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We evaluate the longer run impact of a local accountability intervention in primary health care provision in Uganda. Short-run improvements in health care delivery and health outcomes remained in the longer run despite minimal fol...
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We evaluate the longer run impact of a local accountability intervention in primary health care provision in Uganda. Short-run improvements in health care delivery and health outcomes remained in the longer run despite minimal follow-up. We find no impact on the quality of care or health outcomes of a lower cost intervention that focused on encouraging participation but did not provide information on staff performance. We provide suggestive evidence that informed beneficiaries are more likely to identify and challenge (mis)behavior by providers and. As a result, turn their focus to issues that they can manage locally.
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Smallholder farming in many developing countries is characterized by low productivity and low-quality output. Low quality limits the price farmers can command and their potential income. We conduct a series of experiments among ma...
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Smallholder farming in many developing countries is characterized by low productivity and low-quality output. Low quality limits the price farmers can command and their potential income. We conduct a series of experiments among maize farmers in Uganda to shed light on the barriers to quality upgrading and to study its potential. We find that the causal return to quality is zero. Providing access to a market where quality is paid a market premium led to an increase in farm productivity and income from farming. Our findings reveal the importance of demand-side constraints in limiting rural income and productivity growth.
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The concepts of standard analysis techniques applied in the field of Fourier spectroscopy treat fundamental aspects insufficiently. For example, the spectra to be inferred are influenced by the noise contribution to the interferom...
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The concepts of standard analysis techniques applied in the field of Fourier spectroscopy treat fundamental aspects insufficiently. For example, the spectra to be inferred are influenced by the noise contribution to the interferometric data, by nonprobed spatial domains which are linked to Fourier coefficients above a certain order, by the spectral limits which are in general not given by the Nyquist assumptions, and by additional parameters of the problem at hand like the zero-path difference. To consider these fundamentals, a probabilistic approach based on Bayes’ theorem is introduced which exploits multivariate normal distributions. For the example application, we model the spectra by the Gaussian process of a Brownian bridge stated by a prior covariance. The spectra themselves are represented by a number of parameters which map linearly to the data domain. The posterior for these linear parameters is analytically obtained, and the marginalisation over these parameters is trivial. This allows the straightforward investigation of the posterior for the involved nonlinear parameters, like the zero-path difference location and the spectral limits, and hyperparameters, like the scaling of the Gaussian process. With respect to the linear problem, this can be interpreted as an implementation of Ockham’s razor principle.
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According to official statistics, 20 percent of Uganda's total public expenditure was spent on education in the mid-1990s, most of it on primary education. One of the large public programs was a capitation grant to cover schools' ...
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According to official statistics, 20 percent of Uganda's total public expenditure was spent on education in the mid-1990s, most of it on primary education. One of the large public programs was a capitation grant to cover schools' nonwage expenditures.Using panel data from a unique survey of primary schools, we assess the extent to which the giant actually reached the intended end-user (schools). The survey data reveal that during 1991-1995, the schools, on average, received only 13 percent of the grants. Most schools received nothing. The bulk of the school grant was captured by local officials (and politicians). The data also reveal considerable variation in grants received across schools, suggesting that rather than being passive recipients of flows from the government, schools use their bargaining power to secure greater shares of funding. We find that schools in better-off communities managed to claim a higher share of their entitlements. As a result, actual education spending, in contrast tobudget allocations, is regressive. Similar surveys in other African countries confirm that Uganda is not a special case.
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Some years ago I interviewed the chief executive officer of a successful Thai manufacturing firm as part of a pilot survey project. While trying to figure out a good way to quantify the firm's experience with government regulation...
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Some years ago I interviewed the chief executive officer of a successful Thai manufacturing firm as part of a pilot survey project. While trying to figure out a good way to quantify the firm's experience with government regulations and corruption in the foreign trade sector, the CEO exclaimed: "I hope to be reborn as a custom official." When a well-paid CEO wishes for ajob with low official pay in the government sector, corruption is almost surely a problem! The most devastating forms of corruption include the diversion and outright theft of funds for public programs and the damage caused by firms and individuals that pay bribes to avoid health and safety regulations intended to benefit the public. Examples abound. A conservative estimate is that the former President of Zaire, Mobutu Sese Seko, looted the treasury of some $5 billion—an amount equal to the country's entire external debt at the time he was ousted in 1997. The funds allegedly embezzled by the former presidents of Indonesia and Philippines, Mo-hamed Suharto and Ferdinand Marcos, are estimated to be two and seven times higher (Transparency International, 2004). In the Goldenberg scam in Kenya in the early 1990s, the Goldenberg firm received as much as $1 billion from the government as part of an export compensation scheme for fictitious exports of commodities of which Kenya either produced little (gold) or nothing at all (diamonds) ("Public Inquiry into Kenya Gold Scam," 2003). An internal IMF report found that nearly $1 billion of oil revenues, or $77 per capita, vanished from Angolan state coffers in 2001 alone (Pearce, 2002).
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This paper uses a unique data set on corruption containing quantitative information on bribe payments of Ugandan firms. The data have two striking features: not all firms report that they need to pay bribes, and there is considera...
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This paper uses a unique data set on corruption containing quantitative information on bribe payments of Ugandan firms. The data have two striking features: not all firms report that they need to pay bribes, and there is considerable variation in reported graft across firms facing similar institutions/policies. We propose an explanation for these patterns, based on differences in control rights and bargaining strength across firms. Consistent with the control rights/ bargaining hypotheses, we findthat the incidence of corruption can be explained by the variation in policies/regulations across industries. How much must bribepaying firms pay? Combining the quantitative data on corruption with detailed financial information from the surveyed firms,we show that firms' "ability to pay" and firms' "refusal power" can explain a large part of the variation in bribes across graft-reporting firms. These results suggest that public officials act as price (bribe) discriminators, and that prices of public services are partly determined in order to extract bribes.
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Disbursements of foreign aid are guided (in part) by the needs of the poor. Anticipating this, recipients have little incentive to improve the welfare of the poor. In principle, conditionality could partly solve the problem, but t...
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Disbursements of foreign aid are guided (in part) by the needs of the poor. Anticipating this, recipients have little incentive to improve the welfare of the poor. In principle, conditionality could partly solve the problem, but this requires a strong commitment ability by the donor. Without such a commitment technology, aid will be allocated (partly) to those in most need, and the recipient governments will exert low effort in alleviating poverty. Contrary to conventional wisdom in the aid literature, we show that tied project aid and delegation of part of the aid budget to an (international) agency with less aversion to poverty improve welfare of the poor in the recipient countries.
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This paper studies a simple reform that introduces ex post incentives for the donor to reward good policies—contrary to existing practices. Instead of committing aid to each recipient ex ante and making aid conditional on reform,...
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This paper studies a simple reform that introduces ex post incentives for the donor to reward good policies—contrary to existing practices. Instead of committing aid to each recipient ex ante and making aid conditional on reform, the donor centralizes the disbursement decision by committing aid to a group of countries. The actual amount disbursed to each individual country would depend on its relative performance. This explicit linkage of the allocation and disbursement decisions has two importantadvantages as compared to present practices. First, it raises the opportunity cost of disbursing aid ex post, thereby giving the donor stronger incentives to reward good policies. Second, competition among recipients allows the donor to make inferences about common shocks, which otherwise conceal the recipient's choice of action. This enables the donor to give aid more efficiently.
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In magnetic confinement fusion research, the achievement of high plasma pressure is key to reaching the goal of net energy production. The magnetohydrodynamic (MHD) model is used to self-consistently calculate the effects the plas...
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In magnetic confinement fusion research, the achievement of high plasma pressure is key to reaching the goal of net energy production. The magnetohydrodynamic (MHD) model is used to self-consistently calculate the effects the plasma pressure induces on the magnetic field used to confine the plasma. Such MHD calculations-usually done computationally-serve as input for the assessment of a number of important physics questions. The variational moments equilibrium code (VMEC) is the most widely used to evaluate 3D ideal-MHD equilibria, as prominently present in stellarators. However, considering the computational cost, it is rarely used in large-scale or online applications (e.g. Bayesian scientific modeling, real-time plasma control). Access to fast MHD equilibria is a challenging problem in fusion research, one which machine learning could effectively address. In this paper, we present artificial neural network (NN) models able to quickly compute the equilibrium magnetic field of Wendelstein 7-X. Magnetic configurations that extensively cover the device operational space, and plasma profiles with volume-averaged normalized plasma pressure 〈B〉(β = (2μ_0p)/(B~2)) up to 5% and non-zero net toroidal current are included in the data set. By using convolutional layers, the spectral representation of the magnetic flux surfaces can be efficiently computed with a single network. To discover better models, a Bayesian hyper-parameter search is carried out, and 3D convolutional NNs are found to outperform feed-forward fully-connected NNs. The achieved normalized root-mean-squared error, the ratio between the regression error and the spread of the data, ranges from 1% to 20% across the different scenarios. The model inference time for a single equilibrium is on the order of milliseconds. Finally, this work shows the feasibility of a fast NN drop-in surrogate model for VMEC, and it opens up new operational scenarios where target applications could make use of magnetic equilibria at unprecedented scales.
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In magnetic confinement fusion research, the achievement of high plasma pressure is key to reaching the goal of net energy production. The magnetohydrodynamic (MHD) model is used to self-consistently calculate the effects the plas...
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In magnetic confinement fusion research, the achievement of high plasma pressure is key to reaching the goal of net energy production. The magnetohydrodynamic (MHD) model is used to self-consistently calculate the effects the plasma pressure induces on the magnetic field used to confine the plasma. Such MHD calculations—usually done computationally—serve as input for the assessment of a number of important physics questions. The variational moments equilibrium code (VMEC) is the most widely used to evaluate 3D ideal-MHD equilibria, as prominently present in stellarators. However, considering the computational cost, it is rarely used in large-scale or online applications (e.g. Bayesian scientific modeling, real-time plasma control). Access to fast MHD equilibria is a challenging problem in fusion research, one which machine learning could effectively address. In this paper, we present artificial neural network (NN) models able to quickly compute the equilibrium magnetic field of Wendelstein 7-X. Magnetic configurations that extensively cover the device operational space, and plasma profiles with volume-averaged normalized plasma pressure ? β ? ( β = frac{2{mu }_{0}p}{{B}^{2}} ) up to 5% and non-zero net toroidal current are included in the data set. By using convolutional layers, the spectral representation of the magnetic flux surfaces can be efficiently computed with a single network. To discover better models, a Bayesian hyper-parameter search is carried out, and 3D convolutional NNs are found to outperform feed-forward fully-connected NNs. The achieved normalized root-mean-squared error, the ratio between the regression error and the spread of the data, ranges from 1% to 20% across the different scenarios. The model inference time for a single equilibrium is on the order of milliseconds. Finally, this work shows the feasibility of a fast NN drop-in surrogate model for VMEC, and it opens up new operational scenarios where target applications could make use of magnetic equilibria at unprecedented scales.
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