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Genetic analysis of average annual productivity of Nellore breeding cows (COWPROD)

ELER, J. P.; FERRAZ, J. B. S.; BALIEIRO, J. C. C.; MATTOS, E. C.
Fonte: FUNPEC-EDITORA Publicador: FUNPEC-EDITORA
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
46%
With the aim of estimating the coefficient of heritability of average annual productivity of Nellore cows (COWPROD), a data set from 24,855 animals with known pedigree was analyzed. COWPROD is defined as the amount (in kilograms) of weaned calves produced yearly by one cow during her remaining time in herd ignoring a fixed period of 365 days. COWPROD was calculated regarding three standards: a) based on the post-weaning weight from the calves ignoring any kind of adjustment (COWPROD_NAJ), b) adjusted weight for the fixed effects (COWPROD_AJFIX) and c) adjusted weight for the fixed effects and for the genetic merit of the sire (COWPROD_AJFIN). The obtained heritabilities were 0.15, 0.15 and 0.16 for COWPROD_NAJ, COWPROD_AJFIX and COWPROD_AJFIN, respectively. A complete set composed of 105,158 COWPROD records on 130,740 animals in pedigree was also analyzed for predicting the genetic merit of all animals in the data set and for the calculation of the genetic, phenotypic and residual trends. Ranking correlation was high for the adjusted and non-adjusted data, yet, for some of the animals, the difference among the genetic values was large. This would be an indication that it would be better to work always with the adjusted weaning weights. The genetic trend was positive...

Genetic associations among average annual productivity, growth traits, and stayability: A parallel between Nelore and composite beef cattle

Santana, M. L.; Eler, J. P.; Bignardi, A. B.; Ferraz, J. B S
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 2566-2574
Português
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46.08%
This study was conducted to examine the relationship among average annual productivity of the cow (PRODAM), yearling weight (YW), postweaning BW gain (PWG), scrotal circumference (SC), and stayability in the herd for at least 6 yr (STAY) of Nelore and composite beef cattle. Measurements were taken on animals born between 1980 and 2010 on 70 farms located in 7 Brazilian states. Estimates of heritability and genetic and environmental correlations were obtained by Bayesian approach with 5-trait animal models. Genetic trends were estimated by regressing means of estimated breeding values by year of birth. The heritability estimates were between 0.14 and 0.47. Estimates of genetic correlation among female traits (PRODAM and STAY) and growth traits ranged from-0.02 to 0.30. Estimates of genetic correlations ranged from 0.23 to 0.94 among growth traits indicating that selection for these traits could be successful in tropical breeding programs. Genetic correlations among all traits were favorable and simultaneous selection for growth, productivity, and stayability is therefore possible. Genetic correlation between PRODAM and STAY was 0.99 and 0.85 for Nelore and composite cattle, respectively. Therefore, PRODAM and STAY might be influenced by many of the same genes. The inclusion of PRODAM instead of STAY as a selection criterion seems to be more advantageous for tropical breeding programs because the generation interval required to obtain accurate estimates of genetic merit for PRODAM is shorter. Average annual genetic changes were greater in Nelore than in composite cattle. This was not unexpected because the breeding program of composite cattle included a large number of farms...

Estimating average annual per cent change in trend analysis

Clegg, Limin X; Hankey, Benjamin F; Tiwari, Ram; Feuer, Eric J; Edwards, Brenda K
Fonte: John Wiley & Sons, Ltd. Publicador: John Wiley & Sons, Ltd.
Tipo: Artigo de Revista Científica
Português
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46.06%
Trends in incidence or mortality rates over a specified time interval are usually described by the conventional annual per cent change (cAPC), under the assumption of a constant rate of change. When this assumption does not hold over the entire time interval, the trend may be characterized using the annual per cent changes from segmented analysis (sAPCs). This approach assumes that the change in rates is constant over each time partition defined by the transition points, but varies among different time partitions. Different groups (e.g. racial subgroups), however, may have different transition points and thus different time partitions over which they have constant rates of change, making comparison of sAPCs problematic across groups over a common time interval of interest (e.g. the past 10 years). We propose a new measure, the average annual per cent change (AAPC), which uses sAPCs to summarize and compare trends for a specific time period. The advantage of the proposed AAPC is that it takes into account the trend transitions, whereas cAPC does not and can lead to erroneous conclusions. In addition, when the trend is constant over the entire time interval of interest, the AAPC has the advantage of reducing to both cAPC and sAPC. Moreover...

Annual World Bank Conference On Development Economics 2006 : Growth and Integration

Bourguignon, François; Pleskovic, Boris
Fonte: Washington, DC: World Bank Publicador: Washington, DC: World Bank
Português
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45.95%
The Annual World Bank Conference on Development Economics (ABCDE) brings together the world s leading scholars and development practitioners for a lively debate on state-of-the-art thinking in development policy and the implications for the global economy. The 17th conference was held in Dakar, Senegal, on January 27, 2005. The theme of the conference was growth and integration, which was divided into five topics: growth and integration, financial reforms, economic development, trade and development, and investment climate.

Economics of Adaptation to Climate Change : Samoa

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Português
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36.11%
Over the last two decades Samoa has suffered major damage from two cyclones in 1990-91, minor damage from a third cyclone in 2004, and an earthquake tsunami in 2009. Changes in the scale and impact of these types of natural disasters are likely to be important consequences of climate change for the country because the increases in sea level and in average sea surface temperatures will increase theintensity and damage from major storms. Other potential impacts are linked to changes in the weather patterns associated with El Niño Southern Oscillation (ENSO) events. The primary concern focuses on the impact on agriculture, especially in periods of lower precipitation following strong El Niño episodes.This study examines the consequences of an increase in average temperatures of up to 1°C by 2050 and up to 2.75°C by 2100 for the frequency and intensity of major cyclones that hit the islands. Estimates of the economic damage caused by storms in the past have been used to calibrate a damage function that yields an estimated increase in the expected value of economic damage as the peak wind speeds for storms with return periods of 10...

When Is Growth Pro-Poor? Cross-Country Evidence

Kraay, Aart
Fonte: World Bank, Washington, D.C. Publicador: World Bank, Washington, D.C.
Português
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36.24%
Growth is pro-poor if the poverty measure of interest falls. According to this definition there are three potential sources of pro-poor growth: (1) a high rate of growth of average incomes; (2) a high sensitivity of poverty to growth in average incomes; and (3) a poverty-reducing pattern of growth in relative incomes. The author empirically decomposes changes in poverty in a large sample of developing countries during the 1980s and 1990s into these three components. In the medium to long run, most of the variation in changes in poverty can be attributed to growth in average incomes, suggesting that policies and institutions that promote broad-based growth should be central to the pro-poor growth agenda. Most of the remainder of the variation in poverty is due to poverty-reducing patterns of growth in relative incomes, rather than differences in the sensitivity of poverty to growth in average incomes. Cross-country evidence provides relatively little guidance as to the policies and institutions that promote these other sources of pro-poor growth.

Growth Still Is Good for the Poor

Dollar, David; Kleineberg, Tatjana; Kraay, Aart
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Português
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36.25%
Incomes in the poorest two quintiles on average increase at the same rate as overall average incomes. This is because, in a global dataset spanning 118 countries over the past four decades, changes in the share of income of the poorest quintiles are generally small and uncorrelated with changes in average income. The variation in changes in quintile shares is also small relative to the variation in growth in average incomes, implying that the latter accounts for most of the variation in income growth in the poorest quintiles. These findings hold across most regions and time periods and when conditioning on a variety of country-level factors that may matter for growth and inequality changes. This evidence confirms the central importance of economic growth for poverty reduction and illustrates the difficulty of identifying specific macroeconomic policies that are significantly associated with the relative growth rates of those in the poorest quintiles.

Exporter Dynamics, Firm Size and Growth, and Partial Year Effects

Bernard, Andrew B.; Massari, Renzo; Reyes, Jose-Daniel; Taglioni, Daria
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Português
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36.23%
Two otherwise identical firms that enter the same market in different months, one in January and one in December, will report dramatically different annual sales for the first calendar year of operations. This partial year effect in annual data leads to downward biased observations of the level of activity upon entry and upward biased growth rates between the year of entry and the following year. This paper examines the implications of partial year effects using Peruvian export data. The partial year bias is very large: the average level of first-year exports of new exporters is understated by 65 percent and the average growth rate between the first and second year of exporting is overstated by 112 percentage points. This paper re-examines a number of stylized facts about firm size and growth that have motivated rapidly expanding theoretical and empirical literatures on firm export dynamics. Correcting the partial year effect eliminates unusually high growth rates in the first year of exporting, raises initial export levels...

Growth is Good for the Poor

Dollar, David; Kraay, Aart
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Português
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36.21%
When average income rises, the average incomes of the poorest fifth of society rise proportionately. This is a consequence of the strong empirical regularity that the share of income accruing to the bottom quintile does not vary systematically with average income. The authors document this empirical regularity in a sample of 92 countries spanning the past four decades and show that it holds across regions, periods, income levels, and growth rates. The authors next ask whether the factors that explain cross-country differences in the growth rates of average incomes have differential effects on the poorest fifth of society. They find that several determinants of growth--such as good rule of law, opennness to international trade, and developed financial markets--have little systematic effect on the share of income that accrues to the bottom quintile. Consequently, these factors benefit the poorest fifth of society as much as everyone else. Thee is some weak evidence that stabilization from high inflation and reductions in the overall size of government not only increase growth but also increase the income share of the poorest fifth in society. Finally...

Growth, Inequality, and Social Welfare : Cross-Country Evidence

Dollar, David; Kleineberg, Tatjana; Kraay, Aart
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Português
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36.25%
Social welfare functions that assign weights to individuals based on their income levels can be used to document the relative importance of growth and inequality changes for changes in social welfare. In a large panel of industrial and developing countries over the past 40 years, most of the cross-country and over-time variation in changes in social welfare is due to changes in average incomes. In contrast, the changes in inequality observed during this period are on average much smaller than changes in average incomes, are uncorrelated with changes in average incomes, and have contributed relatively little to changes in social welfare.

The Effect of Aid on Growth : Evidence from a Quasi-Experiment

Galiani, Sebastian; Knack, Stephen; Xu, Lixin Colin; Zou, Ben
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Português
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36.2%
The literature on aid and growth has not found a convincing instrumental variable to identify the causal effects of aid. This paper exploits an instrumental variable based on the fact that since 1987, eligibility for aid from the International Development Association (IDA) has been based partly on whether or not a country is below a certain threshold of per capita income. The paper finds evidence that other donors tend to reinforce rather than compensate for reductions in IDA aid following threshold crossings. Overall, aid as a share of gross national income (GNI) drops about 59 percent on average after countries cross the threshold. Focusing on the 35 countries that have crossed the income threshold from below between 1987 and 2010, a positive, statistically significant, and economically sizable effect of aid on growth is found. A one percentage point increase in the aid to GNI ratio from the sample mean raises annual real per capita growth in gross domestic product by approximately 0.35 percentage points. The analysis shows that the main channel through which aid promotes growth is by increasing physical investment.

Improved Annual Average Daily Traffic (AADT) Estimation for Local Roads using Parcel-Level Travel Demand Modeling

Wang, Tao
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica Formato: application/pdf
Português
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36.16%
Annual Average Daily Traffic (AADT) is a critical input to many transportation analyses. By definition, AADT is the average 24-hour volume at a highway location over a full year. Traditionally, AADT is estimated using a mix of permanent and temporary traffic counts. Because field collection of traffic counts is expensive, it is usually done for only the major roads, thus leaving most of the local roads without any AADT information. However, AADTs are needed for local roads for many applications. For example, AADTs are used by state Departments of Transportation (DOTs) to calculate the crash rates of all local roads in order to identify the top five percent of hazardous locations for annual reporting to the U.S. DOT. This dissertation develops a new method for estimating AADTs for local roads using travel demand modeling. A major component of the new method involves a parcel-level trip generation model that estimates the trips generated by each parcel. The model uses the tax parcel data together with the trip generation rates and equations provided by the ITE Trip Generation Report. The generated trips are then distributed to existing traffic count sites using a parcel-level trip distribution gravity model. The all-or-nothing assignment method is then used to assign the trips onto the roadway network to estimate the final AADTs. The entire process was implemented in the Cube demand modeling system with extensive spatial data processing using ArcGIS. To evaluate the performance of the new method...

Growth Trends in the Developing World : Country Forecasts and Determinants

Ianchovichina, Elena; Kacker, Pooja
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
Português
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46.17%
The authors present real per capita GDP growth forecasts for all developing countries for the period 2005-14. For 55 of these countries, representing major world regions and accounting for close to 80 percent of the developing world's GDP, they forecast the growth effects of the main forces underpinning growth, assuming that these evolve following past trends. The authors find that for the average developing country the largest growth dividend comes from continued improvement in public infrastructure, followed by the growth contributions of rising secondary school enrollment, trade openness, and financial deepening. The joint contribution of these four growth determinants to average, annual per capita GDP growth in the next decade is estimated to be 1 percentage point. Failure to keep improving public infrastructure alone could reduce this growth dividend by 50 percent. The forecasted growth contributions differ by country qualitatively and quantitatively.

Markups, Returns to Scale, and Productivity: A Case Study of Singapore's Manufacturing Sector

Kee, Hiau Looi
Fonte: World Bank, Washington, D.C. Publicador: World Bank, Washington, D.C.
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
Português
Relevância na Pesquisa
36.17%
The results of this paper challenge the conventional wisdom in the literature that productivity plays no role in the economic development of Singapore. Properly accounting for market power and returns to scale technology, the estimated average productivity growth is twice as large as the conventional total factor productivity (TFP) measures. Using a standard growth accounting (production function) technique, Young (1992, 1995) found no sign of TFP growth in the aggregate economy and the manufacturing sector of Singapore. Based on Young's results, Krugman (1994) claimed that there was no East Asia miracle as all the economic growth in Singapore could be attributed to its capital accumulation in the past three decades. Citing evidence on nondiminishing market rates of return to capital investment in Singapore during the period of fast growth as an indication of high productivity growth, Hsieh (1999) challenged Young's findings using the dual approach. But all of these papers maintained the assumptions of perfect competition and constant returns to scale and used only aggregate macro-level data. Kee uses industry level data and focuses on Singapore's manufacturing sector. She develops an empirical methodology to estimate industry productivity growth in the presence of market power and nonconstant returns to scale. The estimation of industry markups and returns to scale in this paper combines both the production function (primal) and the cost function (dual) approaches while controlling for input endogeneity and selection bias. The results of a fixed effect panel regression show that all industries in the manufacturing sector violate at least one of the two assumptions. Relaxing the assumptions leads to an estimated productivity growth that is on average twice as large as the conventional TFP calculation. Kee concludes that productivity growth plays a nontrivial role in the manufacturing sector.

Developing Rainfall-Based Index Insurance in Morocco

Skees, Jerry; Gober, Stephanie; Varangis, Panos; Lester, Rodney; Kalavakonda, Vijay
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
Português
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46.02%
Cereal production accounts for about seventy percent of all agricultural land in Morocco. Cereal producer prices, influenced by the government, are higher than world prices. Production is divided into six broad agro-climatic zones. About half of cereal production is concentrated in the favorable, and intermediate zones; the rest occurs mostly in less favorable (arid and semi-arid) zones, with average annual rainfall below 450 millimeters. The authors assess the feasibility of rainfall-based index insurance, to provide effective, low-cost drought insurance for Moroccan farmers, and rural dwellers. Their analysis focuses on Morocco's three main cereal crops - hard wheat, soft wheat, and barley - using data on annual production, and planting from 1978-99. Maize is included in some of the analysis. The benefits of this program over the traditional insurance scheme are that it minimizes the risk of moral hazard, and adverse selection, and promotes a streamlined pay-out-process. These features make the program more attractive to international re-insurers...

Measuring Economic Downside Risk and Severity : Growth at Risk

Wang, Yan; Yao, Yudong
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
Português
Relevância na Pesquisa
36.18%
Output collapses, and crises are a fact of life. Severe economic downturns occur periodically, and have grave consequences on the poor. The authors propose a new measurement for economic downside risk, and severity: Growth at risk. Similar to the concept of Value at Risk in finance, Growth at Risk summarizes the expected maximum economic downturn over a target horizon at a given confidence level. After providing a taxonomy of growth risks, the authors construct a panel data, set on Growth at Risk for 84 countries, over the period 1980-98. On average, different regional groups experience very distinct Growth at Risk patterns over time. 1) Non-OECD countries experience a higher downturn risk, while OECD countries' downturn risks for both big, and small recessions are the lowest among all groups. 2) East Asia countries, which had been growing faster, had a high Growth at Risk for big downturns, at around six percent, and it rose dramatically at the end of the 1990s. 3) Latin America, and Sub-Saharan Africa also maintained high Growth at Risk for both big...

Trade, Capital Accumulation, and Structural Unemployment: An Empirical Study of the Singapore Economy

Looi Kee, Hiau; Teck Hoon, Hian
Fonte: World Bank, Washington, D.C. Publicador: World Bank, Washington, D.C.
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
Português
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45.94%
The past three and a half decades witnessed a distinctly declining trend in Singapore's unemployment rate, which dropped from an average annual rate of 7.85 percent in 1966-70 to 2.74 percent in 1991-2000. The authors seek to identify and empirically examine the factors that have influenced Singapore's unemployment rate in an environment of low and stable inflation. They incorporate a union bargaining framework into a standard-factors trade model, in which an increase in the relative price or capital stock in the export sector raises the demand wage that firms can afford to pay relative to workers' fall-back income, and consequently lowers equilibrium unemployment. The magnitude of the effects depends on the fall-back income, the weight unions attach to employment, and the elasticity of labor demand, which the authors estimate using data on Singapore. The results show that labor unions in Singapore care more about employment than wages. Together with a small fall-back income and elastic labor demand, the authors show that given the same percentage change in relative export prices and capital accumulation in the export sector...

China's Growth and Poverty Reduction : Trends between 1990 and 1999

Chen, Shaohua; Wang, Yan
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
Português
Relevância na Pesquisa
36.21%
The authors investigate recent rends in poverty, and inequality in China, decomposing data on poverty reduction to see who has benefited most from China's economic growth. They find that, by several measures, poverty declined significantly in the 1990s, across a wide range of poverty lines, except that a slight slowdown in China's export, and economic growth in 1997-99 might have hurt the poor. There was a slight increase in the poverty headcount between 1997 and 1999, using lower poverty lines, and a worsening of the poverty gap index. Average per capita consumption declined for farmers, especially those living in poor regions such as Gans, Heilongjiang, Sanxi, and Xinjiang. It is unclear whether this decline was attributable to Asia's economic crisis. Economic growth contributed significantly to poverty reduction, but rising inequality worsened both rural, and urban income distributions - except during the Asian crisis, when the distribution remained relatively stable. The poor benefited far less than the rich from economic growth. Income growth reached...

Spatial analysis of annual air pollution exposure and mortality

Scoggins, Amanda; Kjellstrom, Tord; Fisher, Gavin; Connor, Jennie; Gimson, Neil
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Português
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36.16%
The aim of this study was to relate ambient air pollution levels to mortality in Auckland, New Zealand. We used urban airshed modelling and GIS-based techniques to quantify long-term exposure to ambient air pollution levels and associated mortality. After adjusting for age, sex, ethnicity, socio-economic status, and urban/rural domicile there was a 1.3% (95%CI: 1-1.5%) increase in non-external cause mortality, and 1.8% (95%CI: 1.5-2.1%) increase in circulatory and respiratory causes per 1 μg/m3 increase in annual average NO2. Based on these exposure-response relationships and applying an annual average threshold of 13 μg/m3, the average annual (for 1996-1999) number of people estimated to die from non-external causes and circulatory and respiratory causes attributable to air pollution in Auckland is 268 (95% range: 227-310) (3.9% of total all cause deaths) and 203 (95% range: 169-237) (5.9% of total circulatory and respiratory deaths) per year, respectively. The number of attributable deaths found in this study are consistent with a previous New Zealand risk assessment using a different methodology, and is approximately twice the number of people dying from motor vehicle accidents in the region, which is on average (1996-1999) 103 per year. The GIS-based exposure maps identify high exposure areas for policy developers and planners in a simple and realistic manner. Taken together with overseas studies the study provides additional evidence that long-term exposure to poor air quality...

Effect of land area on average annual suburban water demand

Jacobs,Heinz Erasmus; Scheepers,Hester Maria; Sinske,Stefan Andreas
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2013 Português
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46.04%
Current guidelines for estimating the average annual residential water demand (AADD) in South Africa are based on residential plot size. This paper presents a novel, robust method for estimating suburban water demand as a function of the suburb area. Seventy suburbs, identified as being predominantly residential, were selected for analysis from the largest urban metropolitan area in South Africa. A linear relationship was noted between the total suburb water demand and two land cover areas, namely, the total suburb area and total residential plot area. The average demand for the 70 suburbs based on suburb area was 6.6 kℓ.-d-1.ha-1, with 90% of the values in the range between 4.4 kℓ.d-1.ha-1 and 8.7 kℓ.d-1.ha-1. The average demand was 10.4 kℓ.d-1.ha-1 for calculation based on the residential area. The results are useful when crude estimates of AADD are required for planning new land developments.