfactory reference point for other support prices; and an attempt to introduce a genuine common structural policy was rejected. At the turn of the 1970s, the CAP was clearly unbalanced and protectionist, but the Community's first fully-fledged common policy had been constructed. Il y a cinquante ans, s'est tenue à Stresa une Conférence qui pourrait être considérée comme l'évènement unique qui marque le mieux la naissance de la PAC. Bien que cinq objectifs pour l'action publique aient été inscrits dans le Traité de Rome en 1957, leur caractère imprécis et contradictoire a fait l'objet de nombreuses critiques et le Traité ne comportait que de très rares indications sur les instruments de politique à adopter. La Conférence de Stresa a permis de réaliser des progrès importants mais incomplets dans la définition du cadre de l'action publique. Intéressant à noter, il a généralement été convenu d'éviter un niveau de soutien des prix qui engendrerait des surplus excessifs de produits de base et empêcherait l'ajustement structurel. Mais ces bonnes intentions, ainsi que l'esprit "européen" positif de la Conférence, ont commencéà se dissoudre dès que des décisions problématiques furent prises sur le détail de l'uniformisation des politiques agricoles protectionnistes de six pays différents. En particulier, la décision consistant à fixer le niveau initial des prix communs des céréales à la borne supérieur du spectre des prix nationaux a constitué un point de référence peu satisfaisant pour les autres prix de soutien; et la tentative d'introduire une vraie politique commune des structures a avorté. Au tournant des années soixante dix, la PAC était nettement déséquilibrée et protectionniste, mais la première politique complètement commune de la Communautéétait en place. Vor 50 Jahren fand in Stresa eine Konferenz statt, bei welcher es sich wohl um das einzige Ereignis handelt, welches am zutreffendsten als Geburtstag der GAP betrachtet werden kann. Obgleich die politische Zielsetzung bereits 1957 in den Römischen Verträgen festgelegt worden war, standen diese wegen ihrer vagen Formulierung und Widersprüchlichkeit häufig im Kreuzfeuer der Kritik. Die Verträge enthielten nur sehr wenige konkrete Vereinbarungen im Hinblick auf die einzuführenden politischen Instrumente. Durch die Konferenz in Stresa konnten wichtige, jedoch unvollständige, Fortschritte bei der Ausarbeitung der politischen Rahmenbedingungen erzielt werden. Vor allem gab es den allgemeinen Konsens, dass es aufgrund der Preisstützung nicht zu unerwünschten Überschüssen bei Agrarprodukten und zu einer Hemmung der Strukturanpassungen kommen dürfe. Diese guten Absichten und die "europäische Gesinnung" der Konferenz schwanden jedoch, als die bedeutsamen Entscheidungen hinsichtlich der Einzelheiten für die Vereinheitlichung der protektionistischen Agrarpolitiken der sechs verschiedenen Länder getroffen wurden. Insbesondere die Entscheidung, das Anfangsniveau der gemeinsamen Preise für Getreide an der oberen Grenze der nationalen Preisspannen festzumachen, legte einen unbefriedigenden Referenzpunkt für die übrigen Stützpreise fest. Der Vorschlag, eine originär gemeinsame Strukturpolitik einzuführen, wurde abgelehnt. Um 1970 war die GAP eindeutig unausgewogen und protektionistisch; der Entwurf der ersten vollständigen gemeinsamen Politik der Gemeinschaft war jedoch abgeschlossen. [source] The relationship between fishing methods, fisheries management and the estimation of maximum sustainable yieldFISH AND FISHERIES, Issue 4 2002Mark N Maunder Abstract The allocation of effort among fishing gears is as important as controlling effort with respect to both sustainable yield and ecosystem management. Differences in age-specific vulnerability to the fishing method can modify the maximum sustainable yield (MSY) that is obtainable from a fish stock. Different gears or methods are more or less selective for the species targeted, and MSY is rarely, if ever, attainable simultaneously for all species. The different fishing methods capture different types of nontarget species. Some methods will often be more profitable than others, and different user groups will prefer different methods. In many fisheries, it is unlikely that fishing can be limited to a single gear or method, so compromises among them will be required. Global MSY is discussed as a possible reference point for fisheries management. The yellowfin tuna fishery in the eastern Pacific Ocean (EPO) shows all the above characteristics and is used to illustrate effort allocation among fishing methods. [source] A new role for MSY in single-species and ecosystem approaches to fisheries stock assessment and managementFISH AND FISHERIES, Issue 1 2001In 1977, Peter Larkin published his now-famous paper, ,An epitaph for the concept of maximum sustained yield'. Larkin criticized the concept of single-species maximum sustained yield (MSY) for many reasons, including the possibility that it may not guard against recruitment failure, and the impossibility of maximising sustainable yields for all species simultaneously. However, in recent years, there has been a fundamental change in the perception of the fishing mortality associated with MSY (FMSY) as a limit to be avoided rather than a target that can routinely be exceeded. The concept of FMSY as a limit is embodied in several United Nations Food and Agriculture Organization (FAO) agreements and guidelines, and has now been incorporated into the US Magnuson,Stevens Fishery Conservation and Management Act. As a result, the United States now requires the development of overfishing definitions based on biological reference points that treat the FMSY as a limit reference point and must also define a lower limit on biomass below which rebuilding plans with strict time horizons must be developed. This represents a major paradigm shift from the previously mandated (but often unachieved) objective to simply maintain fishing mortalities at levels below those associated with recruitment overfishing. In many cases, it requires substantial reductions in current fishing mortality levels. Therefore, the necessity of the new paradigm is continually questioned. This paper draws on examples from several fisheries, but specifically focuses on the recent US experience illustrating the practical difficulties of reducing fishing mortality to levels below those corresponding to MSY. However, several studies suggest that even more substantial reductions in fishing mortality may be necessary if ecosystem considerations, such as multispecies interactions, maintenance of biodiversity and genetic diversity, and reduction of bycatch and waste, are taken into account. The pros and cons of moving beyond single-species assessment and management are discussed. A US plan for improving stock assessments indicates that even a ,basic' objective such as ,adequate baseline monitoring of all managed species' may be extremely costly. Thus, the suggestion of Larkin (1983, 1997) that the costs of research and management should not exceed 10,20% of the landed value of the catch may preclude comprehensive ecosystem management. More importantly, neither single-species nor ecosystem-based fisheries management is likely to improve appreciably unless levels of fishing capacity are aligned with resource productivity, as is currently being promoted by FAO and several individual nations. [source] Network-magnetotelluric method and its first results in central and eastern Hokkaido, NE JapanGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 1 2001Makoto Uyeshima Summary A new field observation technique based on the magnetotelluric (MT) method has been developed to determine deep and large-scale 3-D electrical conductivity distributions in the Earth. The method is named ,Network-MT', and employs a commercial telephone network, to measure voltage differences with long dipole lengths ranging from 10 to several tens of kilometres. This observation configuration enables us to obtain the telluric field distribution with nearly continuous coverage over a target region. Response functions are estimated between the respective voltage differences and the horizontal magnetic fields at a reference point. Owing to the long electrode spacing, the observed responses are relatively free from the effects of small-scale near-surface heterogeneity with a scalelength shorter than the typical electrode spacing. Therefore, physically meaningful direct comparison between the observations and model responses is feasible even if the fine-scale features of near-surface heterogeneity are ignored. This extensively reduces the difficulty, especially in 3-D MT interpretation. The first Network-MT experiment was performed in central and eastern Hokkaido, NE Japan, in 1989. It took about five months to complete all of the measurements, and used 209 dipoles to cover the target area of 200(EW) × 200(NS) km2. The long electrode spacing enabled us to obtain the voltage differences with a high signal-to-noise ratio. For 175 dipoles, the squared multiple coherency between the voltage difference and the horizontal magnetic field at Memambetsu Geomagnetic Observatory was determined to be more than 0.9 in the period from 102 to 104 s. 193 MT impedances were computed in tensor form by linear combination of the response functions. The estimated impedances generally possessed smooth period dependence throughout the period range. No drastic spatial change was observed in the characteristics of the tensors for neighbouring sites, and some regional trend could be detected in the spatial distribution. Thus, we confirmed the merit of the Network-MT method, that its responses are little affected by small-scale near-surface structures. The regional feature of the response implied a significant influence of the coast effect, and was well correlated with the regional geological setting in Hokkaido. Conventional Groom,Bailey tensor decomposition analysis revealed that the target region is not regionally one- or two-dimensional. Therefore, we developed a 3-D forward modelling scheme specially designed for the Network-MT experiment, and tried to reproduce the Network-MT responses directly. In the 3-D model, a realistic land,sea distribution was considered. The resistivity of sea water was fixed to be 0.25 , m and, as a first trial of 3-D modelling, the resistivity of the land was assumed to be uniform and its value was determined to be 200 , m by a simple one-parameter inversion. Overall agreements between the observations and the best-fit model responses indicated the importance of the 3-D coast effect in the target region. However, there remained significant discrepancies, especially in the phase of the responses, which provide a clue to determining a regional deep 3-D structure. [source] A typology of reviews: an analysis of 14 review types and associated methodologiesHEALTH INFORMATION & LIBRARIES JOURNAL, Issue 2 2009Maria J. Grant Background and objectives:, The expansion of evidence-based practice across sectors has lead to an increasing variety of review types. However, the diversity of terminology used means that the full potential of these review types may be lost amongst a confusion of indistinct and misapplied terms. The objective of this study is to provide descriptive insight into the most common types of reviews, with illustrative examples from health and health information domains. Methods:, Following scoping searches, an examination was made of the vocabulary associated with the literature of review and synthesis (literary warrant). A simple analytical framework,Search, AppraisaL, Synthesis and Analysis (SALSA),was used to examine the main review types. Results:, Fourteen review types and associated methodologies were analysed against the SALSA framework, illustrating the inputs and processes of each review type. A description of the key characteristics is given, together with perceived strengths and weaknesses. A limited number of review types are currently utilized within the health information domain. Conclusions:, Few review types possess prescribed and explicit methodologies and many fall short of being mutually exclusive. Notwithstanding such limitations, this typology provides a valuable reference point for those commissioning, conducting, supporting or interpreting reviews, both within health information and the wider health care domain. [source] A 5-year review of teeth filled with the noninstrumentation technologyINTERNATIONAL ENDODONTIC JOURNAL, Issue 7 2009B. Suter Abstract Aim, The aim of this Case Series was to evaluate the radiographic quality of root fillings performed 5 years previously using the noninstrumentation technology (NIT)-obturation method and to assess radiographically the outcome of these root canal treatments. Methodology, Seventeen patients requiring root canal treatment participated in this study and were re-evaluated after 5 years. After instrumentation with K-Flexofiles, Calcium-Hydroxide inter-appointment dressing, re-entry and copious irrigation with NaOCl, the teeth were root filled using the NIT. Results, Immediately after obturation the root fillings were (,0.78 ± 0.11 mm) short when taking the radiographic apex as a reference point. After 60 months these values were ,0.85 ± 0.11 mm. No statistical difference was found (P > 0.05). In the periapical region, PAI rating 1 and 2 increased from 20.1% to 75.6% after 60 months. Conclusions, ,,This prospective Case Series demonstrated the performance of the NIT-obturation method in vivo. ,,Root canals filled by the reduced-pressure method using sealer combined with gutta-percha cones showed good radiographic quality. ,,Periapical healing after 5 years was comparable with conventional filling techniques. [source] In vivo determination of root canal length: a preliminary report using the Tri Auto ZX apex-locating handpieceINTERNATIONAL ENDODONTIC JOURNAL, Issue 7 2002F. Grimberg Abstract Aim The aim of this study was to assess the clinical perfomance of a cordless handpiece with a built-in apex locator , the Tri Auto ZX , designed for root canal preparation with nickel-titanium rotary files. Methodology Twenty-five human maxillary incisor and canine teeth scheduled for extraction with mature apices were selected for the study. Informed written consent was obtained from each patient before treatment. After administration of local anaesthesia, the teeth were isolated and the pulp cavities accessed. The Tri Auto ZX along with a size 15 K-file was used in its electronic apex locating function based on the manufacturer's recommendations. A periapical radiograph with the file at the electronically determined constriction was taken, the file removed and the measurement registered as the electronic length (EL). To test the auto reverse function, a size 20 ProFile .04 taper NiTi rotary instrument was mounted in the handpiece. The point for the auto apical reverse function was preset on the panel at the 0.5 mm level. After the file was introduced into the canal and reached the predetermined level, the file automatically stopped and rotated in the opposite direction. A reference point was marked and this measurement was registered as the auto reverse length (ARL). All measurements were made twice by two different investigators. Teeth were then extracted and immersed in a 20% formalin solution for 48 h. After fixation, a size 15 file was inserted into the canal to measure the actual root canal length from the same reference point obtained with the Tri Auto ZX to the apical foramen, as seen in the stereo microscope. When the file tip was visible at the anatomical end of the canal it was withdrawn 0.5 mm and this measurement was registered as the actual length (AL). All measurements were expressed in mm and the measuring accuracy was set to 0.5 mm. The significance of the mean differences between EL and ARL and between EL and AL measurements at the 5% confidence level was evaluated. Results EL measurements were coincident to ARL in all instances. EL and ARL were coincident to AL in 10 (40%) canals, in the remaining 15 canals (60%) the AL measurements were longer than EL and ARL (+0.5 mm) in 14 instances and shorter (,0.5 mm) in one case. Overall, the AL was longer than the EL or ARL, the mean difference being ,0.23 mm ± 0.32 (P < 0.05). Conclusions It was concluded that the Tri Auto ZX was useful and reliable. The Tri Auto ZX measurements protected against overpreparation. [source] Irreducibility and structural cointegrating relations: an application to the G-7 long-term interest ratesINTERNATIONAL JOURNAL OF FINANCE & ECONOMICS, Issue 2 2001Marco R. Barassi C32; C51 Abstract In this paper we examine the causal linkages between the G-7 long-term interest rates by using a new technique, which enables the researcher to analyse relations between a set of I(1) series without imposing any identification conditions based on economic theory. Specifically, we apply the so-called Extended Davidson's Methodology (EDM), which is based on the innovative concept of an irreducible cointegrating (IC) vector, defined as a subset of a cointegrating relation that does not have any cointegrated subsets. Ranking the irreducible vectors according to the criterion of minimum variance allows us to distinguish between structural and solved relations. The empirical results provide support for the hypothesis that larger, more stable economies can achieve policy objectives more successfully by accommodating rather than driving other countries' policies. It appears that the driving force is Canada, which is linked to the USA, UK and France in three out of the four fundamental relations, and which is a reference point for the US, Italian and German rates, which are not cointegrated, seem to be determined by country-specific factors. Copyright © 2001 John Wiley & Sons, Ltd. [source] Output feedback control design for station keeping of AUVs under shallow water wave disturbancesINTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 13 2009Shuyong Liu Abstract In this paper, we consider the problem of autonomous underwater vehicle (AUV) station keeping (SK) in shallow water area. During SK, an AUV is required to maintain position and orientation with respect to a fixed reference point at the sea floor. When AUV operates in shallow water, high-frequency disturbances due to waves will significantly affect the motion of the AUV. In order to derive wave disturbance information for control purposes, a nonlinear observer is first designed to estimate the shallow water wave velocities and AUV relative velocities by using position and attitude measurement. Using the observer estimates, a nonlinear output feedback controller is subsequently synthesized by applying observer backstepping technique. Global exponential stability (GES) of the proposed nonlinear observer,controller design is proved through Lyapunov stability theory. Simulation studies on a model based on an actual AUV were performed to verify the performance of the proposed nonlinear observer and output feedback controller. Copyright © 2008 John Wiley & Sons, Ltd. [source] Protecting the Old in a Young Economy: Old Age Insurance in the West Bank and Gaza StripINTERNATIONAL SOCIAL SECURITY REVIEW, Issue 3 2000Markus Loewe Taking the West Bank and Gaza Strip as a reference point, this paper looks at social protection in developing economies, which are beset by economic stagnation, widespread poverty and unemployment. If the main breadwinner dies, is unable to work or is an older person, these factors are prime causes of absolute poverty. This is hardly surprising, since private and public systems of social security are totally inadequate in this area in particular. Current thinking on social security suggests that what is needed is the rapid introduction of a comprehensive system of retirement provision, comprising a mandatory capital-funded insurance component, with defined contributions, administered on a decentralized basis; and a state-administered pay-as-you-go basic insurance component with lump-sum transfers to safeguard the poorest. A system of this kind works to prevent poverty in old age by redistributing funds from some individuals to others and ensuring an income for life, and it represents a compromise between a fair return on what people have contributed and a fair distribution over society as a whole. It is thus a major force for stability in society. [source] The critical-size supraalveolar peri-implant defect model: characteristics and useJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 11 2006Ulf M. E. Wikesjö Abstract Objective: Novel implant technologies and reconstructive therapies for alveolar augmentation require pre-clinical evaluation to estimate their biologic potential, efficacy, and safety before clinical application. The objective of this report is to present characteristics and use of the critical-size, supraalveolar, peri-implant defect model. Methods: Bilateral extraction of the mandibular premolars was performed in 12 Hound Labrador mongrel dogs following horizontal surgical cut-down of the alveolar ridge approximating 6 mm. Each jaw quadrant received three custom-produced TiUniteÔ, ,4.0 × 10 mm threaded implants placed into osteotomies prepared into the extraction sites of the third and fourth premolars. The implants exhibited a reference notch 5 mm from the implant platform to facilitate surgical placement leaving 5 mm of the implant in a supraalveolar position, and to serve as a reference point in the radiographic, histologic and histometric analysis. The implants were submerged under the mucoperiosteal flaps for primary intention healing. Fluorescent bone markers were administered at weeks 3 and 4 post-surgery, and pre-euthanasia. The animals were euthanized following an 8-week healing interval when block biopsies were collected for analysis. Results: Healing was generally uneventful. The radiographic and histometric evaluations demonstrate the limited osteogenic potential of this defect model. Whereas lingual peri-implant sites exhibited a mean (±SE) bone gain of 0.4±0.1 mm, resorption of the buccal crestal plate resulted in a mean bone loss of 0.4±0.2 mm for an overall osteogenic potential following sham-surgery averaging 0.0±0.1 mm. Overall bone density and bone,implant contact in the contiguous resident bone averaged 79.1±1.1% and 76.9±2.3%, respectively. Conclusion: The results suggest that the critical-size, supraalveolar, peri-implant defect model appears a rigorous tool in the evaluation of candidate technologies for alveolar reconstruction and osseointegration of endosseous oral implants. Limited innate osteogenic potential allows critical evaluation of osteogenic, osteoconductive, or osteoinductive technologies in a challenging clinical setting. [source] Spectres of Transnationalism: Changing Terrains of Sociology of LawJOURNAL OF LAW AND SOCIETY, Issue 4 2009Roger Cotterrell The growth of ,legal transnationalism', that is, the reach of law across nation-state borders and the impact of external political and legal pressures on nation-state law , undermines the main foundations of sociology of law. Modern sociology of law has assumed an ,instrumentalist' view of law as an agency of the modern directive state, but now it has to adjust to the state's increasingly complex regulatory conditions. The kind of convergence theory that underpins analysis of much legal transnationalism is inadequate for socio-legal theory, and old ideas of ,law' and ,society' as the foci of sociology of law are no longer appropriate. Socio-legal theory should treat law as a continuum of unstable, competing authority claims. Instead of taking ,society' as its reference point, it should conceptualize the contrasting types of regulatory needs of the networks of community (often not confined by nation-state boundaries) that legal transnationalism addresses. [source] A reference point approach to coalition gamesJOURNAL OF MULTI CRITERIA DECISION ANALYSIS, Issue 2-3 2005*Article first published online: 5 JUL 200, Andrzej P. Wierzbicki Abstract One of the basic concepts of the theory of coalition games is the core of the game, together with its various extensions. However, the core is usually a set, a subset of Pareto set. Therefore, all problems of vector optimization and multiple criteria decision support arise when selecting points within a core. One of interactive decision support approaches is the use of reference points and the maximization of corresponding achievement functions. The paper proposes some ways of defining and using reference points that result in equitable allocations. One way of defining such reference points is to use known solutions of coalition games, such as Shapley value or Banzhaf value. Another way of defining such reference points might be an extension of Raiffa,Kalai,Smorodinski solution to coalition games, proposed in the paper. The properties of resulting equitable allocations in the core of the game are examined. The possibility of empty core and allocations in an extended core is also examined and the concept of maximal robustness point is introduced; this point might also be used as a reference point. Possible applications of this extension of the theory of coalition games concern business negotiations. An illustrative example of negotiating a cooperative merger of three or four high-tech firms is given. The basic conclusion from the analysis and the examples presented in the paper is that axiomatic solutions of coalition games, e.g. Shapley and Banzhaf values, should be considered as reference points for vector optimization and multicriteria decision support rather than as normative solutions. Moreover, beside these axiomatic solutions there are several other possible definitions of reference points, such as the Raiffa solution or the maximal robustness point, that might be preferred by negotiators when solving practical coalition games. This has been confirmed by simulated gaming exercises performed by students under a strong motivation to treat simulated game seriously. Copyright © 2006 John Wiley & Sons, Ltd. [source] Egalitarian consultation meetings: an alternative to received wisdom about clinical supervision in psychiatric nursing practiceJOURNAL OF PSYCHIATRIC & MENTAL HEALTH NURSING, Issue 6 2000C. Stevenson RMN BA (HONS) PhD Clinical supervision (CS) has become a watchword for psychiatric nursing. Yet, there are contradictions and controversies in academic and professional discourse in relation to the nature of CS, both structure and process, its effectiveness and how this is ascertained, the preparation of supervisor and supervisee, and the quality of the supervisory relationship. The perception of such discord encouraged the authors of this paper to step outside the debate and enact a different kind of CS, which came to be known as egalitarian consultation (EC). Egalitarian consultation meetings (ECMs) were established with the postmodern turn in psychiatric nursing as a reference point. A space was created in which participants could construct their particular version of CS. The authors and six G-grade community psychiatric nurses engaged with each other for six videotaped meetings. The data from the recordings were analysed using a hermeneutic grounded theory approach (Strauss & Corbin 1994), in keeping with the style of the research, which combined the roles of researcher and practitioner for the authors. The aim was to produce local knowledge of CS. The ECMs were characterized by a sense of freedom in relation to existing rules about hierarchy and truth. The participants, each as expert in her/his own case world, produced engrossing narratives about and for practice. The group developed a cohesiveness based in closeness and this encouraged radical talk and action , a questioning of practice systems. However, for some group members, radical equated to dangerous in terms of the watchful organization and a return to ,real' work (case supervision) was observed. Innovation in relation to CS may benefit from a change in institutional culture. [source] The interdental gingiva, a visible guide for placement of mini-implantsORTHODONTICS & CRANIOFACIAL RESEARCH, Issue 1 2009YS Chun Structured Abstract Authors,,, Chun YS, Lee SK, Wikesjö UME, Lim WH Objectives,,, To determine whether the tip of the interdental gingiva can serve as a visible guide for placement of mini-implants. Setting and Sample population,,, Computer tomography (CT) images from 15 males and 15 females (mean age 27 years, range: 23,35 years) were used to evaluate the distance from the tip of the interdental gingiva to the alveolar crest from the central incisor to the 1st molar. The distance from a reference point to the tip of interdental gingiva was recorded from study models using a caliper. The distance between the reference point and the alveolar crest was recorded using CT and added to the model recordings thus providing the distance from the tip of interdental gingiva to the alveolar crest for the various interdental sites. Two-way anova and Student,Newman,Keuls test for multiple comparisons were used for the statistical analysis. Results,,, There was no significant difference in the distance from the tip of interdental gingiva to the alveolar crest between maxilla and mandible. The distance between the tip of interdental gingiva and the alveolar crest at the central/lateral incisors was the shortest compared with that of other sites. There was also a statistically significant difference between the male and female groups except for the maxillary 2nd premolar/1st molar interradicular site. Conclusion,,, The tip of interdental gingiva appears a reasonable visual guide for the placement of mini-implants for orthodontic anchorage. [source] The Incidence of Spontaneous Epidural Abscess in Olmsted County from 1990 Through 2000: A Rare Cause of Spinal PainPAIN MEDICINE, Issue 4 2007Anne E. Ptaszynski MD ABSTRACT Objective., The primary objective of this study is to determine the population-based incidence of spontaneous epidural abscess. The secondary objective is to characterize the clinical course of patients with this rare infectious disease. Design., The records-linkage system of the Rochester Epidemiology Project was used to identify incident cases of spontaneous epidural abscess in residents of Olmsted County, Minnesota, USA, from 1990 through 2000. Setting., Tertiary referral medical center. Patients., All patients were residents of Olmsted County and had spontaneous epidural abscesses that were radiographically or surgically confirmed. Results., Eight patients, including six women, were identified and the mean age was 56 years (range, 40,80). The incidence of epidural abscess was 0.88 cases per 100,000 person-years (95% confidence interval, 0.27,1.48). The median time from symptom onset to diagnosis was 18 days (interquartile range, 4,30 days). Six patients presented with spinal pain and one presented with focal neurological deficits. Risk factors were identified in all patients, including concomitant infections, diabetes mellitus, immunosuppression, and intravenous substance abuse. Staphylococcus aureus was cultured in six patients and streptococcal species were cultured in two patients. Three patients were treated surgically and five received medical treatment. One patient treated surgically and one patient treated medically had residual neurological deficits. One patient, who was immunosuppressed and received medical treatment died of pneumonia. Conclusions., This is the first published report of the population-based incidence of spontaneous epidural abscess. These findings could serve as a reference point for further epidemiological research related to this uncommon infection. [source] The Implications of Prospect Theory for Human Nature and ValuesPOLITICAL PSYCHOLOGY, Issue 2 2004Robert Jervis Central to prospect theory are far-reaching claims about what people fear and what gratifies them. Subjective well-being is a topic that social science has been reluctant to discuss in recent years, but it is central to much of our lives. A loss inflicts more harm than a comparable gain produces pleasure; this fact and the related endowment effect are important parts of our psychological makeup. The importance of change rather than absolute value position, and the related significance of the reference point and how it can be altered, can be seen as integral to human nature. [source] An empirical investigation of framing effects in negotiations: A study of single-family home salesPSYCHOLOGY & MARKETING, Issue 5 2008Carl L. Witte This paper integrates Prospect Theory and the concept of framing in a study of consumer negotiated pricing in a real estate context. Building on previously conducted experimental designs, a field survey indicated that home sellers using sales price as a reference point display greater willingness to make concessions than those who use equity as their reference point. Further, the third-party influence of the realtor was shown to alter Prospect Theory predictions so that even equity-based sellers became concessionary. © 2008 Wiley Periodicals, Inc. [source] The interaction of message frames and reference points in prosocial persuasive appealsPSYCHOLOGY & MARKETING, Issue 11 2007Peggy Sue LorozArticle first published online: 9 OCT 200 This research seeks to reconcile inconsistent results obtained in prior framing research in prosocial persuasion contexts by proposing that the reference point (self or self-other) invoked in a persuasive appeal moderates the impact of a particular message frame (positive or negative) on attitudes and behavioral intentions. Two experiments were conducted in which frame and reference point were manipulated in persuasive messages promoting either recycling or prevention of HPV, a sexually transmitted disease. The results indicate that in persuasive social contexts, negative frames may be most persuasive with self-referencing appeals while positive frames work best when benefits to self as well as others are emphasized. This suggests that developers of prosocial communications should be cognizant of both the message frame and the reference point invoked in these messages in order to have maximum persuasion impact. © 2007 Wiley Periodicals, Inc. [source] Kinematics and energetics of nut-cracking in wild capuchin monkeys (Cebus libidinosus) in Piauí, BrazilAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2009Q. Liu Abstract Wild bearded capuchins (Cebus libidinosus, quadrupedal, medium-sized monkeys) crack nuts using large stones. We examined the kinematics and energetics of the nut-cracking action of two adult males and two adult females. From a bipedal stance, the monkeys raised a heavy hammer stone (1.46 and 1.32 kg, from 33 to 77% of their body weight) to an average height of 0.33 m, 60% of body length. Then, they rapidly lowered the stone by flexing the lower extremities and the trunk until the stone contacted the nut. A hit consisting of an upward phase and a downward phase averaged 0.74 s in duration. The upward phase lasted 69% of hit duration. All subjects added discernable energy to the stone in the downward phase. The monkeys exhibited individualized kinematic strategies, similar to those of human weight lifters. Capuchins illustrate that human-like bipedal stance and large body size are unnecessary to break tough objects from a bipedal position. The phenomenon of bipedal nut-cracking by capuchins provides a new comparative reference point for discussions of percussive tool use and bipedality in primates. Am J Phys Anthropol 2009. © 2008 Wiley-Liss, Inc. [source] Reserve Prices in Auctions as Reference Points,THE ECONOMIC JOURNAL, Issue 520 2007Stephanie Rosenkranz We consider second-price and first-price auctions in the symmetric independent private values framework. We modify the standard model by the assumption that the bidders have reference-based utility, where a publicly announced reserve price has some influence on the reference point. It turns out that the seller's optimal reserve price increases with the number of bidders. Also in contrast to the standard model, we find that secret reserve prices can outperform public reserve prices, and that setting the optimal reserve price can be more valuable for the seller than attracting additional bidders. [source] The release of genetically modified crops into the environmentTHE PLANT JOURNAL, Issue 1 2003Part II. Summary Despite numerous future promises, there is a multitude of concerns about the impact of GM crops on the environment. Key issues in the environmental assessment of GM crops are putative invasiveness, vertical or horizontal gene flow, other ecological impacts, effects on biodiversity and the impact of presence of GM material in other products. These are all highly interdisciplinary and complex issues. A crucial component for a proper assessment is defining the appropriate baseline for comparison and decision. For GM crops, the best and most appropriately defined reference point is the impact of plants developed by traditional breeding. The latter is an integral and accepted part of agriculture. In many instances, the putative impacts identified for GM crops are very similar to the impacts of new cultivars derived from traditional breeding. When assessing GM crops relative to existing cultivars, the increased knowledge base underpinning the development of GM crops will provide greater confidence in the assurances plant science can give on the risks of releasing such crops. [source] Effort and Aspirations in Tax Evasion: Experimental EvidenceAPPLIED PSYCHOLOGY, Issue 3 2009Erich Kirchler Is the effort exerted to earn taxable income considered in compliance decisions? And if so, is hard-earned income or easy money more likely to be concealed from authorities? While economic theory postulates that prior costs should not affect present decisions, psychological research shows that prior investments of money, time, or effort do matter. Findings from previous studies on the impact of effort on abstract decision tasks suggest two contradictory predictions for the context of tax compliance decisions: Either taxable income earned by high effort is subjectively of higher value, and therefore more likely to be evaded, or investments of effort cause a shift of the reference point through the establishment of an aspiration level, resulting in honest declaration of income. Two experiments were conducted to test these predictions. In a business simulation, taxable income was obtained by different levels of effort and consequently had to be reported to authorities. Results show that tax evasion was more pronounced in low-effort conditions. This suggests that effort changes the reference point rather than the slope, and provides evidence that in tax compliance decisions aspiration levels serve as reference points. Implications for tax audits are discussed. L'effort déployé pour obtenir des revenus imposables est-il pris en compte dans les décisions qui en découlent? Et si c'est le cas, est-ce l'argent facile ou les revenus durement gagnés qui présentent une plus forte probabilité d'être soustraits au fisc? Alors que la théorie économique postule que le coût antérieur n'a pas de retombées sur les décisions présentes, les recherches de psychologie montrent que les investissements passés en argent, temps ou effort ont leur importance. Des travaux sur l'impact de l'effort sur des tâches de décision abstraite débouchent sur deux prédictions contradictoires en ce qui concerne les décisions relatives à l'impôt: ou le revenu imposable obtenu à la suite d'un effort substantiel est subjectivement fortement valorisé et a de fortes chances d'être camouflé, ou l'effort investi provoque un changement de référence à travers l'instauration d'un niveau d'aspiration, ce qui a pour conséquence une déclaration honnête des revenus. On a réalisé deux expériences pour mettre à l'épreuve ces prédictions. Dans une simulation commerciale, le revenu imposable a été obtenu suite à différents niveaux d'effort et devait être portéà la connaissance du fisc. Les résultats montrent que l'évasion fiscale était plus accentuée dans les conditions où l'effort était modeste. Il faut en conclure que l'effort entraîne une mutation du système de référence plutôt qu'une simple modification de niveau et que dans les décisions relatives à l'impôt les niveaux d'aspiration servent de point de référence. On réfléchit aux leçons à en tirer pour le contrôle fiscal. [source] A new class of coherent risk measures based on p -norms and their applicationsAPPLIED STOCHASTIC MODELS IN BUSINESS AND INDUSTRY, Issue 1 2007Zhiping Chen Abstract To exercise better control on the lower tail of the loss distribution and to easily describe the investor's risk attitude, a new class of coherent risk measures is proposed in this paper by taking the minimization of p -norms of lower losses with respect to some reference point. We demonstrate that the new risk measure has satisfactory mathematical properties such as convexity, continuity with respect to parameters included in its definition, the relations between two new risk measures are also examined. The application of the new risk measures for optimal portfolio selection is illustrated by using trade data from the Chinese stock markets. Empirical results not only support our theoretical conclusions, but also show the practicability of the portfolio selection model with our new risk measures. Copyright © 2006 John Wiley & Sons, Ltd. [source] Equivocal Masculinity: New York Dada in the context of World War IART HISTORY, Issue 2 2002Amelia Jones This essay explores a cluster of works by the group of artists retroactively labelled `New York Dada' in light of the pressures exerted on masculine subjectivity during the WWI period. While the war has, for obvious reasons, been a key reference point for studies of European Dada, it has never been acknowledged (beyond passing references) as a context for the New York group (in particular, for the work of the key figures Man Ray, Francis Picabia and Marcel Duchamp). Failing to attend to the Great War as a crucial historical pressure on the group simply accepts at face value these artists' own desire to escape the war (in the case of Picabia, Duchamp, Jean Crotti and others, by leaving Europe and coming to New York). This essay, in contrast, insists upon attending to the effects of the war environment , with its heated discourses of heroism and patriotic nationalism , on the New York Dada group (which, after all, would not have existed had these artists not left Europe for New York because of the war). Examining the relationship of each of the key NewYork Dada figures to the war, it explores a selection of their works in relation to these experiences. Ultimately, I argue that the artists' non-combatant masculinity, compromised in the face of dominant discourses of militarized masculinity, is eerily and disconcertingly echoed by the predominance of shadows, gaps and absences in their visual art works. [source] On QoS mechanism profiling in MPLS-TP transport networksBELL LABS TECHNICAL JOURNAL, Issue 4 2010Christian Addeo In the context of packet management in optical transport networks, quality of service (QoS) is playing an important role to achieve the right levels of bandwidth, latency, and general treatment for the different services carried over the network. The scope of this paper is to describe quality of service functionalities in the context of a packet transport network. This paper refers to the definition and implementation of the quality of service model in a packet transport network node, describing how this information is carried over a packet transport network. The Alcatel-Lucent 1850 Transport Service Switch (TSS) platform serves as our reference point for a packet transport node. We also include a description of classification, policing, marking, and, in particular, hierarchical scheduling and shaping. © 2010 Alcatel-Lucent. [source] |