2,179 research outputs found
Does conditionality matter for adults' health? Evidence from a randomized experiment
We present evidence on how the requirement to attend health and nutrition sessions affetcs the health behaviour of adults living in households targeted by a nutritional programme in rural Mexico. The evaluation sample of the Programa de Apoyo Alimentario (PAL) is unique in having four different treatment types, which are randomly assigned to four different groups of localities, which one group designed to receive tranfers but without any requirement to attend health and nutrition courses. We find that attendance at educational sessions does not affect drinking and smoking behaviour, but significantly reduces the probability of having a large waist circumference among women. We provide evidence that attending health and nutrition related courses determines a large drop in the probability that adult women have excessive calorie intake. The results suggest that lack of information can explain, at least in part, the impressive rise in female obesity in developing countries
Diamonds of finite type in thin Lie algebras
Borrowing some terminology from pro-p groups, thin Lie algebras are N-graded
Lie algebras of width two and obliquity zero, generated in degree one. In
particular, their homogeneous components have degree one or two, and they are
termed diamonds in the latter case. In one of the two main subclasses of thin
Lie algebras the earliest diamond after that in degree one occurs in degree
2q-1, where q is a power of the characteristic. This paper is a contribution to
a classification project of this subclass of thin Lie algebras. Specifically,
we prove that, under certain technical assumptions, the degree of the earliest
diamond of finite type in such a Lie algebra can only have a certain form,
which does occur in explicit examples constructed elsewhere.Comment: 19 page
Nottingham Lie algebras with diamonds of finite and infinite type
We consider a class of infinite-dimensional, modular, graded Lie algebras,
which includes the graded Lie algebra associated to the Nottingham group with
respect to its lower central series. We identify two subclasses of Nottingham
Lie algebras as loop algebras of finite-dimensional simple Lie algebras of
Hamiltonian Cartan type. A property of Laguerre polynomials of derivations,
which is related to toral switching, plays a crucial role in our constructions.Comment: 17 pages; minor changes from the previous versio
Snakes and ladders in an inhomogeneous neural field model
Continuous neural field models with inhomogeneous synaptic connectivities are
known to support traveling fronts as well as stable bumps of localized
activity. We analyze stationary localized structures in a neural field model
with periodic modulation of the synaptic connectivity kernel and find that they
are arranged in a snakes-and-ladders bifurcation structure. In the case of
Heaviside firing rates, we construct analytically symmetric and asymmetric
states and hence derive closed-form expressions for the corresponding
bifurcation diagrams. We show that the ideas proposed by Beck and co-workers to
analyze snaking solutions to the Swift-Hohenberg equation remain valid for the
neural field model, even though the corresponding spatial-dynamical formulation
is non-autonomous. We investigate how the modulation amplitude affects the
bifurcation structure and compare numerical calculations for steep sigmoidal
firing rates with analytic predictions valid in the Heaviside limit
Screening tests, information, and the health-education gradient
The association between health outcomes and education - the health-education gradient - is widely documented but little is known about its source. Using microeconomic data on a sample of individuals aged 50+ in eight European countries, we find that education and cognitive skills (such as verbal fluency) are associated with a greater propensity for standard screening tests (mammography and colonoscopy). In order to study the role of information on the decision to screen, we test whether the health-education gradient varies with the quality of the information provided by the health care system, as proxied by the quality of the General Practitioner. Using an Instrumental Variable approach to control for the potential endogeneity of the GP quality score, we find evidence of a strong and significant complementarity between education and quality of primary care. We interpret this result as evidence that health-education gradient can be explained, at least in part, by the fact that better educated individuals are more able to process and internalize health related information as provided by GPs
Noise reduction in coarse bifurcation analysis of stochastic agent-based models: an example of consumer lock-in
We investigate coarse equilibrium states of a fine-scale, stochastic
agent-based model of consumer lock-in in a duopolistic market. In the model,
agents decide on their next purchase based on a combination of their personal
preference and their neighbours' opinions. For agents with independent
identically-distributed parameters and all-to-all coupling, we derive an
analytic approximate coarse evolution-map for the expected average purchase. We
then study the emergence of coarse fronts when spatial segregation is present
in the relative perceived quality of products. We develop a novel Newton-Krylov
method that is able to compute accurately and efficiently coarse fixed points
when the underlying fine-scale dynamics is stochastic. The main novelty of the
algorithm is in the elimination of the noise that is generated when estimating
Jacobian-vector products using time-integration of perturbed initial
conditions. We present numerical results that demonstrate the convergence
properties of the numerical method, and use the method to show that macroscopic
fronts in this model destabilise at a coarse symmetry-breaking bifurcation.Comment: This version of the manuscript was accepted for publication on SIAD
Screening Tests, Information, and the Health-Education Gradient
The association between health outcomes and education – the health-education gradient - is widely documented but little is known about its source. Using microeconomic data on a sample of individuals aged 50+ in eight European countries, we find that education and cognitive skills (such as verbal fluency) are associated with a greater propensity for standard screening tests (mammography and colonoscopy). In order to study the role of information on the decision to screen, we test whether the health-education gradient varies with the quality of the information provided by the health care system, as proxied by the quality of the General Practitioner. Using an Instrumental Variable approach to control for the potential endogeneity of the GP quality score, we find evidence of a strong and significant complementarity between education and quality of primary care. We interpret this result as evidence that health-education gradient can be explained, at least in part, by the fact that better educated individuals are more able to process and internalize health related information as provided by GPs.Health, education, information, general practitioners
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