1,685 research outputs found

    Can the distributional impacts of macroeconomic shocks be predicted? A comparison of the performance of macro-micro models with historical data for Brazil

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    What was the impact of Brazil's 1998-99 currency crisis-which resulted in a change of exchange rate regime and a large real devaluation-on the occupational structure of the labor force and the distribution of incomes? Would it have been possible to predict such effects ahead of the crisis? The authors present an integrated macro-micro model of the Brazilian economy in 1998. The model consists of an applied general equilibrium macroeconometric component, connected through a set of linkage aggregate variables to a microeconomic model of household incomes. The authors use this framework to predict the employment and distributional consequences of the 1999 Brazilian currency crisis, based on 1998 household survey data. They then test the predictive performance of the model by comparing its simulated results with the actual household survey data observed in 1999. In addition to the fully integrated macro-micro model, the authors also test the performances of the microeconometric model on its own, and of a"representative household groups"approach. They find that the integrated macro-micro econometric model, while still inaccurate on many dimensions, can actually predict the broad pattern of the incidence of changes in household incomes across the distribution reasonably well, and much better than the alternative approaches. The authors conclude that further experimentation with these tools might be of considerable potential usefulness to policymakers.Labor Policies,Payment Systems&Infrastructure,Economic Theory&Research,Banks&Banking Reform,Environmental Economics&Policies,Economic Theory&Research,Environmental Economics&Policies,Macroeconomic Management,Inequality,Economic Stabilization

    Online Construction of Wavelet Trees

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    The wavelet tree (WT) is a flexible and efficient data structure for representing character strings in succinct space, while allowing for fast generalised rank, select and access operations. As such, they play an important role in modern text indexing methods. However, despite their popularity, not many algorithms have been published concerning their construction. In particular, while the WT is capable of representing a sequence of length n over an alphabet of size m in nlg m+o(nlg m) bits, much more space is typically used for its construction. Here we propose an O(nlg m)-time online method for the construction of the WT, requiring no prior knowledge about the input alphabet. The proposed algorithm is conceptually simpler than other state-of-the-art methods, while having comparable time performance and being more space-efficient in practice, since it performs just one pass over the input text and uses little extra space other than for the structure itself, as shown both theoretically and empirically

    Seasonal Patterns of Herbage Accumulation Dynamics in Marandu Palisadegrass Subjected to Intensities of Continuous Stocking Management

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    It is relatively well reported in the literature that pastures can have similar forage net accumulation when managed with contrasting structures. However, we hypothesized that the patterns of forage accumulation dynamics of pastures managed at different canopy heights is dependent on environmental conditions. The experimental treatments were four canopy heights (10, 20, 30, and 40 cm), allocated to experimental units according to a randomized complete block design with four replicates and evaluated throughout four contrasting environmental seasons (Summer, Autumn, Winter-Early Spring, and Late Spring). Under favourable growing conditions greater forage accumulation was observed in pastures maintained taller; on the contrary, under more stressful conditions, net forage accumulation rate reduced as canopy height increased. Such patterns of responses were related to compensations between tiller population density and tissue flows during summer and late spring and the reduced capacity of taller canopies to compensate lower population with greater growth rates during autumn and winter-early spring. Pastures subjected to intensities of continuous stocking management change their patterns of forage growth as they transitioned from favourable to more abiotic stressful conditions suggesting that warm-season perennial grasses demand seasonal adjustments in grazing heights in order to maximize herbage production

    Environmental Risk Assessment Based on High-Resolution Spatial Maps of Potentially Toxic Elements Sampled on Stream Sediments of Santiago, Cape Verde

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    Geochemical mapping is the base knowledge to identify the regions of the planet with critical contents of potentially toxic elements from either natural or anthropogenic sources. Sediments, soils and waters are the vehicles which link the inorganic environment to life through the supply of essential macro and micro nutrients. The chemical composition of surface geological materials may cause metabolic changes which may favor the occurrence of endemic diseases in humans. In order to better understand the relationships between environmental geochemistry and public health, we present environmental risk maps of some harmful elements (As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, V, and Zn) in the stream sediments of Santiago, Cape Verde, identifying the potentially harmful areas in this island. The Estimated Background Values (EBV) of Cd, Co, Cr, Ni and V were found to be above the Canadian guidelines for any type of use of stream sediments and also above the target values of the Dutch and United States guidelines. The Probably Effect Concentrations (PEC), above which harmful effects are likely in sediment dwelling organisms, were found for Cr and Ni. Some associations between the geological formations of the island and the composition of stream sediments were identified and confirmed by descriptive statistics and by Principal Component Analysis (PCA). The EBV spatial distribution of the metals and the results of PCA allowed us to establish relationships between the EBV maps and the geological formations. The first two PCA modes indicate that heavy metals in Santiago stream sediments are mainly originated from weathering of underlying bedrocks. The first metal association (Co, V, Cr, and Mn; first PCA mode) consists of elements enriched in basic rocks and compatible elements. The second association of variables (Zn and Cd as opposed to Ni; second PCA mode) appears to be strongly controlled by the composition of alkaline volcanic rocks and pyroclastic rocks. So, the second PCA mode is also considered as a natural lithogenic mode. The third association (Cu and Pb; third PCA mode) consists of elements of anthropogenic origin

    Hemispheric asymmetry in the sunspot cycle as a nonextensive phenomenon

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    The appearance of dark sunspots over the solar photosphere is not considered to be symmetric between the northern and southern hemispheres. Among the different conclusions obtained by several authors, we can point out that the North-South asymmetry is a real and systematic phenomenon and is not due to random variability. In the present work, we selected the sunspot area data of a sample of 13 solar cycles divided by hemisphere extracted from the Marshall Space Flight Centre (MSFC) database to investigate the behavior of probability distributions using an out-of-equilibrium statistical model a.k.a non-extensive statistical mechanics. Based on this statistical framework, we obtained that the non-extensive entropic parameter qq has a semi-sinusoidal variation with a period of \sim22 year (Hale cycle). Among the most important results, we can highlight that the asymmetry index q(A)q(A) revealed the dominance of the northern hemisphere against the southern one. Thus, we concluded that the parameter q(A)q(A) can be considered an effective measure for diagnosing long-term variations of the solar dynamo. Finally, our study opens a new approach to investigating solar variability from the nonextensive perspective.Comment: 17 pages, 2 tables and 5 figures. Submitted to Solar Physic

    Strategies for the management of the marine shoreline in the orla araranguá project (Santa Catarina, Brazil)

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    The Orla Project is a tool of the Brazilian Coastal Management resultant of joint action between the Environment Ministry and the Planning Ministry. This project articulates the three spheres of the government (federal, state, and municipal) and society. Its actions seek the management of the coastal spaces, approaching the environmental and heritage politics. The construction of a Plan for the Integrated Management of the Coastline occurs through workshops with the development of methodologies of diagnosis construction, classification and formulation of scenarios. The classification of the coastline integrates the strategic planning, which will subsidize the decision making process to reach the desired scenarios. Araranguá municipality started its workshops in October 2014, with lectures and discussions between technicians from the federal and state governments, and coordination by the municipal government. During the project period, a field day and more than 40 workshops were developed, which had the participation of the community and public managers. As a result of the workshops, the coastline was sectored by its landscape, typology (exposed, semi-exposed, and sheltered), and levels of occupation in five sectors (S1 to S5). The project identified 40 problems in the area, some recurrent in all sectors and a few specific of some places. In order to solve these problems, 80 actions and measures with different priorities were defined. From the workshops of the Orla Project, it was possible to identify the need to create rules for the use of Araranguá coastline, thus enabling its conservation and helping its sustainable development

    Desfolhamento artificial durante a formação do botão floral do girassol

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    In order to quantify reductions in leaf area which can be tolerated by sunflower plants (Helianthus annuus L.), an experiment was carried out at the Estação Experimental Agronômica of Universidade Federal do Rio Grande do Sul, in Guaíba, RS, Brazil, during the 1982/83 growing season. Plants were defoliated in two dates during the budding stage: when inflorescence head was visible, but tightly surrounded by young leaves, and when inflorescence began to open, with ray florets visible. In each of those dates eight defoliation levels were applied: removal of the leaves of the upper, medium and lower thirds of plant, individually; combination of these levels two by two; removal of all leaves, and an undefoliated check. There were no signiticant differences between defoliation dates for grain yield, grain weight, grain number in heads and head diameter. However, plant height, dry weight of stem plus head, and leaf area index varied with defoliation dates. Ali defoliation levels decreased grain yield in relation to check, with reductions varying from 16 to 100%, except for treatments where leaves were removed from the lower third of the plant and from the medium third. The levels of leaf removal affected statistically all characteristics evaluated.Com o objetivo de quantificar reduções da área foliar que as plantas de girassol (Helianthus annuus L.) podem tolerar, foi desenvolvido um trabalho na Estação Experimental Agronômica da UFRS, em Guaíba, RS, em 1982/83.  As plantas foram desfolhadas em duas épocas durante o estádio de formação do botão floral, quando a inflorescência era visível, porém firmemente circundada por folhas jovens, e quando estavam começando a abrir as flores radiais. Em cada época, foram aplicados oito níveis de desfolhamento: remoção das folhas do terço superior, médio e inferior, individualmente; combinações dos terços, dois a dois; remoção de todas as folhas, e testemunha sem remoção de folhas. Não se observaram diferenças significativas entre épocas de desfolhamento para rendimento, peso de grãos, número de grãos por capítulo e diâmetro de capítulo. Entretanto, a estatura de plantas, peso seco de caule + capítulo e IAF mantido na planta variaram com a época de desfolhamento. Todos os níveis de desfolhamento reduziram o rendimento de grãos em relação à testemunha, com decréscimos variando de 16 a 100%, exceto os tratamentos com remoção das folhas do terço inferior e remoção das folhas do terço médio. Os níveis de remoção de folhas afetaram estatisticamente todas as características avaliadas
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