148 research outputs found

    On the Tropicalization of the Hilbert Scheme

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    In this article we study the tropicalization of the Hilbert scheme and its suitability as a parameter space for tropical varieties. We prove that the points of the tropicalization of the Hilbert scheme have a tropical variety naturally associated to them. To prove this, we find a bound on the degree of the elements of a tropical basis of an ideal in terms of its Hilbert polynomial. As corollary, we prove that the set of tropical varieties defined over an algebraically closed valued field only depends on the characteristic pair of the field and the image group of the valuation. In conclusion, we examine some simple examples that suggest that the definition of tropical variety should include more structure than what is currently considered.Comment: 19 page

    Stable determination of an inclusion by boundary measurements

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    We deal with the problem of determining an inclusion within an electrical conductor from electrical boundary measurements. Under mild a priori assumptions we establish an optimal stability estimate.Comment: 19 page

    Resurrecting Keynes to Revamp the International Monetary System

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    There is a broad consensus that the current, large U.S. current-account deficits financed with foreign capital inflows at low interest rates cannot continue forever; there is much less consensus on when the system is likely to end and how badly it will end. The paper resurrects the basic principles of the plan Keynes wrote for the Bretton Woods Conference to propose an alternative to the current international monetary system. We argue for the creation of a supranational bank money that would coexist along side national currencies and for the establishment of a new international clearing union. The new international money would be created against domestic earning assets of the Fed and the ECB. In addition to recording credit and debit entries of the supranational bank money, the new agency would determine the size of quotas, the size and time length of overdrafts, and the coordination of monetary policies. The substitution of supranational bank money for dollars would harden the external constraint of the United States and resolve the n-1 redundancy problem.Keynes Plan, external imbalances, exchange rates, international monetary system, key currency, supranational bank money

    The trade specialization of SANE: Evidence from manufacturing industries

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    This paper studies the evolution of the foreign trade specialization in manufacturing sectors of South Africa, Algeria, Nigeria and Egypt. These four countries, the so-called SANE, have recently been viewed as Africa’s best chance of producing an economic bloc whose role for Africa might be comparable to that of the BRIC economies of Brazil, Russia, India and China for the world economy. Using data on trade flows since mid-1970s, the results show that the SANE group has experienced few changes in its trade structure, which is still based on low-technology and slow-growth world demand sectors. The degree of persistence in the specialization model is higher in the case of Algeria and Nigeria, where the dependence on products based on natural resources is stronger.SANE, Trade specialization, Manufacturing, Lafay index

    The Trade Specialization of SANE:Evidence from Manufacturing Industries

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    This paper studies the evolution of the foreign trade specialization in manufacturing sectors of South Africa, Algeria, Nigeria and Egypt. These four countries, the so-called SANE, are recently viewed as Africa’s best chance of producing an economic bloc comparable to the BRIC economies of Brazil, Russia, India and China. Using data on trade flows since mid-1970s, the results show that the SANE group has experienced few changes in its trade structure, which is still based on low-technology and slow-growth world demand sectors. The degree of persistence in the specialization model is higher in the case of Algeria and Nigeria, where the dependence on products based on natural resources is stronger.SANE; Trade specialization; Manufacturing; Lafay index

    Stable determination of an inclusion in an elastic body by boundary measurements (unabridged)

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    We consider the inverse problem of identifying an unknown inclusion contained in an elastic body by the Dirichlet-to-Neumann map. The body is made by linearly elastic, homogeneous and isotropic material. The Lam\'e moduli of the inclusion are constant and different from those of the surrounding material. Under mild a-priori regularity assumptions on the unknown defect, we establish a logarithmic stability estimate. For the proof, we extend the approach used for electrical and thermal conductors in a novel way. Main tools are propagation of smallness arguments based on three-spheres inequality for solutions to the Lam\'e system and refined local approximation of the fundamental solution of the Lam\'e system in presence of an inclusion.Comment: 58 pages, 4 figures. This is the extended, and revised, version of a paper submitted for publication in abridged for

    Workers’ Effort: A Comparison Between Capitalist and Cooperative Firms

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    The purpose of this paper is to establish a comparison between capitalistic and cooperative firms by focusing on workers’ effort during productive activity in a model in which owners and/or managers suffer from information asymmetries. In our model agency relations do not mainly concern the design of incentive mechanisms but the setting of an optimal form of monitoring, centered on management control (albeit incomplete) on workers' effort during production. By using a principal-­‐agent framework, we show that in the presence of information asymmetries on the actual effort offered by each worker, the cooperative firm requires less monitoring to achieve an optimal level of worker effort. Being also owners of the firm and choosing the person responsible for management functions inside their circle, cooperative workers develop relations based on solidarity and forms of ‘peer monitoring’ which reduce monitoring costs. Consequently, the manager of the cooperative firm can devote more of his/her effort to organizational activity which increases the efficiency of the production process. Hence, in terms of working effort, governance in the cooperative firm is more efficient than in the capitalist firm. However, the opposite result is achieved when the purchasing cost of capital in the two kinds of firm is taken into consideration. Therefore, the financial constraints to the purchase of capital reduce the production efficiency of the cooperative relatively to the capitalistic firm. In addition, such constraints represent an obstacle to achieving an optimal rate of long-­‐term growth for the cooperative firm and benefiting from the related virtuous circle between increases in the level of employment and growth rate.The purpose of this paper is to establish a comparison between capitalistic and cooperative firms by focusing on workers’ effort during productive activity in a model in which owners and/or managers suffer from information asymmetries. In our model agency relations do not mainly concern the design of incentive mechanisms but the setting of an optimal form of monitoring, centered on management control (albeit incomplete) on workers' effort during production. By using a principal-­‐agent framework, we show that in the presence of information asymmetries on the actual effort offered by each worker, the cooperative firm requires less monitoring to achieve an optimal level of worker effort. Being also owners of the firm and choosing the person responsible for management functions inside their circle, cooperative workers develop relations based on solidarity and forms of ‘peer monitoring’ which reduce monitoring costs. Consequently, the manager of the cooperative firm can devote more of his/her effort to organizational activity which increases the efficiency of the production process. Hence, in terms of working effort, governance in the cooperative firm is more efficient than in the capitalist firm. However, the opposite result is achieved when the purchasing cost of capital in the two kinds of firm is taken into consideration. Therefore, the financial constraints to the purchase of capital reduce the production efficiency of the cooperative relatively to the capitalistic firm. In addition, such constraints represent an obstacle to achieving an optimal rate of long-­‐term growth for the cooperative firm and benefiting from the related virtuous circle between increases in the level of employment and growth rate.Refereed Working Papers / of international relevanc

    Essays on the Indian economy

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    Tre decenni di crescita straordinaria hanno modificato profondamente l'economia dell'India, la cui struttura centralizzata, chiusa e basata sul settore agricolo appartiene ormai al passato. Negli anni ottanta, l' India era una delle economie piÚ chiuse al mondo, ogni aspetto della produzione era controllato dal governo centrale tramite il sistema delle licenze, metà del reddito nazionale derivava dall'agricoltura e il " tasso di crescita Hindu" sembrava condannare il paese ad un persistente stato di arretratezza economica. Al contrario, l' India del 2009 è una nazione dove i servizi rappresentano piÚ di metà del Pil, è il maggior esportatore mondiale di prodotti IT e di capitale umano altamente qualificato, rappresenta uno dei principali poli di attrazione di investimenti esteri e, nonostante la crisi finanziaria mondiale, il pattern di crescita dell'economia non manifesta alcun segnale allarmante di declino. Tuttavia, nonostante i risultati di successo, l' India è tuttora la nazione che ospita la maggioranza dei poveri e piÚ di un terzo dei bambini malnutriti di tutto il mondo. Inoltre, la maggior parte della popolazione attiva è occupata in agricoltura e piÚ della metà del reddito nazionale trae origine dall' economia sommersa. Se l' India sia in grado di trasformare l'attuale pattern di crescita economica in un processo di sviluppo economico rimane dunque una questione ancora aperta. La seguente tesi racchiude quattro ricerche separate e si inserisce nel dibattito riguardante i meccanismi e le conseguenze della crescita economica dellâ India. Lo scopo è quello di analizzare e valutare i cambiamenti dell'economia indiana avvenuti negli ultimi venticinque anni sotto quattro aspetti differenti: il processo di riforme, la distribuzione del reddito, la creazione di nuovi posti di lavoro e la specializzazione commerciale. Si scopre che l'India, se confrontata ad esempio con altre economie come Cina e Russia, ha implementato una strategia di crescita specifica e contestuale alle proprie caratteristiche economico-strutturali. Tale strategia si è contraddistinta per un graduale approccio alle riforme che hanno migliorato la performance economica del paese e stimolato il rapido passaggio dall' agricoltura ai servizi. Tuttavia, la terziarizzazione dell'economia indiana è stata accompagnata dal mancato sviluppo del tessuto industriale. La debolezza del settore manifatturiero, come dimostrato dal suo scarso contributo alla formazione del Pil, sembra essere la causa dei problemi strutturali dell' economia quali il divario di reddito fra gli stati dell' Unione, la " crescita senza occupazione" e il grado di specializzazione commerciale basato sui settori meno dinamici del commercio mondiale. I principali aspetti e risultati dei singoli capitoli possono essere cosÏ riassunti: - Il Capitolo 1 studia i differenti pattern di crescita di Cina, India e Russia considerando e comparando i processi di riforma che hanno favorito e accompagnato gli alti tassi di crescita. Analizzando le trasformazioni settoriali avvenute nelle tre economie, si dimostra che le strategie di crescita presentano specifiche caratteristiche in termini di gradualismo e strumenti di politica economica utilizzati. Vengono presi in considerazione gli effetti della crescita economica sulle disparità regionali in termini di reddito, valutando se la recente crescita del reddito nazionale sia stata omogeneamente distribuita all' interno dei tre paesi. Utilizzando la T di Theil e le matrici delle probabilità di transizione, si conclude che la disparità di reddito tra gli stati indiani e tra le province cinesi è aumentata nel corso del tempo. In particolare, vi è una crescente divergenza nei redditi fra le regioni piÚ interne e prettamente agricole e quelle piÚ ricche dislocate lungo la costa. Nel caso della Russia, il divario inter-regionale viene alimentato dalla presenza degli idrocarburi nelle regioni nell' ovest della Siberia. - Nel Capitolo 2 si analizza il processo di convergenza/divergenza tra gli stati dell' India. Dopo aver esaminato le principali riforme economiche implementate durante gli ultimi tre decenni nell'Unione Indiana, si conduce uno studio econometrico sulle determinanti della crescita economica nel quadro neoclassico del modello di Solow. Uno degli aspetti principali dello studio è l' applicazione di tecniche di econometria spaziale a complemento delle tecniche neoclassiche. Si controlla per due effetti spaziali distinti, l'effetto di distanza inter-regionale e l'effetto di condivisione di un confine comune. I risultati suggeriscono che la disparità tra regioni piÚ ricche e piÚ povere è costantemente aumentata durante gli anni ottanta e novanta. PiÚ specificamente, si rileva che i vincitori sono gli stati che hanno beneficiato maggiormente delle riforme di liberalizzazione economica, grazie anche al vantaggio derivante dalla loro posizione geografica e alla presenza del settore dei servizi giÚ sviluppato. Le regioni che invece mostrano un'arretratezza economica piÚ marcata sono risultate essere quelle piÚ interne e prive dello sbocco al mare, altamente popolate, poco innovative e con la presenza predominante del settore agricolo. - Il Capitolo 3 prende in considerazione il problema della "jobless growth" (crescita senza occupazione) nel settore manifatturiero indiano. Nonostante l' incredibile performance economica degli ultimi venticinque anni, l'India è caratterizzata da u' alta divergenza fra il tasso di crescita dell'economia e il tasso di crescita dell'occupazione. L' elasticità dell' occupazione rispetto al Pil è diminuita nel tempo e la capacità dell' economia indiana di creare nuovi posti di lavoro sembra essere limitata. Come risultato, piÚ del 60 per cento dei lavoratori indiani è ancora impiegata in agricoltura, mentre il 94 per cento della forza lavoro è occupata nell'economia sommersa. Questo studio analizza il fenomeno della " jobless growth" in India utilizzando un contesto Kaldoriano in cui i legami fra agricoltura e industria entrano nella domanda di lavoro tramite la ragione di scambio fra i due settori. Inoltre, si considera il ruolo del settore informale sulla crescita dell' occupazione formale. Utilizzando dati panel sul settore manifatturiero formale dei 15 maggiori stati indiani tra il 1980 e il 2004, le stime System-GMM mostrano che gli stati con una piÚ alta domanda di prodotti industriali proveniente dall'agricoltura hanno avuto una piÚ alta crescita dell' occupazione. In aggiunta, in quegli stati in cui il peso del settore informale è cresciuto nel tempo, il problema della "jobless growth" è risultato essere maggiore. - Infine, nel Capitolo 4, si studia l' evoluzione della specializzazione commerciale nel settore manifatturiero indiano, utilizzando dati sul commercio internazionale a partire dal 1985. I settori con un piÚ basso grado di contenuto tecnologico dominano le categorie di prodotto in cui l'India è specializzata. Al contrario, nei settori ad alto contenuto tecnologico, l' India mostra un' alta dipendenza dalle importazioni. Tuttavia, l'India ha mostrato miglioramenti nel grado di specializzazione in alcuni fra i piÚ dinamici settori in termini di domanda mondiale.Three decades of extraordinary growth have drastically modified the economy of India, and its centralized, closed and agriculture-based structure definitely belongs to the past. In the early 1980s, India was one of the most closed countries in the world, every step of production was under the license system governed by the central state, half of the national income derived from agriculture and the " Hindu rate of growth" seemed to condemn the economy to a persisting level of backwardness. By contrast, India in 2009 is a country where more than half of GDP comes from service activities, it is the world major exporter of IT products and highly-skilled human capital, it represents one of the most attractive destinations for global companiesâ investments and, despite the global financial crisis, the pace of growth of the economy does not display any alarming signal of decline. Nevertheless, despite these successful results, India is the country where the majority of worldâ s poor lives, accounting for more than one third of the worldwide malnourished children. Moreover, the largest part of Indian working population finds employment in rural areas and more than half of the national income comes from unregistered activities. The question about whether India will be able to transform its economic growth pattern into an economic development process is therefore still open. This thesis consists of four separate essays and is a contribution to the debate concerning the mechanisms and the consequences of the Indian growth experience. It investigates and evaluates the changing Indian economy in the last two and a half decades under four main aspects: the process of reforms, the distribution of income, the creation of new jobs and the specialization of trade. It is found that India implemented a context-specific growth strategy, especially if compared to other economies like China or Russia. This strategy was characterised by a gradual approach to economic and policy reforms that enhanced the performance of the country and stimulated the rapid shift from agriculture to services. However, the tertiarization of India occurred at the expenses of the process of industrialization. The weakness of the manufacturing sector, as shown by its limited contribution to GDP formation, appears to explain a number of structural problems of the economy. In fact, it is associated with a widening of the income gap between landlocked and coastal states of the Union; it is responsible for the jobless growth dilemma; and it constrains the degree of Indian trade specialization to the less dynamic sectors of world trade. The contents and the main findings of each chapter can be summarized as follows: - Chapter 1 studies the different patterns of growth of China, India and Russia by exploring and comparing the processes of reforms that have generated and accompanied their high and sustained rates of growth. Focusing on the sector transformations involved into the three economies, I show that the growth strategies implemented present specific characteristics in terms of gradualism and policy choices. I explore the effects of economic growth on regional income disparities and the extent to which the recent increase in prosperity has been homogeneously distributed within each of the three giants. The analysis makes use of Theil' s T statistics and transition probability matrices to reveal that income disparities within the Indian states and Chinese provinces have increased. In particular, landlocked and rural areas are in general still far from reducing the income gap from coastal and richest regions. In the case of Russia, the great divide is fuelled by the presence of hydrocarbons resources, which tend to be concentrated in West Siberia. - Chapter 2 investigates the process of convergence/divergence across Indian states. After surveying the main economic reforms implemented during the last decades in the Indian Union, I conduct an econometric study of the determinants of economic growth in the neoclassical frame of the Solow model. One of the main novel aspects of the convergence analysis is the attention paid to the spatial pattern of growth across Indian states. Making use of spatial econometric tools, I control for two different kinds of spatial interaction: distance and neighbourhood. The results suggest that the gap between poor and rich states has constantly increased during the 1980s and the 1990s. Specifically, winners were those states that benefited the most from the recent process of reform and liberalization, thanks also to their geographical advantage and to the presence of a developed service sector. Losers were instead the landlocked and highly populated states with a predominant agricultural sector and a low level of innovation. - Chapter 3 investigates the jobless growth scenario affecting Indian manufacturing. Despite the incredible economic performance in the last twenty-five years, India maintains a high discrepancy between the rate of growth of the economy and the rate of growth of employment. Labour elasticity to output has decreased over time and the capability of the Indian economy to generate employment seems to be limited. As a result, more than 60% of Indian workers are still employed in agriculture and 94% of total labour force can be found in the unregistered segment of the economy. This paper analyzes the jobless growth problem in India in terms of a Kaldorian framework where the linkages between agriculture and industry enter labour demand through the changes in the terms of trade between the two sectors. Moreover, I investigate the role of the unorganized sector in influencing the growth of the registered employment. Using a dynamic panel dataset on registered manufacturing from the 15 major Indian states over the period 1980-2004, System-GMM estimates show that states with a higher growth of demand for industrial goods originating from agriculture also exhibit a higher growth of employment. In addition, in those states where the weight of the unregistered manufacturing has risen over time, the jobless growth problem has worsened. - Finally, Chapter 4 examines the pattern of international trade specialization in Indian manufacturing since the mid-1980s by using data on trade flows. Low-technology sectors still dominate the categories for which India exhibits the largest degree of trade specialization. By contrast, high-technology sectors are prevalent among the categories for which India is import-dependent. Significantly, India has experienced an improvement in the degree of specialization in some of the most dynamic sectors of world trade

    High resolution map of migrants in the EU

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    This report describes a data set generated from the harmonization and spatial processing of official census statistics collected from National Statistical Institutes in 8 EU Member States (France, Germany, Ireland, Italy, Netherlands, Portugal, Spain and UK). The dataset provides a map at high spatial resolution of the population with migrant background in these Member States. The uniqueness of the data set resides both the high level of spatial resolution (cells of 100 by 100 m) and the large geographical coverage which is including almost 45 thousand local administrative units. From this data set it is possible to calculate indicators of concentration of migrants, diversity and spatial residential segregation which can support comparative research and policies on the local aspect of the integration of migrants in the EU.JRC.E.6-Demography, Migration and Governanc
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