Дисертації з теми "Economic modelling"
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1
Clements, Michael P. "Cointegration and dynamic econometric modelling." Thesis, University of Oxford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334980.
2
Biekpe, Nicholas Budeo. "Modelling currency volatility and returns." Thesis, Queen's University Belfast, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.264084.
3
Oliinyk, V. "Modelling of ecology-economic systems." Thesis, Видавництво СумДУ, 2009. http://essuir.sumdu.edu.ua/handle/123456789/8234.
4
Fatouros, Dimitrios Michael. "Mathematical modelling for international tax planning." Thesis, Imperial College London, 1998. http://hdl.handle.net/10044/1/7954.
5
Clyde, W. C. "A study of exchange rate modelling." Thesis, University of Edinburgh, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372198.
6
Ferrante, Francesco. "Technical change and environmental policy modelling." Thesis, University of York, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283539.
7
Lundbergh, Stefan. "Modelling economic high-frequency time series." Doctoral thesis, Handelshögskolan i Stockholm, Ekonomisk Statistik (ES), 1999. http://urn.kb.se/resolve?urn=urn:nbn:se:hhs:diva-637.
8
Dorsey, Ronald. "Economic and statistical modelling in cricket." Thesis, University of Salford, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492410.
Анотація:
Professional cricket is a sport rich in readily available data and provides fertile ground for the analysis of a wide range of economic issues. Despite this, until recent years there has been a relatively sparse amount of academic research into the economics of cricket compared to other sporting activities. This thesis considers four issues relevant to English professional cricket: player movement and exit behaviour; the impact of toss and weather on championship outcomes; the effect of central contracts on county productivity; relative age effects in professional cricket.
9
Makriyannis, Elpida. "Intelligent systems for modelling economic policies." Thesis, University College London (University of London), 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.407455.
10
Metris, Aline. "Technical and economic modelling of biofilters." Thesis, Teesside University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.686444.
11
Ponti, Giovanni Benedetto. "Continuous-time selection dynamics and their applications in economic modelling." Thesis, University College London (University of London), 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.264190.
12
Cook, Stephen. "Essays on macroeconometric modelling with reference to consumer's expenditure." Thesis, University of Oxford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361958.
13
Foster, Timothy. "Hydro-economic modelling of groundwater-fed irrigation." Thesis, Imperial College London, 2015. http://hdl.handle.net/10044/1/42248.
Анотація:
Expansion of groundwater-fed irrigation has enhanced agricultural productivity, while simultaneously causing large reductions in groundwater storage. Hydro-economic modelling provides a valuable tool for evaluating trade-offs between agriculture and aquifer sustainability. However, a central argument in this thesis is that the reliability of integrated analysis of groundwater systems may be affected by the failure to consider adequately the variables influencing field-level irrigation decisions and the dynamic aquifer responses to those choices. This thesis addresses this limitation of existing research through three main contributions to the literature. In Chapter 2, a new model of farmers' individual field-level groundwater-fed irrigation decision making is developed. Innovations include the explicit consideration of the role of soil moisture in intraseasonal irrigation scheduling, and evaluation of the impacts of weather variability and well yield on crop production. Application to a case study in the High Plains region of the United States demonstrates that low well yields limit significantly irrigated area and demand for groundwater. Furthermore, it is shown that this important behavioural response can not be captured by existing models that do not consider instantaneous supply constraints imposed by well yield. In Chapter 3, a combination of empirical analysis of observation data, and numerical simulations using the model developed in Chapter 2, are conducted to generate insights about the feedbacks between groundwater and agriculture. Reductions in well yield are shown to have large negative impacts on the productivity of irrigation whereas, contrary to previous assumptions, the response of irrigation behaviour to increased groundwater pumping lifts is found to be minimal. Importantly, this result highlights the need for integrated models to consider a broader range of factors influencing the sustainability of agricultural groundwater use. In Chapter 4, a novel hydro-economic modelling framework is presented that integrates the model of farmers' individual irrigation decision making with a distributed multi-scale groundwater flow model. The model extends the scope of existing research by using pump head-capacity curves to quantify the effect of changing aquifer storage on well yields. Advantages of the modelling framework for policy analysis in coupled agricultural groundwater systems are demonstrated. Specifically, it is shown that the long-term sustainability of irrigated agriculture is influenced by intraseasonal and interannual changes in well yield that depend on famers' pump choice and expectations about future dynamic aquifer responses. Moreover, the model demonstrates that managing the rate of well yield decline may have positive long-term impacts on both agricultural production and farmer welfare that have not been recognised in previous research.
14
Newman, Russell. "Modelling economic bubbles : is Web 2.0 next." Thesis, University of Southampton, 2015. https://eprints.soton.ac.uk/381237/.
Анотація:
The Web 2.0 phenomenon has produced a number of technology companies that in various rounds of venture capital funding, have attracted very indicative valuations. Following these rising valuations, Investment Banks took an interest in the sector. However, while the companies concerned seem stable as private entities, their novel approach to business makes their financial characteristics difficult to predict. Parallels are drawn between the 2001 dot-com bubble and the current Web 2.0 sector. This thesis highlights a dependency between modern highlights a dependency between modern web companies, and the established technology sector. It aims to identify the extent to which the contemporary technology sector (encompassing Web 2.0) has exhibited characteristics similar to those of the dot-com bubble. to that end, this thesis identifies characteristics of modern and historic bubbles, and uses them to formulate a hypothetical set of indicators, in the form of a conceptual model. To determine whether these indicators exist in real data, a novel, repeatable statistical test is developed. It first identifies statistical heuristics representative of bubble circumstances, and then compares other periods to them. Thus, given sufficient data, any period may be tested. Periods are analysed prior, during and after the dot-com bubble. During the dot-com bubble, consistently strong venture capital activity is observed, and linked to the growth in people using the internet. This is indicative of the poor decision-making by investors, documented at the time. In recent periods, patterns in venture capital investment describe an industry that is much more cautious that before, reducing the probability of the formation of a similar bubble. Looking at the past, this thesis observes investor activity that 'caused' the dot-com bubble as early as 1995-96, which raises questions about when the bubble started, and the lead-times on market collapses.
15
Vera-Toscano, Esperanza. "Modelling the labour market behaviour of women in rural canada." Thesis, University of Aberdeen, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302482.
Анотація:
This thesis develops and applies the neo-classical approach to labour supply to analyse differences between rural and urban women's labour market behaviour. Thus, one of the questions addressed is - what are the socio-economic factors affecting the labour supply of women in rural areas, and, thus do they differ between rural and urban female workers? Further beyond the general issue as to whether rural labour markets are functioning in the same way as their urban counterparts, the study also considers whether the labour market outcomes of women in poor households differ from the rest of the rural female workforce and/or their urban counterparts. First, an in-depth exploration of rural women is presented, focusing on the major barriers faced by women when entering rural labour market. Further explanations are also provided on the additional limitations among the rural poor workforce. Second, background information of employment in rural areas of Canada and, more specifically, aggregate evidence of particular differences in labour market behaviour are presented. Thus, we will have both theoretical and empirical work motivations for modelling rural-urban differences. Finally, through the use of the Survey of Labour and Income Dynamics individuals' and other socio-economic factors such as individual and household characteristics, job attitudes and place of residence are controlled for in order to model, at a micro/individual level, the labour market behaviour of women both in rural and urban areas. In particular, emphasis is placed on labour market participation, wages and hours of work supplied. Given the lack of previous economic studies in this field, this thesis represents a reasonable first step to the economic analysis of the impact of various socio-economic factors on any rural-urban differences.
16
Ray, S. K. "Modelling the world jute economy : A study in market imperfections." Thesis, University of Cambridge, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372903.
17
TROMBETTA, FEDERICO. "MODELLING THE EFFECTS OF ECONOMIC CRISIS ON THE TYPE OF GOVERNMENT." Doctoral thesis, Università Cattolica del Sacro Cuore, 2015. http://hdl.handle.net/10280/6224.
Анотація:
Questa tesi contribuisce alla letteratura di economia politica attraverso l’analisi degli effetti di una crisi economica sulla tipologia di governo. In particolare, ci si concentra su due tipologie di governo che possono essere viste come anomalie empiricamente correlate a fenomeni di crisi economica e finanziaria: il populismo e la tecnocrazia.
Dopo una rassegna critica della letteratura esistente, si sviluppano due distinti modelli di teoria dei giochi. Il primo analizza il populismo nel contesto di una relazione principale-agente tra l’elettore e il politico. Concentrandosi su come la probabilità che si affermi un governo populista è influenzata dai parametri che catturano la situazione economica del Paese, si dimostra che, in un contesto di crisi economica, è più probabile che il governo attui provvedimenti populisti.
Il secondo modello spiega la comparsa di un governo tecnocratico (e in parte anche la sua stabilità) in un sistema politico in cui gli agenti principali sono due partiti e, in alcuni casi, un gruppo di tecnocrati. Qui si prova che il governo tecnocratico ha più probabilità di emergere in un contesto di crisi economica, quando il parlamento è equamente diviso e quando la distanza ideologica tra i due partiti è sufficientemente grande.This thesis contributes to the literature on theoretical political economy analyzing the effects of economic crisis on the types of government. In particular, we focus on two types of government that can be seen as anomalies empirically related with the emergence of financial and economic crisis: populism and technocracy. After a critical survey of the existing literature on those topics, we develop two different game-theoretical models. The first one studies populism in the context of a standard political-agency relationship between a voter and a politician. We see how the likelihood of the emergence of a populist government is affected by parameters representing the economic conditions of a country, and we find that, in a context of economic crisis, the government is more likely to make populist decisions. The second model explains the emergence of a technocratic government (and captures some issues related to its stability) in a post-election partisan politics setting where the main players are two parties and possibly a group of technocrats. We prove that the technocratic government is more likely to emerge in a context of economic crisis, when the parliament is evenly split and the ideological distance between the two parties is big enough.
18
Solgård, Stian Bu. "Modelling, simulation and control of macro economic systems." Thesis, Norwegian University of Science and Technology, Department of Engineering Cybernetics, 2009. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9023.
Анотація:
Today's Basel-type banking system is compared with a 100% reserve banking system. Furthermore, negative interest rate on deposits is introduced for these two systems thus two new models are introduced. Eventually all four models are compared with each other in terms of debt crisis mechanisms and if they are prone to enter a liquidity trap. The comparing is done for debt to GDP ratio around a certain ratio of 60% thought to give neutral confidence, thus the effect from confidence dynamics can be excluded for these simulations.
19
Villegas, Ramirez Andres. "Mortality : modelling, socio-economic differences and basis risk." Thesis, City University London, 2015. http://openaccess.city.ac.uk/13574/.
Анотація:
During the last two centuries the developed world experienced a persistent increase in life expectancy. Although past trends suggests that life expectancy will continue to increase, there is considerable uncertainty surrounding the future evolution of mortality. In addition, past mortality improvements have not been shared equally across the population, resulting in a widening of socio-economic inequalities in mortality. The uncertainty and socio-economic variability of life expectancy pose a challenge for the design of pension systems and the management of longevity risk in pension funds and annuity portfolios. This thesis is devoted to the investigation of the trends and financial implications of socio-economic differences in mortality. It comprises three parts. The first part introduces new modelling techniques for the quantification of socio-economic mortality differentials in aggregate and cause-specific mortality, which are applied in the study of the relationship between mortality and deprivation in the English population. The second part evaluates the suitability of several multipopulation stochastic mortality models for assessing basis risk in longevity hedges and provides guidelines on how to use these models in practical situations. Finally, the third part introduces new modelling tools which aim to permit a more effective and widespread use of stochastic mortality models.
20
Pink, Joshua. "Pharmacologically-based mechanistic modelling in health economic evaluation." Thesis, Bangor University, 2012. https://research.bangor.ac.uk/portal/en/theses/pharmacologicallybased-mechanistic-modelling-in-health-economic-evaluation(3fb34521-4fab-4a4c-bf7f-f6fd41772f26).html.
Анотація:
This thesis concerns the linking together of the currently distinct teclmiques of pharmacokinetic-pharmacodynamic and health economic modelling. These have limitations, with economic models being empirical and thus hard to extrapolate outside the evidence base where they are constructed, and challenging to implement early in the drug development process. Pharmacokinetic-pharmacodynamic models, by contrast, are mechanistic but produce a limited range of outputs, not generating all the values useful to infonn decision making. Pharmacokinetic-pharmacodynamic-pharmacoeconomic models, by linking these approaches, have the potential to overcome these limitations. The feasibility, validity and applicability of such an approach are assessed through two case studies. The first contains both retrospective and prospective simulations ofrituximab for the treatment of follicular lymphoma. Retrospective analyses allow simulated results to be compared with trial-based data, and show an acceptable degree of concordance between the two methods. The prospective simulation of a trial currently recruiting will enable comparisons with the results of the trial, when these become available. The second and larger case study uses anticoagulation and stroke prophylaxis for patients with atrial fibrillation as an example. The end result is a full, prospective simulation of genotype dosed warfarin compared with both standard clinical dosing and a number of newly available oral anticoagulants. To make such an analysis possible, necessary prerequisite work was undertaken with the construction of a discrete event simulation to extrapolate both trial and simulation results to a lifetime horizon and an indirect comparison of all available treatments, to ensure all possible alternatives are considered in the analysis.
21
Baldwin, Elizabeth. "Modelling preferences in economics." Thesis, University of Oxford, 2014. https://ora.ox.ac.uk/objects/uuid:8abebfd3-58df-4223-83b8-ce2f43b5dc90.
Анотація:
This thesis considers the economics of preferences in two different contexts. First it examines damages from climate change. I argue that our ignorance of the welfare implications of higher levels of warming, as well as scientific uncertainty in precisely what might trigger these scenarios, imply that our tastes and beliefs are incomplete (in the sense of Galaabaatar and Karni, 2013). That is, there are many 'plausible' ways to evaluate a given scenario. In Chapter 1, then, I develop this theory, and use it to formally separate climate impacts into three sorts: those understood well, those understood badly, and those representing the worst possible scenario. I provide a generalisation of the 'dismal theorem' of Weitzman (2009a), and address the question of policy choice: prices versus quantities (cf. Weitzman, 1974). Chapter 2 is an example of the analysis propounded in Chapter 1. I explore the sensitivity of the social cost of carbon to assumed damages from 4C warming, to the assumed extent of CO2 emissions, and to the modelling of the climate and carbon cycles. The analysis shows that differing prior assumptions can alter our evaluation of policy by orders of magnitude. The second part of this thesis regards preferences for indivisible goods. In Chapter 3, which is joint work with Paul Klemperer, I introduce to this field the 'tropical hypersurface', being those prices at which an agent's demand changes. Simple geometric features of this set tell us the precise trade-offs that interest the agent. Thus we develop a new taxonomy of valuations, `demand types'; familiar notions such as substitutes and complements are examples. Finally, we provide a necessary and sufficient condition on these `demand types' for existence of competitive equilibrium, which implies several existing results, as well as new and quite different examples.
22
Psaradakis, Zacharias. "Econometric modelling in systems of cointegrated variables : applications to the Greek economy." Thesis, University of Southampton, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315507.
23
Puthenkalam, John Joseph. "Modelling a new economic growth thought for developing economies with particular reference to economies in transition." Thesis, University of Glasgow, 1996. http://theses.gla.ac.uk/2034/.
24
Delfino, Doriana. "Economic-epidemiological analysis of tuberculosis : modelling the demographic-epidemiological implications of economic growth and public health investment." Thesis, University of York, 2001. http://etheses.whiterose.ac.uk/10936/.
25
Allen, Christopher Bellett. "Supply-side economics : structural econometric modelling of producer pricing and factor demand decisions." Thesis, London Business School (University of London), 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339000.
26
Brenton, P. A. "An application of consumer demand theory to the modelling of bilateral trade flows." Thesis, University of East Anglia, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376078.
27
Safarzynska, Karolina, Roy Brouwer, and Marjan Hofkes. "Evolutionary modelling of the macro-economic impacts of catastrophic flood events." Elsevier, 2013. http://dx.doi.org/10.1016/j.ecolecon.2013.01.016.
Анотація:
This paper examines the possible contribution of evolutionary economics to macro-economic modelling of flood impacts to provide guidance for future economic risk modelling. Most macro-economic models start from a neoclassical economic perspective and focus on equilibrium outcomes, either in a static or dynamic way, and describe economic processes at a high level of aggregation. As a consequence, they typically fail to account for the complexity of social interactions and other behavioural responses of consumers and producers to disasters, which may affect the macroeconomic impacts of floods. Employing evolutionary principles and methods, such as agent-based modelling, may help to address some of the shortcomings of current macro-economic models. We explore and discuss the implications of applying consumer and producer heterogeneity, bounded rationality, network effects, social and technological learning, co-evolution and adaptive policy-making concepts into existing economic frameworks for the assessment of macro-economic impacts of floods. (authors' abstract)
28
Galbraith, J. W. "Modelling the formation of expectations." Thesis, University of Oxford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381848.
29
Kenc, Turalay. "Dynamic general equilibrium tax modelling : a study of the UK in the 1980's." Thesis, University of York, 1992. http://etheses.whiterose.ac.uk/9807/.
30
Giorgioni, Gianluigi. "Essays on a monetary union : the case of the CFA Franc zone." Thesis, Liverpool John Moores University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.299056.
31
Milne, Catherine E. "The economic modelling of sheep ectoparasite control in Scotland." Thesis, University of Aberdeen, 2004. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=128366.
Анотація:
In this study, data collected in a survey of Scottish sheep farmers was used to corroborate and augment secondary data available in the literature on sheep ectoparasites and their control in 1999/2000. The data was used to design and construct a decision tree model, which was used to determine probability weighted profit-maximising control strategies for six flock types/size groups that were representative of Scottish sheep farms. Organophosphate (OP) based dips, applied in both the autumn and spring/summer, were found to be the profit-maximising control strategy for five flock types/size groups. The exception was for small (100-ewe) lowground flocks, where two applications of cypermethrin in pour-on formulation maximised the avoidable disease losses. Each of these strategies can give rise to animal welfare, human health and /or environmental externalities. OP dips can damage human health and the environment but minimise animal welfare losses, and cypermethrin pour-on, while non-damaging to human health and the environment, can result in some avoidable welfare losses, as ectoparasite control is less effective than for OP dips. Using multi-criteria analysis (MCA), the economics of sheep ectoparasite control from a social standpoint has also been examined. Some profit-maximising control strategies do not necessary maximise social benefits. A conflict can arise between the farmer and society. The minimum cost that society would need to be willing to accept in order to finance possible incentives for sheep farmers to switch from the profit-maximising control strategy to strategies that provide different bundles of social benefits is estimated.
32
Carrasco, Torrecilla Luis Roman. "Modelling for pest risk analysis : spread and economic impacts." Thesis, Imperial College London, 2009. http://hdl.handle.net/10044/1/4702.
Анотація:
The introduction of invasive pests beyond their natural range is one of the main causes of the loss of biodiversity and leads to severe costs. Bioeconomic models that integrate biological invasion spread theory, economic impacts and invasion management would be of great help to increase the transparency of pest risk analysis (PRA) and provide for more effective and efficient management of invasive pests. In this thesis, bioeconomic models of management of invasive pests are developed. The models are applied to three cases of study. The main case looks at the invasion in Europe by the western corn rootworm (WCR), Diabrotica virgifera ssp. virgifera LeConte (Coleoptera: Chrysomelidae). A range of quantitative modelling approaches was employed: (i) dispersal kernels fitted to mark-release-recapture experimental data; (ii) optimal control models combined with info-gap theory; (iii) spatially explicit stochastic simulation models; and (iv) agent-based models. As a result of the application of the models new insights on the management of invasive pests and the links between spread and economic impacts were gained: (i) current official management measures to eradicate WCR were found to be ineffective; (ii) eradication and containment programmes that are economically optimal under no uncertainty were found out to be also the most robustly immune policy to unacceptable outcomes under severe uncertainty; (iii) PRA focusing on single invasive pests might lead to management alternatives that dot not correspond to the optimal economic allocation if the rest of the invasive pests sharing the same management budget are considered; (iv) the control of satellite colonies of an invasion occurring by stratified dispersal is ineffective when a strong propagule pressure is generated from the main body of the invasion and this effect is increased by the presence of human-assisted long-distance dispersal; and (v) agent-based models were shown to be an adequate tool to integrate biological invasion spread models with economic analysis models.
33
Ludwig, Alexander. "The Macroeconomics of Demographic Change - Essays on Economic Modelling." [S.l. : s.n.], 2005. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB11947808.
34
Olner, Dan. "An agent-based modelling approach to spatial economic theory." Thesis, University of Leeds, 2014. http://etheses.whiterose.ac.uk/6525/.
Анотація:
This thesis presents an agent-based modelling framework, leading to a ‘transmission belt’ model connecting supply and demand in a spatial setting, as a step towards understanding the “complex, integrated, tightly-coupled global fabric of exchange” (Korowicz 2010 p.2) that makes up the modern spatial economy. Informed by a careful unpacking of economic modelling ideas, the ‘transmission belt’ model succeeds in producing a stable equilibrium of consumption and production across space. The motivation for creating the model framework is as follows. While some argue ‘it is better to assume that moving goods is essentially costless’ (Glaeser and Kohlhase 2004) because space costs are so low, others point out that a future of ‘oil depletion’ (Sorrell et al. 2009) and high carbon prices due to climate change mean that the implications of future cost changes are not well understood. The thesis examines the most prominent economic approach to space costs, geographical economics (GE), which finds ways to avoid key modelling problems imposed by space but has a tight ‘mathematical straightjacket’(Martin 1999) of assumptions. This thesis keeps to simple utility functions for describing actors’ preferences, but uses an agent-based modelling approach to break out of these assumptions. While spatial agent models have dealt with a huge range of actor-environment interactions, very few examine traditional spatial economic problems. As a consequence, simple but powerful spatial economic ideas have been neglected. Much can be learned from issues that faced economists throughout the twentieth century. By closely examining these ideas, the thesis asks: what obstacles have stopped agent-based modelling from tackling the ‘big questions’ of spatial economics? The answers suggested are: a lack of research directly tackling the space of ‘dependencies’ in agent model development and a broader sense that it has broken all ties with history and can learn nothing from past modelling efforts.
35
Mashamhanda, Tendai. "Modelling the causality between FDI and Zimbabwe’s economic growth." Thesis, Rhodes University, 2017. http://hdl.handle.net/10962/50260.
Анотація:
The study investigates the causal nexus between economic growth and FDI in Zimbabwe for the period spanning 1976 to 2011. The bounds testing approach to cointegration and Granger causality methodology was applied and results suggest a bi-directional causal relationship between FDI and economic growth in the long run. However, the causal effect from economic growth to FDI was weak. Domestic investment, human capital and trade openness were also found to be crucial determinants of economic growth in Zimbabwe. Implementing policies that promote inflow of FDI into Zimbabwe are recommended.
36
Omran, Mohammed Fawzy. "Modelling the probability distribution of the time series stock price changes in the U.K. market." Thesis, University of Strathclyde, 1997. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21370.
Анотація:
The thesis considers different aspects of the probability distribution of the time series of stock price changes in the UK market. It places particular emphasis on the character of the volatility of the series. Chapter 2 documents some preliminary findings about changes in the FT-ALL share price index. These findings are: (1) its distribution has fat tails; (2) the BDS test rejects the hypothesis of identically, and independently distributed price changes; (3) the BDS test applied to the GARCH(l, 1) residuals, adjusted according to de Lima (1995b), indicates that Autoregressive Conditional Heteroscedasticity explains most of the nonlinearity in the FT-ALL price changes. The hypothesis of constant variance is rejected for the FT-ALL series using the Loretan and Phillips test, reported in chapter 3. An intervention model along the lines of Box and Tiao (1975) is used to model possible shifts in the variance of the FT-ALL price changes during the 1973 oil crisis and the 1987 market crash. The model allows for slow decay in the shocks effects and a different level of volatility after both crises. The results suggest that the reaction of the UK market to both crises differs only with regard to the slow decay of the shocks. The null hypothesis of constant variance is "accepted" for the residuals from the intervention model. This "acceptance" is due to the filtering of the effects of the 1973 and 1987 crisis from the FT-ALL series. The hypothesis that GARCH volatility persistence becomes insignificant when the volume of trade is included is examined in chapter 4. In a test covering the price behaviour of 57 UK companies over the period from 4/1/1988 to 28/2/1994, it is found that although the parameter estimates of the GARCH model becomes insignificant when volume is used in the conditional variance of price changes, the autocorrelations of the squared residuals still exhibit a highly significant GARCH pattern. It is argued that the GARCH-volume model of Lamoureux and Lastrapes (1990b) suffers from a multicollinearity problem, apart from the possible simultaneity bias which could lead to an inconsistent estimate of the parameter for volume. It is found that unexpected volume reduces volatility persistence. This reduction can be attributed to the strong association in the timing of innovational outliers in the price changes and unexpected volume found in the study. The results are consistent with the market depth hypothesis of Bessembinder and Seguin (1993). The GARCH model with the conditional normal, Student's t and generalized error distributions is estimated for the UK FT-ALL price changes in chapter 5. The model also considers seasonal and leverage effects. The time period for the study is chosen so as to avoid including the 1987 crash. The results suggest:( 1) volatility persistence is low after the 1987 crash; (2) the ARMA and ARCH effects, along with the seasonal effects of Monday and holidays, explain a significant part of the departure from normality; (3) there is a need for leptokurtic distribution such as the Student's t; and (4) there is no evidence for a leverage effect in the FT-ALL series. That is, positive and negative surprises tend to affect volatility in the same way.
37
Boehler, Christian Ernst Heinrich. "Mind the gap! : geographic transferability of economic evaluation in health." Thesis, Brunel University, 2013. http://bura.brunel.ac.uk/handle/2438/7170.
Анотація:
Background: Transferring cost-effectiveness information between geographic domains offers the potential for more efficient use of analytical resources. However, it is difficult for decision-makers to know when they can rely on costeffectiveness evidence produced for another context. Objectives: This thesis explores the transferability of economic evaluation results produced for one geographic area to another location of interest, and develops an approach to identify factors to predict when this is appropriate. Methods: Multilevel statistical models were developed for the integration of published international costeffectiveness data to assess the impact of contextual effects on country-level; whilst controlling for baseline characteristics within, and across, a set of economic evaluation studies. Explanatory variables were derived from a list of factors suggested in the literature as possible constraints on the transferability of costeffectiveness evidence. The approach was illustrated using published estimates of the cost-effectiveness of statins for the primary and secondary prevention of cardiovascular disease from 67 studies and related to 23 geographic domains, together with covariates on data, study and country-level. Results: The proportion of variation at the country-level observed depends on the appropriate multilevel model structure and never exceeds 15% for incremental effects and 21% for incremental cost. Key sources of variability are patient and disease characteristics, intervention cost and a number of methodological characteristics defined on the data-level. There were fewer significant covariates on the study and country-levels. Conclusions: Analysis suggests that variability in cost-effectiveness data is primarily due to differences between studies, not countries. Further, comparing different models suggests that data from multinational studies severely underestimates country-level variability. Additional research is needed to test the robustness of these conclusions on other sets of cost-effectiveness data, to further explore the appropriate set of covariates, and to foster the development of multilevel statistical modelling for economic evaluation data in health.
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Melville, Guy T. "Hydrodynamic and economic modelling of tidal current energy conversion systems." Thesis, Robert Gordon University, 2008. http://hdl.handle.net/10059/695.
Анотація:
This thesis examines the contribution of computational modelling to the development of the tidal current energy industry, against the background of increasing commercial, government, academic and public interest. It does this through the practical application of a number of computational techniques in the areas of: 1. Tidal current analysis and prediction 2. Hydrodynamic flow modelling 3. Tidal resource analysis 4. Optimised economic modelling Appropriate survey set-up is essential in gathering data. Given this, processing the data using velocity profiles; statistical techniques; and harmonic analysis can produce valuable data for site development, device design and grid management. This work developed the application of a directional and time-dependent power coefficient and demonstrates its importance in resource evaluation from tidal flow data. It further concludes that hydrodynamic flow modelling of sites prior to development is important in determining suitable sites, given the scarcity of tidal information in the areas suitable for tidal developments. The same scarcity of data, in terms of boundary conditions, interior validation points and depth does limit the accuracy of such models. The work demonstrates that using differing resource analyses can obtain dramatically different results; and develops a correlation relating energy extraction to developed energy extraction using a one dimensional channel model. In doing so it concludes that energy resource estimates may be reduced from contemporary estimates. Overall, computational modelling of tidal current energy conversion systems can have a significant contribution to their design and site development. The most significant capital costs arise from installation, decommissioning and the turbine itself, however significant reduction in the cost of energy production can result from correct placement, array size and component selection This work contributes to knowledge in a number of areas, namely: 1. It is the first published work on survey data analysis prior to deployment of a large-scale prototype tidal current energy conversion system; 2. At the time that the work was carried out, it was the first published work considering the use of the least-squared harmonic method for prediction of energy output from a tidal current energy device; 3. It is the first work to propose a directional power coefficient in the process of resource analysis for a tidal current energy conversion system; 4. The work on economic modelling was the first to produce an optimised economic model for tidal current energy conversion systems (TCECS); 5. It is the first work to use an optimised economic model for TCECSs to demonstrate the effect of device placement on the cost of energy produced; 6. It is the first work to use an optimised economic model for TCECSs to demonstrate that the cost of energy for TCECSs is minimised by maximising the rated power, given no topographical impedence; 7. It proposes a method to determine the energy resource available including energy extraction.
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Eyre, Robert W. "Complex statistical modelling of socio-economic variables in public health." Thesis, University of Warwick, 2018. http://wrap.warwick.ac.uk/106563/.
Анотація:
The statistical inference of socio-economic variables in public health is key to the design of interventions to address the many health inequalities that exist across the world. However, such inferences are achieved commonly using a small standardised library of statistical methods. Meanwhile other fields such as computer science and systems biology have seen the development of many new methods allowing for more varied and useful analyses. Here we present analyses in three important contextual areas of socio-economic variables in public health, bringing in modern and sophisticated methods in order to develop highly useful and flexible results and further expand the library of statistical methods in public health. In the first, we further develop and apply a non-linear temporal model to analyse the spread of health aspects such as mood and weight over US adolescent friendship networks by a process known as social contagion. The use of this model improves our ability to more realistically reflect patterns we expect to see result in the data from contagion. This was achieved using analysis of the Add Health dataset. In the second, we use the flexibility and complex features of Gaussian processes to analyse two different aspects of pregnancy in rural South Africa using the Agincourt HDSS dataset. First, the modelling of fertility-patterns over combinations of variables where some have established models and others do not, allowing us to incorporate such variables into our model without risking the enforcement of unjustified assumptions. Second, analysing social contagion of pregnancy risk behaviour where no social network data exists, demonstrating how the use of sophisticated methods can enable us to attempt complicated research questions. Finally, in the third we build three possible Bayesian belief network models of household food security in the Agincourt study area. The structural features of these models make them potentially highly useful causal tools that enable us to model a wide range of interventions on our system. Through these analyses we demonstrate the importance of expanding the library of statistical methods in public health to include the many modern and sophisticated methods being developed in other fields, whilst also producing findings and tools of great robustness, flexibility, and utility.
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Li, F. G. N. "Spatially explicit techno-economic optimisation modelling of UK heating futures." Thesis, University College London (University of London), 2013. http://discovery.ucl.ac.uk/1400217/.
Анотація:
This thesis describes the use of a spatially explicit model to investigate the economies of scale associated with district heating technologies and consequently, their future technical potential when compared against individual building heating. Existing energy system models used for informing UK technology policy do not employ high enough spatial resolutions to map district heating potential at the individual settlement level. At the same time, the major precedent studies on UK district heating potential have not explored future scenarios out to 2050 and have a number of relevant low-carbon heat supply technologies absent from their analyses. This has resulted in cognitive dissonance in UK energy policy whereby district heating is often simultaneously acknowledged as both highly desirable in the near term but ultimately lacking any long term future. The Settlement Energy Demand System Optimiser (SEDSO) builds on key techno-economic studies from the last decade to further investigate this policy challenge. SEDSO can be distinguished from other models used for investigating UK heat decarbonisation by employing a unique combination of extensive spatial detail, technical modelling which captures key cost-related nonlinearities, and a least-cost constrained optimisation approach to technology selection. The study yields a number of original contributions to knowledge that are relevant for policymakers. Results described in the thesis suggest that the marginal economics of UK district heating schemes are significantly improved when compared against individual heat pumps rather than gas boilers. This is relevant because under current policy direction individual heat pumps are likely to be the major counterfactual option to district heating post-2030. Results also illustrate how assumptions about technology availability can drive large shifts in optima, and that utility-scale electric heat pumps could be a key enabling technology for district heating to supply a large fraction of UK heat demand in a post-gas heating future.
41
Hedbrant, Per. "Techno-Economic Modelling of Tight Oil ProductionA Bottom-up Approach." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-320786.
Анотація:
There has been a revolution in US oil production the last decade,mainly because of production of the unconventional tight oil, and itis therefore of great interest to be able to produce reliableforecasts on future supply.The aim of this study is to develop and explore a bottom-up well-bywellmodel for tight oil production. The model is based on theinherent physics and geology of the well, together with simplemicro-economic principles. The model is made to be modular, flexibleand well grounded in practicalities. It successfully manages toreplicate historical production profile of Eagle Ford Play both withand without economic parameters. This implies the suitability of abottom-up approach for this kind of task.The model also tries to look into the future. An exploratorysimulation result suggests that a large decrease and stagnation indrilling capacity gives a convergence in oil production to aconstant level. But, the decrease in drilling capacity does notcorrespond with the decrease in oil production. Also, a low level offuture oil price could give a hyperbolic decline in production ratewhich does not seem to level off within years.
42
Dalmazzone, Silvana. "Economic activity and the resilience of ecological systems : complexity, nonlinearities and uncertainty in economic-ecological modelling." Thesis, University of York, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311013.
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Kragt, Marit Ellen. "An integrated assessment approach to linking biophysical modelling and economic valuation." Phd thesis, Canberra, ACT : The Australian National University, 2010. http://hdl.handle.net/1885/8037.
Анотація:
Changes to land use and land management in Australian catchments have led to pressures on natural resources, and concerns over water quality and ecosystem health in catchment rivers and estuaries. To increase the efficiency of natural resource management (NRM) policies that address these concerns, decision makers require information about the environmental impacts, as well as the marginal costs and benefits associated with policy decisions. Including cost-benefits estimates in NRM policy assessment provides decision makers with economic information about the trade-offs between alternative NRM actions. There are, however, few studies that have assessed the complex environmental and economic trade-offs associated with changes in catchment NRM actions in a single modelling framework. This study uses an integrated assessment (IA) approach to develop a decision support model that incorporates environmental and economic dimensions of catchment NRM, for a case-study of the George catchment in Tasmania. Various (academic and non-academic) stakeholders were consulted during the model development process, to gain an understanding of the wide variety of values that may be impacted by NRM changes. Knowledge from different sources was integrated in a single framework using Bayesian network modelling techniques. The framework incorporates three major sub-models: 1. A physically based water quality model to predict the changes in sediment and nutrient loadings in the George rivers and estuary; 2. Expert opinion and Bayesian network modelling to predict the impacts of catchment NRM changes on three ecosystem attributes: riparian vegetation, rare species and estuary seagrass area; and 3. A choice experiment (CE) survey to estimate the non-market values associated with changes in George catchment ecosystem attributes. The CE study was not only aimed at assessing catchment non-market values, but also addressed methodological challenges associated with attribute level framing and cost anchoring in CE. Rather than coupling existing information and models, synchronous data collection and model development were used to ensure tailored information exchange between the different components. The IA approach to model development highlighted several challenges in synchronizing economic and scientific research. Frequent communication was required between the stakeholders involved in the project to construct a common framework for analysis. The selection of attributes that were relevant for scientists, policy makers, and CE survey respondents was a lengthy process. Agreeing on the level of modelling detail, and predicting attribute levels based on sound scientific information, also posed considerable challenges during the model development process.
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Wheeler, Scott Barry Ross. "Mathematical foundations for the use of genetic algorithms in economic models." Title page, abstract and contents only, 2002. http://web4.library.adelaide.edu.au/theses/09PH/09phw5644.pdf.
Анотація:
"July 2002." Bibliography: leaves 119-126. !. Introduction -- 2. Preliminiaries -- 3. Genetic algorithms -- 4. Equilibria and stability in economic models -- 5. Stochastic representation of economic models -- 6. Two population models -- 7. Overview. The aim of this dissertation is to provide a mathematical foundation for the application of genetic algorithms to economic models.
45
Humala, Acuña Alberto. "Markov switching modelling of interest rate pass-through." Thesis, University of Warwick, 2005. http://wrap.warwick.ac.uk/34676/.
Анотація:
The first paper, "Interest rate pass-through and financial crises: do switching regimes matter? The case of Argentina", analyses the dynamic relationship between a money market (interbank) rate and different short-term lending rates by measuring their passthrough. Neither linear single-equation modelling nor linear multi-equation systems capture efficiently this relationship. Several financial crises alter the speed and degree of response to interbank rate shocks. Hence, a Markov switching VAR model shows the pass-through increases considerably for all market interest rates in a high-volatility scenario. The model identifies correctly the periods in which regime shifts occur, and associates them to financial crises. The second paper, "Modelling interest rate pass-through with endogenous switching regimes in Argentina", extends the scope of the Markov switching modelling by including time-varying transition probabilities. Interest rate spreads are used as leading indicators. The model allows devaluation expectations and country risks, (measured by rate spreads) to signal regime switching. Estimation results suggest that the passthrough tends to overshoot with financial instability, but to decrease if that condition is sufficiently large and long-lived. Likewise, results show a quite heterogeneous credit market, with a highly efficient transmission mechanism in the corporate segment, but considerably less in the consumer segment. The final paper, "Regime switching in interest rate pass-through and dynamic bank modelling with risks", builds a theoretical model of dynamic bank optimisation, which provides rationale to a regime-switching behaviour in the interest rate pass-through. It is shown that a regime-switching interbank rate induces a nonlinear behaviour in lending and deposit rates and (by further introducing interbank-alike regime-switching risk premiums) in the pass-through. Thus, the pass-through process is consistent with a nonlinear behaviour even if there are no asymmetric adjustment costs in the response to interbank rate shocks. An empirical application to France and Germany provide results that support these conclusions.
46
Iregui, Ana María. "Three essays on multiregional applied general equilibrium modelling." Thesis, University of Warwick, 1999. http://wrap.warwick.ac.uk/110878/.
Анотація:
In this thesis three policy issues that are of particular relevance in the economic debate are analysed using multiregional CGE models. The first of these issues is related to the welfare effects of the decentralised provision of quasi-private goods by the government. The second issue refers to the exportation of domestic taxes from developed to developing countries. And, the third issue is related to the efficiency gains from the elimination of global restrictions on international labour mobility. Two types of multiregional CGE models can be distinguished. The first type of models disaggregates the national economy into regions, whereas in the second type, regions consist of countries or groups of countries. In this thesis both types of models are used. Chapter 2 quantifies the welfare effects of decentralisation in Colombia, using a multiregional CGE model. The purpose of this chapter is to investigate to what extent will the Colombian population be better off when goods such as health and education, are delivered locally as against centrally. A provision scheme based on the median voter is considered. Neither multiregional CGE models nor schemes for public provision of quasi-private goods have been previously applied when assessing the effects of decentralisation. According to the results, the provision of health and education by regional governments improves the welfare of the Colombian population as a whole, since regional governments provide goods and services in a way that better caters to local preferences. More importantly, these welfare gains vary from 1.3% to 2.3% of GDP, a substantial magnitude especially when compared with the efficiency gains associated to the tax reforms of the early nineties. Chapter 3 investigates whether developed countries export taxes to developing countries, contributing to the deterioration of their terms of trade and welfare; that is to what extent the distribution of gains from trade is being affected not by existing tariffs in developed countries, which are already at low levels, but by their domestic taxation. An eight-region CGE model for the world economy is used. The results indicate that when factors of production are internationally immobile, developed regions do not export domestic taxes to developing regions. On the contrary, when capital is assumed to be internationally mobile developed region export capital taxes to developing regions. Regardless of the assumptions on international capital mobility, the effects of import tariffs on welfare and terms of trade are larger than those of domestic taxes. Chapter 4 computes the world-wide efficiency gains from the elimination of global restrictions on labour mobility using an eight-region CGE model. A distinctive feature of the analysis is the introduction of a segmented labour market, as two types of labour are considered: skilled and unskilled. According to the results, when labour is a homogeneous factor, the elimination of global restrictions on labour mobility generates world-wide efficiency gains that could be of considerable magnitude. When the labour market is segmented and both skilled and unskilled labour migrate, welfare gains reduce since the benefits and losses of migration are not evenly distributed within each region. When only skilled labour migrates, the world-wide efficiency gains are smaller, since this type of labour represents a small fraction of the labour force in developing regions.
47
Plourde, André. "Modelling the economic implications of offshore oil : the case of Hibernia." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25958.
Анотація:
The development and production of Canadian offshore petroleum deposits raises three key sets of issues of interest to economists. First are questions relating to the impact of royalties and taxes on producer decisions, and hence on the level and efficiency of resource taxation. Other issues concern the impacts on the overall economy during both the construction and production phases. A third set of issues relates to the distribution of powers and resource revenues between federal and provincial governments, including the links between provincial resource revenues and equalization payments.
This thesis develops a numerically tractable economic model designed to examine these issues. At the model's core is a one-to-one relationship between development plans and production profiles. This property is exploited in simulating the behaviour of a price-taking, net-present-value-maximizing producer under conditions of certainty.
The model is linked with a macroeconometric model of the Canadian economy to study the potential consequences of Hibernia, a petroleum deposit located in the Eastern Canadian offshore region. This deposit was chosen for analysis because its size, location and low costs (relative to current world oil prices) combine to raise all of the issues listed above.
In most cases studied, producer responses to government policies result in the dissipation of less than five percent of the deposit's net present value to society. Although cases are identified where these responses have more serious consequences, the resulting dissipation of potential net benefits never exceeds 15 percent. The extension of specific forms of royalty and tax relief to the producer generally reduces the distortionary effects of government policies.
The simulated exploitation of Hibernia induces small but sympathetic changes in most macroeconomic variables. The net crowding-out effects on other industries are shown to be relatively small, and to be more prevalent during the construction period.
The results suggest that the larger share of the net benefits accruing to governments flows to the provincial treasury under three of the revenue-sharing systems modelled. However, Newfoundland and Labrador would lose a substantial portion of its Hibernia revenues under all of the equalization systems modelled.Arts, Faculty of
Vancouver School of Economics
Graduate
48
Ho, Minh Trang Thi Chemical Sciences & Engineering Faculty of Engineering UNSW. "Techno-economic modelling of CO2 capture systems for Australian industrial sources." Awarded by:University of New South Wales. School of Chemical Sciences and Engineering, 2007. http://handle.unsw.edu.au/1959.4/30566.
Анотація:
Australia is recognising that carbon capture and storage (CCS) may be a feasible pathway for addressing increasing levels of CO2 emissions. This thesis presents a preliminary economic assessment and comparison of the capture costs for different Australian CO2 emission sources. The capture technologies evaluated include solvent absorption, pressure swing adsorption (PSA), gas separation membranes and low temperature separation. The capture cost estimated for hydrogen production, IGCC power plants and natural gas processing is less than A$30/tonne CO2 avoided. CO2 capture cost for iron production ranges from A$30 to A$40 per tonne CO2 avoided. Higher costs of A$40 to over A$80 per tonne CO2 avoided were estimated for flue gas streams from pulverised coal and NGCC power plants, oil refineries and cement facilities, and IDGCC synthesis gas. Based on 2004 and 2005 EU ETS carbon prices (A$30 to A$45 per tonne CO2 avoided), the cost of capture using current commercially available absorption technology may deter wide-scale implementation of CCS, in particular for combustion processes. A sensitivity analysis was undertaken to explore the opportunities for reducing costs. The high cost for capture using solvent absorption is dependent on the energy needed for solvent regeneration and the high capital costs. Cost reductions can be achieved by using new low regeneration energy solvents coupled with recycling the waste heat from the absorption process back to the steam cycle, and using low cost ???fit-for-purpose??? equipment. For membrane and PSA technologies, the capture costs are dominated by the flue gas and post-capture compressors. Operating the permeate or desorption stream under vacuum conditions provides significant cost reductions. Improvements in membrane and adsorbent characteristics such as the adsorbent loading or membrane permeability, CO2 selectivity, and lower prices for the membrane or adsorbent material provide further cost benefits. For low partial pressure CO2 streams, capture using low temperature ???anti-sublimation??? separation can be an alternative option. Low costs could be achieved by operating under low pressures and integrating with external sources of waste heat. Applying the cost reductions achievable with technology and process improvements reduces the capture and CCS costs to a level less than current carbon prices, making CCS an attractive mitigation option.
49
Santos, Carlos. "Structural breaks and outliers in economic time series : modelling and inference." Thesis, University of Oxford, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433296.
50
Magrini, Stefano. "Modelling regional economic growth : the role of human capital and innovation." Thesis, London School of Economics and Political Science (University of London), 1998. http://etheses.lse.ac.uk/868/.
Анотація:
This thesis investigates the role of human capital and innovation activity in the process of economic growth within a system of regions. It starts by reviewing existing theories of economic growth paying particular attention to the literature on “endogenous growth”, the large body of empirical literature addressing economic growth and that has investigated the “convergence issue”. A methodology based on the direct analysis of cross-sectional distributions of per capita income is then developed and applied to per capita income data for 122 European Union (EU) functionally defined regions over the period 1979-1990. The results show a clear tendency for some of the richest European regions to grow away from the others. The comparison of these results with those derived from a similar analysis for the commonly used administrative regions of the EU reveals some significant distortions imposed by adopting an administrative definition. A formal theoretical explanation of these results is then offered. In particular, it is argued that regional disparities in per capita income owe their existence to the pattern of specialisation between ‘knowledge creating’ and ‘knowledge applying’ regions. Specialisation is explained in terms of differences in the availability of useful knowledge at different locations. In the perfect foresight, stable equilibrium of the two-region model developed here, therefore, the region that specialises in innovation related activities (knowledge creating) enjoys a permanently higher level of per capita income. Moreover, it is shown that, on reasonable assumptions, a process of integration that reduces the cost of physical distance leads to faster growth in the long-run for the system as a whole, but at the expense of an increase in regional disparities. Finally, some predictions are derived and tested empirically. Using cross-sectional regressions, the fundamental determinants of the growth rate of a region are investigated. The results are supportive of the model, confirming the role played by the concentration of innovative activities and spatial spillovers of knowledge.