Aciphylla species (wild spaniard/speargrass) are an iconic component of the Australasian high country flora, but their reproductive system is enigmatic. They are insect-pollinated dioecious mast seeders (synchronous highly variable seed production), which seems maladaptive. The resource supply to pollinators is highly variable, yet dioecious plants are dependent on pollinators, and dioecious masting requires male and female plants to flower synchronously. Floral display in Aciphylla is relatively large, with tall inflorescences bearing thousands of flowers, suggesting that plants would not have the resources to produce such large stalks every year. But why do they have such huge inflorescences in the first place? I tested whether pollinator attraction is providing an economy of scale which favours intermittent production of very large inflorescences, by manipulating floral display size during a high-flowering year and measuring insect visitation rates and seed set (female reproductive success). Using space-for-time substitution and selective removal of male inflorescences, I also tested whether female seed set was affected by distance to flowering male plants (i.e. changes in local pollen availability) to see if flowering asynchrony would reduce pollination success. Bags were used to exclude pollination by insects and test for wind pollination, and hand pollination was done to test for pollen limitation. Insect surveys suggest that Aciphylla has a generalist pollination system (to avoid satiating a specialist pollinator during 'mast' years'). Male inflorescences received significantly more visits than females, and some seeds were set inside bags (although only 20-30%), suggesting wind pollination may occur at low levels. Seed set rate was higher for taller inflorescences with greater flowering length in A. aurea but tall inflorescences with excess flowers led to a decrease in seed set rates in A. scott-thomsonii. Hand pollination significantly increased seed set rates although these effects were not as large as expected (e.g. 10% increases from natural to hand-pollinated inflorescences were typical). There was no evidence for resource limitation in any species. Female plants in dense flowering populations had higher seed set rates, and individual floral display size in females was particularly important when females were 'isolated' from males. Insect visitation rates were generally higher on inflorescences with a larger floral display, suggesting that display size is important for pollinator attraction. Overall, these results suggest that the pollinator-attraction benefits of such a large floral display (at both the plant and population level) are possibly providing an economy of scale, although the relative effects are small.

Submitted by ANTONIO FRANCISCO DE LIMA NETO (antoniolimaneto@terra.com.br) on 2017-02-08T19:13:17Z No. of bitstreams: 1 DISSERTAÇÃO.pdf: 1830177 bytes, checksum: 4c734ffcfbcedb51122db2df7d287909 (MD5) / Approved for entry into archive by Renata de Souza Nascimento (renata.souza@fgv.br) on 2017-02-08T19:59:40Z (GMT) No. of bitstreams: 1 DISSERTAÇÃO.pdf: 1830177 bytes, checksum: 4c734ffcfbcedb51122db2df7d287909 (MD5) / Made available in DSpace on 2017-02-10T11:59:55Z (GMT). No. of bitstreams: 1 DISSERTAÇÃO.pdf: 1830177 bytes, checksum: 4c734ffcfbcedb51122db2df7d287909 (MD5) Previous issue date: 2017-01-31 / This work aims to analyze economies of scale in the Brazilian Financial System after the introduction of Plano Real (2001 – 2009), which led to a significant expansion of local bank portfolio. To do so, this paper compares results obtained from a minimum cost function, with Transcendental Logarithmic (TRANSLOG) specification, and administrators’ preferred cost function, which maximizes management utility, derived with the aid of Almost Ideal Demand System (AIDS). The results show economies of scale for the chosen set of Financial Conglomerates when the AIDS technique is applied in contrast to the diseconomies of scale evidenced with the aid of TRANSLOG technique. The results come in line with the findings of international research, pointing out the benefits of application of the AIDS technique in the field of banking efficiency, given the multiplicity of objectives bank administrators must currently pursue. / O presente trabalho tem por objetivo analisar economias de escala no Sistema Financeiro Brasileiro (SFN) no período 2001 a 2009 (pós implementação do Plano Real), quando ocorreu significativa expansão do portfólio dos bancos brasileiros. Para tanto, vale-se de técnicas de estimação de uma função de custo mínimo, com especificação Transcendental Logarithmic (TRANSLOG), e de uma função custo preferida pela administração bancária, que maximiza sua utilidade, derivada com a técnica Almost Ideal Demand System (AIDS).Os resultados apontam economias de escala para o conjunto dos conglomerados financeiros analisados, quando se utiliza a técnica AIDS, em oposição aos resultados obtidos com a técnica TRANSLOG, que aponta retornos decrescentes de escala para os mesmos conglomerados. Os resultados confirmam achados de pesquisas internacionais, ressaltando-se os potenciais benefícios da aplicação da técnica AIDS no campo de eficiência bancária, dada a multiplicidade de objetivos que a administração bancária tem que perseguir nos dias atuais.

Este trabalho procurou analisar o sistema produtivo da atividade leiteira em Minas Gerais, identificando a capacidade dos produtores em permanecer no negócio, a longo prazo, através da estimação da função custo translogarítmica. O estudo demonstrou que os produtores analisados ainda praticam altos custos por unidade produzida, sugerindo baixa eficiência dos estabelecimentos e falhas na administração do empreendimento. Os resultados econométricos revelam a possibilidade de ganhos de escala, no que se refere à alocação e melhor aproveitamento dos recursos, ou seja, as propriedades apresentam economias de escala. No entanto, retornos crescentes de escala não são compatíveis com a existência de mercados competitivos, sinalizando que os produtores enfrentam restrições geradas pelas imperfeições de mercado. O conhecimento dessas imperfeições é essencial à formulação de políticas econômicas e de organizações privadas que visem ao desenvolvimento econômico deste mercado, que atualmente é o sexto maior do mundo. Além disso, os resultados das elasticidades mostram que o produtor é mais sensível às variações de preços na mão-de-obra do que às variações nos demais fatores, reduzindo em maior proporção o uso do trabalho na produção, à medida que seu preço aumenta. Isto evidencia a principal característica regional da produção leiteira no país, que é o uso intensivo do fator trabalho. Também foi identificado que o os medicamentos, alimentos e energia, denominados no estudo de fator dispêndio, são os mais difíceis é o mais difícil de serem substituídos na produção, devido às particularidades no uso dos componentes deste insumo. Por fim, os valores positivos encontrados para as elasticidades parciais de substituição de Allen confirmam a substitutibilidade entre os fatores. / This study analyzes the production system of dairy farming in Minas Gerais, identifying the ability of producers to stay in business in the long run, by estimating the translog cost function. The study showed that the producers still have high costs per unit, suggesting low efficiency of facilities and mismanagement of the enterprise. The econometric results show the existence of economies of scale in relation to allocation and better utilization of resources. However, increasing returns to scale are not compatible with the existence of competitive markets, indicating that producers face constraints generated by market imperfections. Knowledge of these shortcomings is essential to the formulation of economic policies and private organizations that address the economic development of this market, which is currently the sixth largest in the world. In addition, the results show that elasticities of the producer is more sensitive to price changes in labor than to changes in other factors, reducing the use of a higher proportion of labor in production, as its price increases. This highlights the main feature of the regional dairy production in the country, which is the intensive use of labor. The study has also identified that the use of selected inputs, such as medication, food and energy, identified in the study as expense factor, are the most difficult to replace due to peculiarities in the use of components of this material. Finally, the positive values founds for the partial Allen elasticities of substitution confirm the substitutability between factors.

In a widely acclaimed contribution to Management International Review, Hennart (2007) challenged one of the mainstream theories of International Business, the S-curve relationship between multinationality and performance, by arguing that there is no positive impact on performance aside from the scale enhancing effect resulting from increasing multinationality. We examine his arguments by analyzing 3876 firms from Canada, Germany, Japan, the UK and the US over the period from 2002 to 2016. We find that the empirical evidence for a direct positive impact of multinationality on performance is not convincing. However, increasing multinationality leads to a significantly higher firm performance via the economies of scalechannel. Multinationality seems to be more important as a means to increase scale for firms from small home markets compared to firms from large domestic markets. Intangible assets appear to amplify the impact of scale on performance much more than the impact of multinationality on performance. In the end, it’s size that matters.

A fim de atender uma demanda interna e externa crescente, a produção de frangos de corte, de excepcional desempenho no agronegócio brasileiro, tem se expandido, nos últimos anos, para outros estados do país além dos tradicionais produtores. Particularmente nos estados da região Centro-Oeste, importantes projetos avícolas foram implantados, incorporando-se novos produtores ao sistema. Observa-se que, alguns destes avicultores da nova fronteira possuem áreas de terra maiores e produzem em maior escala que os produtores da região tradicional. Justifica-se, assim, a investigação empírica para determinar o tamanho ótimo da atividade de produção de frangos de corte, a fim de inferir sobre a existência ou não de economias de escala no setor. Adicionalmente, procura-se avaliar a possibilidade dos pequenos produtores avícolas das regiões tradicionais serem afetados, diante da concorrência com a produção em grande escala do Centro-Oeste brasileiro. Neste sentido, o objetivo central do presente trabalho é o de estimar uma função de custo transcendental logarítmica (translog) para a atividade de produção de frangos de corte, por conseguinte, verificar a existência de economias de escala no setor. O referencial teórico do estudo é o da teoria microeconômica dos custos de produção e dualidade. Os dados utilizados para a análise são de corte transversal, obtidos a partir de pesquisa de campo, realizada de setembro a dezembro de 2002, em uma amostra de 229 (duzentos e vinte e nove) granjas produtoras de frango de corte dos principais estados produtores do País. O trabalho inclui, também, a caracterização sócio-econômica dos produtores de frango pesquisados. Conclui-se que a amostra representa bem as realidades regionais, com o predomínio de produtores com pequenas propriedades e menor capacidade produtiva no Sul do País e Minas Gerais e produtores com propriedades maiores e níveis de produção mais elevados nos estados do Centro-Oeste brasileiro. As estimativas de economias de escala obtidas para o modelo de custos translog apontam uma escala ótima de produção de aproximadamente 110 mil Kg de frango vivo, que poderia ser obtida em propriedades com 3.500m2 de aviário, aproximadamente. Os resultados sugerem a comprovação da hipótese que as economias de escala estejam determinando uma nova configuração para o setor de produção de frangos de corte no Brasil. Porém, o tamanho ótimo da exploração, obtido no trabalho empírico, é menor que o sugerido por algumas empresas de abate do setor. Estas propriedades, com produções superiores, estariam operando com deseconomias, o que poderia ocasionar uma certa pressão dos produtores por uma melhor remuneração da atividade por parte da agroindústria parceira. Além do mais, a própria estrutura da produção em parceira, implantada nos novos projetos do Centro-Oeste brasileiro, composta por um pequeno número de grandes produtores, expõe a agroindústria e fortalece os produtores quanto a negociações de preços. As evidências sugerem, também, a comprovação da hipótese de que algumas características da pequena produção podem minimizar a importância destas economias e, muito provavelmente, são determinantes para a manutenção da produção em pequena escala nas regiões produtoras tradicionais. / Pushed by a growing demand, the Brazilian broiler production sector, which faced an outstanding development in recent years, spread to other states in the country. Important new projects were set up, particularly in the Center-West region, incorporating new producers to the system. The recognition that many of these new producers have larger operations than those of the traditional areas motivated this study, which seeks to determine the optimal scale of operation in the activity. The extent to which this will affect the small production in the more traditional areas will also be examined. The main objective of this paper is to estimate a translog cost function for the broiler production activity in Brazil, to infer about the existence of scale economies in the sector. The theoretical approach relies on the microeconomic theory of production costs and duality. We use cross-section data obtained through a field research undertake during the period of September to December 2002, in a sample of 229 broiler-producing units in the main producer states in Brazil. The paper also addresses a socio-economic characterization of the surveyed units. The sample reflects regional detail of production structure, with smaller producers concentrated in Southern Brazil and Minas Gerais state, while larger producers concentrate in the Center-West region. The economies of scale estimates point to an optimal scale of production around 110 thousand kilos of broiler hens that could be produced in a plant with approximately 3,500 m2. The results point to the hypothesis that the presence of scale economies could be determining a new production structure for the sector in Brazil. The optimal size found, however, is smaller than what has been suggested by some processing industries. Some properties, then, would be operating with diseconomies, beyond the optimal scale of production, what could cause pressures for rising prices. Moreover, the structure of production in partnership proposed by the processing industry in the Center-West region, comprised by a smaller number of larger scale producers give the latter greater price bargaining power. And, finally, the evidence found also suggests that some aspects of the small production system work to reduce the importance of these scale economies, and are determinant to keep the small-scale operations in the traditional regions.

A fim de atender uma demanda interna e externa crescente, a produção de frangos de corte, de excepcional desempenho no agronegócio brasileiro, tem se expandido, nos últimos anos, para outros estados do país além dos tradicionais produtores. Particularmente nos estados da região Centro-Oeste, importantes projetos avícolas foram implantados, incorporando-se novos produtores ao sistema. Observa-se que, alguns destes avicultores da nova fronteira possuem áreas de terra maiores e produzem em maior escala que os produtores da região tradicional. Justifica-se, assim, a investigação empírica para determinar o tamanho ótimo da atividade de produção de frangos de corte, a fim de inferir sobre a existência ou não de economias de escala no setor. Adicionalmente, procura-se avaliar a possibilidade dos pequenos produtores avícolas das regiões tradicionais serem afetados, diante da concorrência com a produção em grande escala do Centro-Oeste brasileiro. Neste sentido, o objetivo central do presente trabalho é o de estimar uma função de custo transcendental logarítmica (translog) para a atividade de produção de frangos de corte, por conseguinte, verificar a existência de economias de escala no setor. O referencial teórico do estudo é o da teoria microeconômica dos custos de produção e dualidade. Os dados utilizados para a análise são de corte transversal, obtidos a partir de pesquisa de campo, realizada de setembro a dezembro de 2002, em uma amostra de 229 (duzentos e vinte e nove) granjas produtoras de frango de corte dos principais estados produtores do País. O trabalho inclui, também, a caracterização sócio-econômica dos produtores de frango pesquisados. Conclui-se que a amostra representa bem as realidades regionais, com o predomínio de produtores com pequenas propriedades e menor capacidade produtiva no Sul do País e Minas Gerais e produtores com propriedades maiores e níveis de produção mais elevados nos estados do Centro-Oeste brasileiro. As estimativas de economias de escala obtidas para o modelo de custos translog apontam uma escala ótima de produção de aproximadamente 110 mil Kg de frango vivo, que poderia ser obtida em propriedades com 3.500m2 de aviário, aproximadamente. Os resultados sugerem a comprovação da hipótese que as economias de escala estejam determinando uma nova configuração para o setor de produção de frangos de corte no Brasil. Porém, o tamanho ótimo da exploração, obtido no trabalho empírico, é menor que o sugerido por algumas empresas de abate do setor. Estas propriedades, com produções superiores, estariam operando com deseconomias, o que poderia ocasionar uma certa pressão dos produtores por uma melhor remuneração da atividade por parte da agroindústria parceira. Além do mais, a própria estrutura da produção em parceira, implantada nos novos projetos do Centro-Oeste brasileiro, composta por um pequeno número de grandes produtores, expõe a agroindústria e fortalece os produtores quanto a negociações de preços. As evidências sugerem, também, a comprovação da hipótese de que algumas características da pequena produção podem minimizar a importância destas economias e, muito provavelmente, são determinantes para a manutenção da produção em pequena escala nas regiões produtoras tradicionais. / Pushed by a growing demand, the Brazilian broiler production sector, which faced an outstanding development in recent years, spread to other states in the country. Important new projects were set up, particularly in the Center-West region, incorporating new producers to the system. The recognition that many of these new producers have larger operations than those of the traditional areas motivated this study, which seeks to determine the optimal scale of operation in the activity. The extent to which this will affect the small production in the more traditional areas will also be examined. The main objective of this paper is to estimate a translog cost function for the broiler production activity in Brazil, to infer about the existence of scale economies in the sector. The theoretical approach relies on the microeconomic theory of production costs and duality. We use cross-section data obtained through a field research undertake during the period of September to December 2002, in a sample of 229 broiler-producing units in the main producer states in Brazil. The paper also addresses a socio-economic characterization of the surveyed units. The sample reflects regional detail of production structure, with smaller producers concentrated in Southern Brazil and Minas Gerais state, while larger producers concentrate in the Center-West region. The economies of scale estimates point to an optimal scale of production around 110 thousand kilos of broiler hens that could be produced in a plant with approximately 3,500 m2. The results point to the hypothesis that the presence of scale economies could be determining a new production structure for the sector in Brazil. The optimal size found, however, is smaller than what has been suggested by some processing industries. Some properties, then, would be operating with diseconomies, beyond the optimal scale of production, what could cause pressures for rising prices. Moreover, the structure of production in partnership proposed by the processing industry in the Center-West region, comprised by a smaller number of larger scale producers give the latter greater price bargaining power. And, finally, the evidence found also suggests that some aspects of the small production system work to reduce the importance of these scale economies, and are determinant to keep the small-scale operations in the traditional regions.

本文將設定一 Translog 多產品成本函數模型，以估計台灣旅行業之規模 經濟 (Economies of Scale) 及多樣化經濟 (Economies of Scope)程度 。在 Translog 多產品成本函數模型中，係以廠商所經營之四項業務，包 括來華觀光、出國旅遊、國民旅遊及代辦業務等，當作四種不同的產品， 而要素投入則為勞動與資本租賃。實證結果顯示，台灣旅行業普遍存在規 模經濟的現象。此結果可能導致：第一，所謂``靠行''的形成；第二，規 模較小的廠商可能根據本身的競爭優勢與經營特色而採取市場區隔化策略 ，以服務某特定之顧客群；第三，現有旅行業廠商之間的合併，或是來自 產業外的廠商藉購併進入旅行業市場，以從事多角化經營。另外，就產品 生產效率而言，我們以多樣化經濟存在與否認為，來華觀光與出國觀光之 間、來華觀光與國民旅遊之間，以及出國觀光與國民旅遊之間，因其業務 關聯性不大，而無法發揮資源共用共享的效果，因此不適合聯合生產。而 出國觀光與代辦業務之間，因業務關聯性大，因此若能聯合生產，則必然 能夠產生綜效。至於來華觀光與代辦業務之間，以及國民旅遊與代辦業務 之間，雖無明顯之證據顯示其具有聯合生產之優勢，但若存在閒置產能， 或是因某種業務之專業性不高，致使人力資源之轉換成本不大時，亦不排 除聯合生產之可能。

There is an urgent need for wastewater treatment plants (WWTPs) to adapt to a rise in water and energy demands, prolonged periods of drought, climate variability, and resource scarcity. As population increases, minimizing the carbon and energy footprints of wastewater treatment, while properly managing nutrients is crucial to improving the sustainability WWTPs. Integrated resource recovery can mitigate the environmental impact of wastewater treatment systems; however, the mitigation potential depends on various factors such as treatment technology, resource recovery strategy, and system size. Amidst these challenges, this research seeks to investigate the environmental sustainability of wastewater treatment plants (WWTPs) integrating resource recovery (e.g., water reuse, energy recovery and nutrient recycling) in different contexts (developing versus developed world) and at different scales (household, community, and city). The over-arching hypothesis guiding this research is that: Context and scale impact the environmental sustainability of WWTPs integrated with resource recovery. Three major research tasks were designed to contribute to a greater understanding of the environmental sustainability of resource recovery integrated with wastewater treatment systems. They include a framework development task (Chapter 2), scale assessment task (Chapter 3), and context assessment task (Chapter 4). The framework development task includes a critical review of literature and models used to design a framework to assess the environmental sustainability of wastewater treatment and integrated resource recovery strategies. Most studies used life cycle assessment (LCA) to assess these systems. LCA is a quantitative tool, which estimates the environmental impact of a system over its lifetime. Based on this review, a comprehensive system boundary was selected to assess the life cycle impacts of collection, treatment, and distribution over the construction and operation and maintenance life stages. Additionally, resource recovery offsets associated with water reuse, energy recovery, and nutrient recycling are considered. The framework’s life cycle inventory includes material production and delivery, equipment operation, energy production, sludge disposal, direct greenhouse gas (GHG) emissions, and nutrients discharged to the environment. Process-based LCA is used to evaluate major environmental impact categories, including global impacts (e.g., carbon footprint, embodied energy) and local impacts (e.g., eutrophication potential). This is followed by an interpretation of results using sensitivity or uncertainty analysis. The scale assessment task investigates how scale impacts the environmental sustainability of three wastewater treatment systems integrated with resource recovery in a U.S. context. Household, community, and city scale systems using mechanized technologies applicable to a developed world setting were investigated. The household system was found to have the highest environmental impacts due high electricity usage for treatment and distribution, methane emissions from the septic tank, and high nutrient discharges. Consequently, the life cycle impacts of passive nutrient reduction systems with low energy usage at the household level merit further investigation. The community scale system highlights trade-offs between global impacts (e.g., embodied energy and carbon footprint) and local impacts (e.g., eutrophication potential) where low nutrient pollution can be achieved at the cost of a high embodied energy and carbon footprint. The city scale system had the lowest global impacts due to economies of scale and the benefits of integrating all three forms of resource recovery: Energy recovery, water reuse, and nutrient recycling. Integrating these three strategies at the city scale led to a 49% energy offset, which mitigates the carbon footprint associated with water reuse. The context assessment task investigates how context impacts the environmental sustainability of selected community scale systems in both Bolivia and the United States. In this task, rural developing world and urban developed world wastewater management solutions with resource recovery strategies are compared. Less mechanized treatment technologies used in rural Bolivia were found to have a lower carbon footprint and embodied energy than highly mechanized technologies used in urban United States. However, the U.S. community system had a lower eutrophication potential than the Bolivia systems, highlighting trade-offs between global and local impacts. Furthermore, collection and direct methane emissions had more important energy and carbon implications in Bolivia, whereas treatment electricity was dominant for the U.S. community system. Water reuse offsets of embodied energy and carbon footprint were higher for the U.S community system, because high quality potable water is replaced instead of river water. In contrast, water reuse offsets of eutrophication potential were high for the Bolivia systems, highlighting the importance of matching treatment level to end-use application. One of the Bolivia systems benefits from the integration of water, energy, and nutrient recovery leading to beneficial offsets of both global and local impacts. This research can potentially lead to transformative thinking on the appropriate scale of WWTPs with integrated resource recovery, while highlighting that context lead to changes in the dominant contributors to environmental impact, appropriate technologies, and mitigation strategies.

Moll (1991) has criticised the proposal that demand restructuring should act as the impetus for economic growth in a post-apartheid South Africa on the grounds of, a lack of empirical support. The demand restructuring thesis is premised on two empirically testable assertions: firstly that realisable economies of scale are greater in labour-intensive wage goods sectors than in luxury goods and secondly that in manufacturing as a whole labour can easily substitute for capital. While a number of studies employing either the Cobb-Douglas (Cobb & Douglas, 1948) or Constant Elasticity of Substitution (CES) ( Arrow, Chenery, Minhas & Solow, 1961) functions have attempted to quantify these features of technology, their conclusions are potentially invalid. Both functions impose the maintained hypotheses of homotheticity, homogeneity and seperability a priori. As primary hypothesis tests regarding the magnitude of parameters depend on the validity of both the hypothesis being tested and the underlying maintained hypotheses, the plausibility of maintained hypotheses is an important consideration when choosing a functional form for econometric analysis. Homotheticity and homogeneity constrain the theoretical determinants of economies of scale and seperability. The theoretical determinants of substitution thus limit the contexts in which functions which embody these hypotheses are likely to be appropriate. The mathematical concept of duality has permitted the development of flexible, general functions, such as the Transcendental Logarithmic Cost Function (Christensen, Jorgensen and Lau, 1971, 1973), which rather than imposing, permits the testing of the most commonly imposed maintained hypotheses. By applying this function to three sub-sectors of South African manufacturing both the validity of the commonly imposed maintained hypotheses and the empirical premises of the demand restructuring position are assessed in this dissertation. This application indicates that not only are the hypotheses of homotheticity, homogeneity and seperability invalid but that the inappropriate imposition of homotheticity, homogeneity and seperability invalid but that the inappropriate imposition of homotheticity biases estimates of scale downwards. Evidence also emerges to challenge Moll's (1991) assertions regarding the empirical validity of demand restructuring. / Thesis (M.Com.)-University of Natal, Durban, 1995.

Le vieillissement démographique en France constitue un sujet de préoccupation majeure et fait l'objet de plusieurs recherches du point de vue économique. La plupart des études mettent en évidence les effets négatifs du vieillissement sur l'économie française notamment sur les comptes de la protection sociale et le marché du travail. Récemment une nouvelle littérature relative au vieillissement émerge. Celle-ci cherche à savoir et à montrer en quoi le vieillissement peut être une opportunité pour l'économie. Cette thèse s'inscrit dans cette littérature. Elle cherche à répondre à la question suivante : Est-ce que le vieillissement peut être une opportunité pour l'économie française ? Pour répondre à cette question, la thèse explore les pistes de l'épargne et de la consommation en insistant sur la partie de la consommation. La thèse est articulée en cinq chapitres. Le chapitre 1 décrit les causes du vieillissement démographique en France et dresse un état des lieux des études qui portent sur l'effet de ce phénomène sur l'économie française. Le chapitre 2 analyse l'évolution du revenu, du niveau de consommation et du taux d'épargne au cours du cycle de vie et selon les générations afin d'appréhender l'évolution la consommation et du taux d'épargne agrégés dans une société vieillissante et avec le renouvellement des générations. Ces résultats permettent également de comparer le niveau de vie des classes d'âge et des différentes générations. Le chapitre 3 se focalise sur l'évolution de la structure de consommation selon l'âge, les générations et suite à une modification du revenu du ménage. Le chapitre 4 part du constat de la modification de la structure de consommation au cours du temps, la différence de la structure de consommation entre les ménages d'âge actif et les seniors pour estimer les échelles d'équivalence de 1979 à 2010, des seniors et des ménages d'âge actif. Ces échelles permettent de comparer le niveau de vie des seniors et des ménages d'âge actif en tenant compte des économies d'échelles réalisées au sein des différents ménages. Enfin le chapitre 5 utilise un modèle d'équilibre général pour quantifier l'effet du vieillissement sur la structure de consommation, productive et de l'emploi. / The ageing population in France is a subject of major concern and has been the subject of several studies from the economical perspectives. Most of studies highlight the negative effects of aging on the French economy, particularly on social protection accounts, the labor market. Recently a new literature on ageing emerges. It seeks to know and show how ageing can be an opportunity for the economy. This thesis is part of this literature. It seeks to answer the following question: Is Ageing can be an opportunity for the French economy? To answer to this question, the thesis explores the tracks of savings and consumption insisting on the consumption. The thesis is organized in five chapters. Chapter 1 describes the causes of ageing in France and provides an overview of studies covers the effect of this phenomenon on the French economy. Chapter 2 analyzes the evolution of income, consumption levels, and savings rates over the life cycle and according to the generations, to understand the evolution of aggregate consumption and aggregate savings rate in a society that's facing ageing and the renewal generations. These results also allow us to compare standards of living of age groups and different generations. Chapter 3 focuses on the evolution of consumption structure by age, generations. It provides also information about evolution of consumption structure when the household income changes. Chapter 4 began from the observation of the change in structure consumption over time, the difference in consumption structure between working-age households and seniors to estimate equivalence scales from 1979 to 2010, seniors and working-age households. These scales are used to compare the standards of living of seniors and working-age households, taking into account economies of scale achieved within different households. Finally Chapter 5 uses a general equilibrium model to quantify the effect of aging on the structure of consumption, productive and employment.