Measuring welfare for small but vulnerable groups poverty and disabiity in Uganda

When vulnerable population groups are numerically small -as is often the case, obtaining representative welfare estimates from non-purposive sample surveys becomes an issue. Building on a method developed by Elbers, Lanjouw and Lanjouw (2003) it is shown how, for census years, estimates of income poverty for small vulnerable populations can be derived by combining sample survey and population census information. The approach is illustrated for Uganda, for which poverty amongst households with disabled heads is determined. This is possibly the first time that, for a developing country, statistically representative information on income poverty amongst disabled people is generated.Poverty Assessment,VN-Acb Mis -- IFC-00535908,Health Monitoring&Evaluation,Health Economics&Finance,Social Protections&Assistance

Not Separate, Not Equal: Poverty and Inequality in Post-Apartheid South Africa

As South Africa conducts a review of the first ten years of its new democracy, the question remains as to whether the economic inequalities of the apartheid era are beginning to fade. Using new, comparable consumption aggregates for 1995 and 2000, this paper finds that real per capita household expenditures declined for those at the bottom end of the expenditure distribution during this period of low GDP growth. As a result, poverty, especially extreme poverty, increased. Inequality also increased, mainly due to a jump in inequality among the African population. Even among subgroups of the population that experienced healthy consumption growth, such as the Coloureds, the rate of poverty reduction was low because the distributional shifts were not pro-poor.http://deepblue.lib.umich.edu/bitstream/2027.42/40125/3/wp739.pd

The effect of deuteriation on the emission lifetime of inorganic compounds

The application of deuteriation of both ligands and solvents on the photophysical properties of transition metal complexes in solution and glassy matrices is reviewed. The reduction in amplitude and frequency of vibrational modes due to deuterium's increased mass, relative to hydrogen, has a significant effect on non-radiative deactivation processes, which can occur through both intra- and inter-molecular vibrational coupling. The effect of deuteriation on excited state lifetimes has allowed for its application in probing the nature of excited state decay processes. The effects of isotopic exchange on vibrational spectroscopies such as resonance Raman and low temperature high-resolution emission spectroscopies are also addressed briefly

Achievable Outage Rate Regions for the MISO Interference Channel

We consider the slow-fading two-user multiple-input single-output (MISO) interference channel. We want to understand which rate points can be achieved, allowing a non-zero outage probability. We do so by defining four different outage rate regions. The definitions differ on whether the rates are declared in outage jointly or individually and whether the transmitters have instantaneous or statistical channel state information (CSI). The focus is on the instantaneous CSI case with individual outage, where we propose a stochastic mapping from the rate point and the channel realization to the beamforming vectors. A major contribution is that we prove that the stochastic component of this mapping is independent of the actual channel realization.Comment: Accepted for publication in IEEE Wireless Communications Letter

Efficient Computation of Pareto Optimal Beamforming Vectors for the MISO Interference Channel with Successive Interference Cancellation

We study the two-user multiple-input single-output (MISO) Gaussian interference channel where the transmitters have perfect channel state information and employ single-stream beamforming. The receivers are capable of performing successive interference cancellation, so when the interfering signal is strong enough, it can be decoded, treating the desired signal as noise, and subtracted from the received signal, before the desired signal is decoded. We propose efficient methods to compute the Pareto-optimal rate points and corresponding beamforming vector pairs, by maximizing the rate of one link given the rate of the other link. We do so by splitting the original problem into four subproblems corresponding to the combinations of the receivers' decoding strategies - either decode the interference or treat it as additive noise. We utilize recently proposed parameterizations of the optimal beamforming vectors to equivalently reformulate each subproblem as a quasi-concave problem, which we solve very efficiently either analytically or via scalar numerical optimization. The computational complexity of the proposed methods is several orders-of-magnitude less than the complexity of the state-of-the-art methods. We use the proposed methods to illustrate the effect of the strength and spatial correlation of the channels on the shape of the rate region.Comment: Accepted for publication in IEEE Transactions on Signal Processin

Gradual Program Analysis

Dataflow analysis and gradual typing are both well-studied methods to gain information about computer programs in a finite amount of time. The gradual program analysis project seeks to combine those two techniques in order to gain the benefits of both. This thesis explores the background information necessary to understand gradual program analysis, and then briefly discusses the research itself, with reference to publication of work done so far. The background topics include essential aspects of programming language theory, such as syntax, semantics, and static typing; dataflow analysis concepts, such as abstract interpretation, semilattices, and fixpoint computations; and gradual typing theory, such as the concept of an unknown type, liftings of predicates, and liftings of functions

Adaptation in tunably rugged fitness landscapes: The Rough Mount Fuji Model

Much of the current theory of adaptation is based on Gillespie's mutational landscape model (MLM), which assumes that the fitness values of genotypes linked by single mutational steps are independent random variables. On the other hand, a growing body of empirical evidence shows that real fitness landscapes, while possessing a considerable amount of ruggedness, are smoother than predicted by the MLM. In the present article we propose and analyse a simple fitness landscape model with tunable ruggedness based on the Rough Mount Fuji (RMF) model originally introduced by Aita et al. [Biopolymers 54:64-79 (2000)] in the context of protein evolution. We provide a comprehensive collection of results pertaining to the topographical structure of RMF landscapes, including explicit formulae for the expected number of local fitness maxima, the location of the global peak, and the fitness correlation function. The statistics of single and multiple adaptive steps on the RMF landscape are explored mainly through simulations, and the results are compared to the known behavior in the MLM model. Finally, we show that the RMF model can explain the large number of second-step mutations observed on a highly-fit first step backgound in a recent evolution experiment with a microvirid bacteriophage [Miller et al., Genetics 187:185-202 (2011)].Comment: 43 pages, 12 figures; revised version with new results on the number of fitness maxim

On tree-decompositions of one-ended graphs

A graph is one-ended if it contains a ray (a one way infinite path) and whenever we remove a finite number of vertices from the graph then what remains has only one component which contains rays. A vertex $v$ {\em dominates} a ray in the end if there are infinitely many paths connecting $v$ to the ray such that any two of these paths have only the vertex $v$ in common. We prove that if a one-ended graph contains no ray which is dominated by a vertex and no infinite family of pairwise disjoint rays, then it has a tree-decomposition such that the decomposition tree is one-ended and the tree-decomposition is invariant under the group of automorphisms. This can be applied to prove a conjecture of Halin from 2000 that the automorphism group of such a graph cannot be countably infinite and solves a recent problem of Boutin and Imrich. Furthermore, it implies that every transitive one-ended graph contains an infinite family of pairwise disjoint rays