Bank Efficiency and Default in Brazil: Causality Tests

Periods of Financial Stability are associated to low bank efficiency and high non-performing loans in credit portfolios. Therefore, this paper studies the relationship between bank efficiency and non-performing loans. To evaluate the bank efficiency, we employ a Data Envelopment Analysis. We employ the Arelano-Bond dynamic panel approach and a panel-VAR to test whether non-performing loans Granger cause bank efficiency (bad luck hypothesis) or whether bank efficiency affects loan quality (management with risk aversion). Empirical results for the Brazilian case corroborate the second hypothesis.

Myopic Loss Aversion and House-Money Effect Overseas: an experimental approach

Recent literature has found two behavioral effects - house-money and myopic loss aversion (MLA) - in several experimental designs. We show that although we can find a house-money effect using survey methods this evidence disappears when we study investment decision within a multi-period investment experiment. Loss aversion is found to govern the risk-taking behavior of subjects in dynamic settings, overcoming the house-money effect. These results are robust to experiments conducted in two different countries, Spain and Brazil.

Tracking system study

A digital computer program was generated which mathematically describes an optimal estimator-controller technique as applied to the control of antenna tracking systems used by NASA. Simulation studies utilizing this program were conducted using the IBM 360/91 computer. The basic ideas of applying optimal estimator-controller techniques to antenna tracking systems are discussed. A survey of existing tracking methods is given along with shortcomings and inherent errors. It is explained how these errors can be considerably reduced if optimal estimation and control are used. The modified programs generated in this project are described and the simulation results are summarized. The new algorithms for direct synthesis and stabilization of the systems including nonlinearities, are presented

Fast-ignition design transport studies: realistic electron source, integrated PIC-hydrodynamics, imposed magnetic fields

Transport modeling of idealized, cone-guided fast ignition targets indicates the severe challenge posed by fast-electron source divergence. The hybrid particle-in-cell [PIC] code Zuma is run in tandem with the radiation-hydrodynamics code Hydra to model fast-electron propagation, fuel heating, and thermonuclear burn. The fast electron source is based on a 3D explicit-PIC laser-plasma simulation with the PSC code. This shows a quasi two-temperature energy spectrum, and a divergent angle spectrum (average velocity-space polar angle of 52 degrees). Transport simulations with the PIC-based divergence do not ignite for > 1 MJ of fast-electron energy, for a modest 70 micron standoff distance from fast-electron injection to the dense fuel. However, artificially collimating the source gives an ignition energy of 132 kJ. To mitigate the divergence, we consider imposed axial magnetic fields. Uniform fields ~50 MG are sufficient to recover the artificially collimated ignition energy. Experiments at the Omega laser facility have generated fields of this magnitude by imploding a capsule in seed fields of 50-100 kG. Such imploded fields are however more compressed in the transport region than in the laser absorption region. When fast electrons encounter increasing field strength, magnetic mirroring can reflect a substantial fraction of them and reduce coupling to the fuel. A hollow magnetic pipe, which peaks at a finite radius, is presented as one field configuration which circumvents mirroring.Comment: 16 pages, 17 figures, submitted to Phys. Plasma

Oceanic internal-wave field : theory of scale-invariant spectra

Author Posting. © American Meteorological Society, 2010. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 40 (2010): 2605–2623, doi:10.1175/2010JPO4132.1.Steady scale-invariant solutions of a kinetic equation describing the statistics of oceanic internal gravity waves based on wave turbulence theory are investigated. It is shown in the nonrotating scale-invariant limit that the collision integral in the kinetic equation diverges for almost all spectral power-law exponents. These divergences come from resonant interactions with the smallest horizontal wavenumbers and/or the largest horizontal wavenumbers with extreme scale separations. A small domain is identified in which the scale-invariant collision integral converges and numerically find a convergent power-law solution. This numerical solution is close to the Garrett–Munk spectrum. Power-law exponents that potentially permit a balance between the infrared and ultraviolet divergences are investigated. The balanced exponents are generalizations of an exact solution of the scale-invariant kinetic equation, the Pelinovsky–Raevsky spectrum. A small but finite Coriolis parameter representing the effects of rotation is introduced into the kinetic equation to determine solutions over the divergent part of the domain using rigorous asymptotic arguments. This gives rise to the induced diffusion regime. The derivation of the kinetic equation is based on an assumption of weak nonlinearity. Dominance of the nonlocal interactions puts the self-consistency of the kinetic equation at risk. However, these weakly nonlinear stationary states are consistent with much of the observational evidence.This research is supported by NSF CMG Grants 0417724, 0417732 and 0417466. YL is also supported by NSF DMS Grant 0807871 and ONR Award N00014-09-1-0515

Concentração e Inadimplência nas Carteiras de Empréstimos dos Bancos Brasileiros

This paper evaluates the loans market in Brazil in the 2003 to 2008 period. It measures diversification and nonperforming loans for Banks credit portfolios. We employ the credit risk bureau database, which classifies loans by sector and risk. Results show an increase in higher risk loans and diversification in low risk loans. The non-performing loans figures have shown a downward trend for most economic activities.

Influence of home and school environments on specific dietary behaviors among postpartum, high-risk teens, 27 states, 2007-2009

INTRODUCTION: The objective of this study was to determine whether perceptions of the home and school food environments are related to food and beverage intakes of postpartum teens. METHODS: Our study was a baseline, cross-sectional analysis of 853 postpartum teens enrolled in a weight-loss intervention study across 27 states from 2007 through 2009. Eight-item scales assessed perceived accessibility and availability of foods and beverages in school and home environments. Associations between environments and intakes were assessed by using χ(2) and using logistic regression with generalized estimating equations (GEE), respectively. RESULTS: Overall, 52% of teens perceived their school food environment as positive, and 68% of teens perceived their home food environment as positive. A positive school environment was independently associated with fruit consumption and 100% fruit juice consumption. A positive home environment was independently associated with fruit, vegetable, and water consumption and infrequent consumption of soda and chips (χ(2) P < .05). Having only a positive school environment was associated with fruit consumption (GEE odds ratio [OR], 3.1; 95% confidence interval [CI], 1.5–6.5), and having only a positive home environment was associated with fruit (GEE OR, 2.9; 95% CI, 1.6–5.6), vegetable (GEE OR, 3.1; 95% CI, 1.5–6.2), and water (GEE OR, 2.6; 95% CI, 1.7–4.0) consumption and infrequent consumption of soda (GEE OR, 0.5; 95% CI, 0.3–0.7). Results for positive home and school environments were similar to those for positive home only. CONCLUSION: Home and school environments are related to dietary behaviors among postpartum teens, with a positive home environment more strongly associated with healthful behaviors

Crystallization and preliminary structural analysis of the giant haemoglobin from Glossoscolex paulistus at 3.2 Å

Diffraction data to 3.2 Å from crystals of the 3.6 MDa erythrocruorin from a Brazilian earthworm represent the highest resolution reported to date for similar complexes. An unambiguous molecular replacement solution shows the particle to belong to the type I class

Impact of Type 2 diabetes prevention programmes based on risk identification and lifestyle intervention intensity strategies: a cost-effectiveness analysis

Aim To develop a cost-effectiveness model to compare Type 2 diabetes prevention programmes that target different at-risk population subgroups through lifestyle interventions of varying intensity. Methods An individual patient simulation model simulated the development of diabetes in a representative sample of adults without diabetes from the UK population. The model incorporates trajectories for HbA1c, 2-h glucose, fasting plasma glucose, BMI, systolic blood pressure, total cholesterol and HDL cholesterol. In the model, patients can be diagnosed with diabetes, cardiovascular disease, microvascular complications of diabetes, cancer, osteoarthritis and depression, or can die. The model collects costs and utilities over a lifetime horizon. The perspective is the UK National Health Service and Personal Social Services. We used the model to evaluate the population-wide impact of targeting a lifestyle intervention of varying intensity to six population subgroups defined as at high risk for diabetes. Results The intervention produces 0.0020 to 0.0026 incremental quality-adjusted life-years and saves £15 to £23 per person in the general population, depending on the subgroup targeted. Cost-effectiveness increases with intervention intensity. The most cost-effective options were to target South-Asian people and those with HbA1c levels > 42 mmol/mol (6%). Conclusion The model indicates that diabetes prevention interventions are likely to be cost-saving. The criteria for selecting at-risk individuals differentially has an impact on diabetes and cardiovascular disease outcomes, and on the timing of costs and benefits. The model is not currently able to account for potential differential uptake or efficacy between subgroups. These findings have implications for deciding who should be targeted for diabetes prevention interventions.NIH