973 resultados para minimum cost
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Field-programmable gate arrays are ideal hosts to custom accelerators for signal, image, and data processing but de- mand manual register transfer level design if high performance and low cost are desired. High-level synthesis reduces this design burden but requires manual design of complex on-chip and off-chip memory architectures, a major limitation in applications such as video processing. This paper presents an approach to resolve this shortcoming. A constructive process is described that can derive such accelerators, including on- and off-chip memory storage from a C description such that a user-defined throughput constraint is met. By employing a novel statement-oriented approach, dataflow intermediate models are derived and used to support simple ap- proaches for on-/off-chip buffer partitioning, derivation of custom on-chip memory hierarchies and architecture transformation to ensure user-defined throughput constraints are met with minimum cost. When applied to accelerators for full search motion estima- tion, matrix multiplication, Sobel edge detection, and fast Fourier transform, it is shown how real-time performance up to an order of magnitude in advance of existing commercial HLS tools is enabled whilst including all requisite memory infrastructure. Further, op- timizations are presented that reduce the on-chip buffer capacity and physical resource cost by up to 96% and 75%, respectively, whilst maintaining real-time performance.
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Introdução: Em Portugal a realidade actual, clínica e financeira do exercício da Medicina Dentária é bem distinta da do final do séc. XX devido à pletora de Médicos Dentistas e à baixa de honorários por acto Médico registada nos últimos anos. Objectivos: Este trabalho teve como objectivo perceber um pouco sobre os detalhes a ter em consideração aquando da abertura de uma clínica centrada na realização de tratamentos na área da Endodontia, e como publicitá-la de forma legal e apelativa. Pretende-se depois também estimar o custo mínimo para a realização de tratamentos Endodonticos com diferentes equipamentos e comparar a eficácia entre tratamentos usando ferramentas diferentes. Materiais e Métodos: Foram usadas como fontes de pesquisa para o presente trabalho bases de dados como a PubMed, B-On e Cochrane Library. Foi também usado o Google. Para pesquisa no PubMed foram usados vários descritores MeSH, como “Commerce”, “Dentistry”, “Endodontics”, “Management” e “Marketing”. Foram também usadas diversas palavras-chave no PubMed e nos outros motores de pesquisa, como “Anesthesia”, “Dental Office”, “Files”, “Irrigation”, “Magnification”, “Microscope”, “Obturation Systems” e “Rotatory Systems”. As pesquisas foram filtradas para serem apresentados apenas resultados entre 2011 e 2016, sendo este filtro retirado só quando não eram encontrados resultados satisfatórios ou relevantes para os temas discutidos no trabalho. Foram obtidos 3927 artigos e seleccionados 24. A inclusão destes artigos foi feita tendo em conta as suas fontes bibliográficas e a qualidade dos estudos a que se reportavam. Foram excluídos artigos que se reportavam a estudos muito antigos ou a tecnologias ultrapassadas, como sistemas de limas antigos. Conclusões: As novas tecnologias usadas para tratamento Endodontico, apesar de dispendiosas, melhoram muito o atendimento ao paciente.
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This thesis presents approximation algorithms for some NP-Hard combinatorial optimization problems on graphs and networks; in particular, we study problems related to Network Design. Under the widely-believed complexity-theoretic assumption that P is not equal to NP, there are no efficient (i.e., polynomial-time) algorithms that solve these problems exactly. Hence, if one desires efficient algorithms for such problems, it is necessary to consider approximate solutions: An approximation algorithm for an NP-Hard problem is a polynomial time algorithm which, for any instance of the problem, finds a solution whose value is guaranteed to be within a multiplicative factor of the value of an optimal solution to that instance. We attempt to design algorithms for which this factor, referred to as the approximation ratio of the algorithm, is as small as possible. The field of Network Design comprises a large class of problems that deal with constructing networks of low cost and/or high capacity, routing data through existing networks, and many related issues. In this thesis, we focus chiefly on designing fault-tolerant networks. Two vertices u,v in a network are said to be k-edge-connected if deleting any set of k − 1 edges leaves u and v connected; similarly, they are k-vertex connected if deleting any set of k − 1 other vertices or edges leaves u and v connected. We focus on building networks that are highly connected, meaning that even if a small number of edges and nodes fail, the remaining nodes will still be able to communicate. A brief description of some of our results is given below. We study the problem of building 2-vertex-connected networks that are large and have low cost. Given an n-node graph with costs on its edges and any integer k, we give an O(log n log k) approximation for the problem of finding a minimum-cost 2-vertex-connected subgraph containing at least k nodes. We also give an algorithm of similar approximation ratio for maximizing the number of nodes in a 2-vertex-connected subgraph subject to a budget constraint on the total cost of its edges. Our algorithms are based on a pruning process that, given a 2-vertex-connected graph, finds a 2-vertex-connected subgraph of any desired size and of density comparable to the input graph, where the density of a graph is the ratio of its cost to the number of vertices it contains. This pruning algorithm is simple and efficient, and is likely to find additional applications. Recent breakthroughs on vertex-connectivity have made use of algorithms for element-connectivity problems. We develop an algorithm that, given a graph with some vertices marked as terminals, significantly simplifies the graph while preserving the pairwise element-connectivity of all terminals; in fact, the resulting graph is bipartite. We believe that our simplification/reduction algorithm will be a useful tool in many settings. We illustrate its applicability by giving algorithms to find many trees that each span a given terminal set, while being disjoint on edges and non-terminal vertices; such problems have applications in VLSI design and other areas. We also use this reduction algorithm to analyze simple algorithms for single-sink network design problems with high vertex-connectivity requirements; we give an O(k log n)-approximation for the problem of k-connecting a given set of terminals to a common sink. We study similar problems in which different types of links, of varying capacities and costs, can be used to connect nodes; assuming there are economies of scale, we give algorithms to construct low-cost networks with sufficient capacity or bandwidth to simultaneously support flow from each terminal to the common sink along many vertex-disjoint paths. We further investigate capacitated network design, where edges may have arbitrary costs and capacities. Given a connectivity requirement R_uv for each pair of vertices u,v, the goal is to find a low-cost network which, for each uv, can support a flow of R_uv units of traffic between u and v. We study several special cases of this problem, giving both algorithmic and hardness results. In addition to Network Design, we consider certain Traveling Salesperson-like problems, where the goal is to find short walks that visit many distinct vertices. We give a (2 + epsilon)-approximation for Orienteering in undirected graphs, achieving the best known approximation ratio, and the first approximation algorithm for Orienteering in directed graphs. We also give improved algorithms for Orienteering with time windows, in which vertices must be visited between specified release times and deadlines, and other related problems. These problems are motivated by applications in the fields of vehicle routing, delivery and transportation of goods, and robot path planning.
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Dissertação de Mestrado para a obtenção de grau de Mestre em Engenharia Eletrotécnica Ramo de Automação e Eletrónica Industrial
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[en] It is known that most of the problems applied in the real life present uncertainty. In the rst part of the dissertation, basic concepts and properties of the Stochastic Programming have been introduced to the reader, also known as Optimization under Uncertainty. Moreover, since stochastic programs are complex to compute, we have presented some other models such as wait-and-wee, expected value and the expected result of using expected value. The expected value of perfect information and the value of stochastic solution measures quantify how worthy the Stochastic Programming is, with respect to the other models. In the second part, it has been designed and implemented with the modeller GAMS and the optimizer CPLEX an application that optimizes the distribution of non-perishable products, guaranteeing some nutritional requirements with minimum cost. It has been developed within Hazia project, managed by Sortarazi association and associated with Food Bank of Biscay and Basic Social Services of several districts of Biscay.
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In this dissertation, we apply mathematical programming techniques (i.e., integer programming and polyhedral combinatorics) to develop exact approaches for influence maximization on social networks. We study four combinatorial optimization problems that deal with maximizing influence at minimum cost over a social network. To our knowl- edge, all previous work to date involving influence maximization problems has focused on heuristics and approximation. We start with the following viral marketing problem that has attracted a significant amount of interest from the computer science literature. Given a social network, find a target set of customers to seed with a product. Then, a cascade will be caused by these initial adopters and other people start to adopt this product due to the influence they re- ceive from earlier adopters. The idea is to find the minimum cost that results in the entire network adopting the product. We first study a problem called the Weighted Target Set Selection (WTSS) Prob- lem. In the WTSS problem, the diffusion can take place over as many time periods as needed and a free product is given out to the individuals in the target set. Restricting the number of time periods that the diffusion takes place over to be one, we obtain a problem called the Positive Influence Dominating Set (PIDS) problem. Next, incorporating partial incentives, we consider a problem called the Least Cost Influence Problem (LCIP). The fourth problem studied is the One Time Period Least Cost Influence Problem (1TPLCIP) which is identical to the LCIP except that we restrict the number of time periods that the diffusion takes place over to be one. We apply a common research paradigm to each of these four problems. First, we work on special graphs: trees and cycles. Based on the insights we obtain from special graphs, we develop efficient methods for general graphs. On trees, first, we propose a polynomial time algorithm. More importantly, we present a tight and compact extended formulation. We also project the extended formulation onto the space of the natural vari- ables that gives the polytope on trees. Next, building upon the result for trees---we derive the polytope on cycles for the WTSS problem; as well as a polynomial time algorithm on cycles. This leads to our contribution on general graphs. For the WTSS problem and the LCIP, using the observation that the influence propagation network must be a directed acyclic graph (DAG), the strong formulation for trees can be embedded into a formulation on general graphs. We use this to design and implement a branch-and-cut approach for the WTSS problem and the LCIP. In our computational study, we are able to obtain high quality solutions for random graph instances with up to 10,000 nodes and 20,000 edges (40,000 arcs) within a reasonable amount of time.
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Mestrado em Gestão e Estratégia Industrial
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To tackle the challenges at circuit level and system level VLSI and embedded system design, this dissertation proposes various novel algorithms to explore the efficient solutions. At the circuit level, a new reliability-driven minimum cost Steiner routing and layer assignment scheme is proposed, and the first transceiver insertion algorithmic framework for the optical interconnect is proposed. At the system level, a reliability-driven task scheduling scheme for multiprocessor real-time embedded systems, which optimizes system energy consumption under stochastic fault occurrences, is proposed. The embedded system design is also widely used in the smart home area for improving health, wellbeing and quality of life. The proposed scheduling scheme for multiprocessor embedded systems is hence extended to handle the energy consumption scheduling issues for smart homes. The extended scheme can arrange the household appliances for operation to minimize monetary expense of a customer based on the time-varying pricing model.
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n decentralised rural electrification through solar home systems, private companies and promoting institutions are faced with the problem of deploying maintenance structures to operate and guarantee the service of the solar systems for long periods (ten years or more). The problems linked to decentralisation, such as the dispersion of dwellings, difficult access and maintenance needs, makes it an arduous task. This paper proposes an innovative design tool created ad hoc for photovoltaic rural electrification based on a real photovoltaic rural electrification program in Morocco as a special case study. The tool is developed from a mathematical model comprising a set of decision variables (location, transport, etc.) that must meet certain constraints and whose optimisation criterion is the minimum cost of the operation and maintenance activity assuming an established quality of service. The main output of the model is the overall cost of the maintenance structure. The best location for the local maintenance headquarters and warehouses in a given region is established, as are the number of maintenance technicians and vehicles required.
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This paper examines the impact on old age poverty and the fiscal cost of universal minimum oldage pensions in Latin America using recent household survey data for 18 countries. Alleviatingold age poverty requires different approach from other age groups and a minimum pension islikely to be the only alternative available. First we measure old age poverty rates for all countries.Second we discuss the design of minimum pensions schemes, means-tested or not, as wellas the disincentive effects that they are expected to have on the economic and social behavior ofhouseholds including labor supply, saving and family solidarity. Third we use the household surveysto simulate the fiscal cost and the impact on poverty rates of alternative minimum pensionschemes in the 18 countries. We show that a universal minimum pension would substantiallyreduce poverty among the elderly except in Argentina, Brazil, Chile and Uruguay where minimumpension systems already exist and poverty rates are low. Such schemes have much tobe commended in terms of incentives, spillover effects and administrative simplicity but have ahigh fiscal cost. The latter is a function of the age at which benefits are awarded, the prevailinglongevity, the generosity of benefits, the efficacy of means testing, and naturally the fiscal capacityof the country.
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"EPA-560/4-81-002."
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A good diet and adequate food supply is central to promoting health and wellbeing. A poor quality diet is associated with higher rates of chronic diseases such as type 2 diabetes, obesity, cardiovascular disease and certain cancers. Social and economic conditions impact on diet quality which in turn contributes to health inequalities. This relationship is recognised and addressed at a policy level in NI through the Fitter Future for all framework(1). Access to a healthy diet requires transport, money and skills such as budgeting and food preparation. Food is the most flexible aspect of the household budget due to the fact the consumers can meet hunger and calorie needs on cheaper, nutritionally-poor foods.
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A Minimum Essential Standard of Living (MESL) is derived from a negotiated consensus on what people believe is a minimum standard. It is a standard of living that meets an individual’s or a household’s physical, psychological and social needs. This is calculated by identifying the goods and services required by different household types in order to meet their needs. While an MESL is based on needs, not wants, it is a standard of living below which nobody should be expected to live. This report focuses on food, one of the 16 elements of the Minimum Essential Standard of Living (MESL) data. It is based on a methodology called Consensual Budget Standards (CBS). The report is presented in the context of increasing concerns about the issue of food poverty in the Republic of Ireland (ROI) and an increase in the number of people reporting that they do not have enough money to buy food. Recent data from The Organisation for Economic Co-operation and Development (OECD) have shown that the number of people believing they cannot afford food doubled from 4.2% in 2008 to 9% in 2014. Data from Eurostat show that in 2013, food and non-alcoholic beverage prices in Ireland were 17% higher than the EU average. Moreover, research by Carney and Maitre, using data from the Survey on Income and Living Conditions (SILC), found that one in ten people are living in food poverty in Ireland. Food poverty is defined as the inability to have an adequate and nutritious diet due to issues of affordability and access to food. This has related effects on health, culture and social participation. The 2013 data from the Survey on Income and Living Conditions (SILC) show that 1.4 million people, almost 31% of the population, suffer from deprivation. This means that they are unable to afford two items from a list of 11 very basic items (of which one is not being able to eat a meal with meat, chicken, fish or a vegetarian equivalent every second day). The highest levels of deprivation are experienced by lone parents (63%), unemployed people (55%) and people not at work because of illness or disability (53%). The experience of the Vincentian Partnership for Social Justice (VPSJ) is that expenditure on food tends to be one of the least important considerations when households are dealing with competing demands on an inadequate income. A Minimum Essential Standard of Living (MESL) is derived from a negotiated consensus on what people believe is a minimum standard. It is a standard of living that meets an individual’s or a household’s physical, psychological and social needs. This is calculated by identifying the goods and services required by different household types in order to meet their needs. While an MESL is based on needs, not wants, it is a standard of living below which nobody should be expected to live. This report focuses on food, one of the 16 elements of the Minimum Essential Standard of Living (MESL) data. It is based on a methodology called Consensual Budget Standards (CBS). The report is presented in the context of increasing concerns about the issue of food poverty in the Republic of Ireland (ROI) and an increase in the number of people reporting that they do not have enough money to buy food. Recent data from The Organisation for Economic Co-operation and Development (OECD) have shown that the number of people believing they cannot afford food doubled from 4.2% in 2008 to 9% in 2014. Data from Eurostat show that in 2013, food and non-alcoholic beverage prices in Ireland were 17% higher than the EU average. Moreover, research by Carney and Maitre, using data from the Survey on Income and Living Conditions (SILC), found that one in ten people are living in food poverty in Ireland. Food poverty is defined as the inability to have an adequate and nutritious diet due to issues of affordability and access to food. This has related effects on health, culture and social participation. The 2013 data from the Survey on Income and Living Conditions (SILC) show that 1.4 million people, almost 31% of the population, suffer from deprivation. This means that they are unable to afford two items from a list of 11 very basic items (of which one is not being able to eat a meal with meat, chicken, fish or a vegetarian equivalent every second day). The highest levels of deprivation are experienced by lone parents (63%), unemployed people (55%) and people not at work because of illness or disability (53%). The experience of the Vincentian Partnership for Social Justice (VPSJ) is that expenditure on food tends to be one of the least important considerations when households are dealing with competing demands on an inadequate income. - See more at: http://www.safefood.eu/Publications/Research-reports/The-cost-of-a-healthy-food-basket.aspx#sthash.RiBpj5no.dpuf A Minimum Essential Standard of Living (MESL) is derived from a negotiated consensus on what people believe is a minimum standard. It is a standard of living that meets an individual’s or a household’s physical, psychological and social needs. This is calculated by identifying the goods and services required by different household types in order to meet their needs. While an MESL is based on needs, not wants, it is a standard of living below which nobody should be expected to live. This report focuses on food, one of the 16 elements of the Minimum Essential Standard of Living (MESL) data. It is based on a methodology called Consensual Budget Standards (CBS). The report is presented in the context of increasing concerns about the issue of food poverty in the Republic of Ireland (ROI) and an increase in the number of people reporting that they do not have enough money to buy food. Recent data from The Organisation for Economic Co-operation and Development (OECD) have shown that the number of people believing they cannot afford food doubled from 4.2% in 2008 to 9% in 2014. Data from Eurostat show that in 2013, food and non-alcoholic beverage prices in Ireland were 17% higher than the EU average. Moreover, research by Carney and Maitre, using data from the Survey on Income and Living Conditions (SILC), found that one in ten people are living in food poverty in Ireland. Food poverty is defined as the inability to have an adequate and nutritious diet due to issues of affordability and access to food. This has related effects on health, culture and social participation. The 2013 data from the Survey on Income and Living Conditions (SILC) show that 1.4 million people, almost 31% of the population, suffer from deprivation. This means that they are unable to afford two items from a list of 11 very basic items (of which one is not being able to eat a meal with meat, chicken, fish or a vegetarian equivalent every second day). The highest levels of deprivation are experienced by lone parents (63%), unemployed people (55%) and people not at work because of illness or disability (53%). The experience of the Vincentian Partnership for Social Justice (VPSJ) is that expenditure on food tends to be one of the least important considerations when households are dealing with competing demands on an inadequate income. - See more at: http://www.safefood.eu/Publications/Research-reports/The-cost-of-a-healthy-food-basket.aspx#sthash.RiBpj5no.dpuf A Minimum Essential Standard of Living (MESL) is derived from a negotiated consensus on what people believe is a minimum standard. It is a standard of living that meets an individual’s or a household’s physical, psychological and social needs. This is calculated by identifying the goods and services required by different household types in order to meet their needs. While an MESL is based on needs, not wants, it is a standard of living below which nobody should be expected to live. This report focuses on food, one of the 16 elements of the Minimum Essential Standard of Living (MESL) data. It is based on a methodology called Consensual Budget Standards (CBS). The report is presented in the context of increasing concerns about the issue of food poverty in the Republic of Ireland (ROI) and an increase in the number of people reporting that they do not have enough money to buy food. Recent data from The Organisation for Economic Co-operation and Development (OECD) have shown that the number of people believing they cannot afford food doubled from 4.2% in 2008 to 9% in 2014. Data from Eurostat show that in 2013, food and non-alcoholic beverage prices in Ireland were 17% higher than the EU average. Moreover, research by Carney and Maitre, using data from the Survey on Income and Living Conditions (SILC), found that one in ten people are living in food poverty in Ireland. Food poverty is defined as the inability to have an adequate and nutritious diet due to issues of affordability and access to food. This has related effects on health, culture and social participation. The 2013 data from the Survey on Income and Living Conditions (SILC) show that 1.4 million people, almost 31% of the population, suffer from deprivation. This means that they are unable to afford two items from a list of 11 very basic items (of which one is not being able to eat a meal with meat, chicken, fish or a vegetarian equivalent every second day). The highest levels of deprivation are experienced by lone parents (63%), unemployed people (55%) and people not at work because of illness or disability (53%). The experience of the Vincentian Partnership for Social Justice (VPSJ) is that expenditure on food tends to be one of the least important considerations when households are dealing with competing demands on an inadequate income. - See more at: http://www.safefood.eu/Publications/Research-reports/The-cost-of-a-healthy-food-basket.aspx#sthash.RiBpj5no.dpuf
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INTRODUCTION: Increasing health care costs, limited resources and increased demand makes cost effective and cost-efficient delivery of Adolescent Idiopathic Scoliosis (AIS) management paramount. Rising implant costs in deformity correction surgery have prompted analysis of whether high implant densities are justified. The objective of this study was to analyse the costs of thoracoscopic scoliosis surgery, comparing initial learning curve costs with those of the established technique and to the costs involved in posterior instrumented fusion from the literature. METHODS: 189 consecutive cases from April 2000 to July 2011 were assessed with a minimum of 2 years follow-up. Information was gathered from a prospective database covering perioperative factors, clinical and radiological outcomes, complications and patient reported outcomes. The patients were divided into three groups to allow comparison; 1. A learning curve cohort, 2. An intermediate cohort and 3. A third cohort of patients, using our established technique. Hospital finance records and implant manufacturer figures were corrected to 2013 costs. A literature review of AIS management costs and implant density in similar curve types was performed. RESULTS: The mean pre-op Cobb angle was 53°(95%CI 0.4) and was corrected postop to mean 22.9°(CI 0.4). The overall complication rate was 20.6%, primarily in the first cohort, with a rate of 5.6% in the third cohort. The average total costs were $46,732, operating room costs of $10,301 (22.0%) and ICU costs of $4620 (9.8%). The mean number of screws placed was 7.1 (CI 0.04) with a single rod used for each case giving average implant costs of $14,004 (29.9%). Comparison of the three groups revealed higher implant costs as the technique evolved to that in use today, from $13,049 in Group 1 to $14577 in Group 3 (P<0.001). Conversely operating room costs reduced from $10,621 in Group 1 to $7573 (P<0.001) in Group 3. ICU stay was reduced from an average of 1.2 to 0 days. In-patient stay was significantly (P=0.006) lower in Groups 2 and 3 (5.4 days) than Group 1 (5.9 days) (i.e. a reduction in cost of approximately $6,140). CONCLUSIONS: The evolution of our thoracoscopic anterior scoliosis correction has resulted in an increase in the number of levels fused and reduction in complication rate. Implant costs have risen as a result, however, there has been a concurrent decrease in those costs generated by operating room use, ICU and in-patient stay with increasing experience. Literature review of equivalent curve types treated posteriorly shows similar perioperative factors but higher implant density, 69-83% compared to the 50% in this study. Thoracoscopic Scoliosis surgery presents a low density, reliable, efficient and effective option for selected curves. A cost analysis of Thoracoscopic Scoliosis Surgery using financial records and a prospectively collected database of all patients since 2000, demonstrating a clear cost advantage compared to equivalent posterior instrumentation and fusion.
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This paper develops a dynamic model for cost-effective selection of sites for restoring biodiversity when habitat quality develops over time and is uncertain. A safety-first decision criterion is used for ensuring a minimum level of habitats, and this is formulated in a chance-constrained programming framework. The theoretical results show; (i) inclusion of quality growth reduces overall cost for achieving a future biodiversity target from relatively early establishment of habitats, but (ii) consideration of uncertainty in growth increases total cost and delays establishment, and (iii) cost-effective trading of habitat requires exchange rate between sites that varies over time. An empirical application to the red listed umbrella species - white-backed woodpecker - shows that the total cost of achieving habitat targets specified in the Swedish recovery plan is doubled if the target is to be achieved with high reliability, and that equilibrating price on a habitat trading market differs considerably between different quality growth combinations. © 2013 Elsevier GmbH.