Nonparametric models of financial leverage decisions

This paper investigates the properties of nonparametric decision tree models in the analysis of financial leverage decisions. This approach presents two appealing features: the relationship between leverage ratios and the explanatory variables is not predetermined but is derived according to information provided by the data, and the models respect the bounded and fractional nature of leverage ratios. The analysis shows that tree models suggest relationships between explanatory variables and the relative amount of issued debt that parametric models fail to capture. Furthermore, the significant relationships found by tree models are in most cases in accordance with the effects predicted by the pecking-order theory. The results also show that two-part tree models can accommodate better the distinct effects of explanatory variables on the decision to issue debt and on the amount of debt issued by firms that do resort to debt.Capital structure, Fractional regression, Decision trees, Two-part models

Vacuum decay in an interacting multiverse

We examine a new multiverse scenario in which the component universes interact. We focus our attention to the process of "true" vacuum nucleation in the false vacuum within one single element of the multiverse. It is shown that the interactions lead to a collective behaviour that might lead, under specific conditions, to a pre-inflationary phase and ensued distinguishable imprints in the comic microwave background radiation.Comment: 9 pages, 5 figure

A Multivariate Training Technique with Event Reweighting

An event reweighting technique incorporated in multivariate training algorithm has been developed and tested using the Artificial Neural Networks (ANN) and Boosted Decision Trees (BDT). The event reweighting training are compared to that of the conventional equal event weighting based on the ANN and the BDT performance. The comparison is performed in the context of the physics analysis of the ATLAS experiment at the Large Hadron Collider (LHC), which will explore the fundamental nature of matter and the basic forces that shape our universe. We demonstrate that the event reweighting technique provides an unbiased method of multivariate training for event pattern recognition.Comment: 20 pages, 8 figure

Boletim agrometeorológico de 2009 para o Município de Teresina, PI.

Neste boletim, são apresentados valores diários de temperatura do ar (média, máxima e mínima), umidade relativa do ar, velocidade do vento corrigida para 2 m de altura, insolação, evapotranspiração de referência, precipitação pluviométrica e pressão atmosférica referentes ao ano de 2009. Também são apresentadas, graficamente, as normais climatológicas referentes aos anos de 1980 a 2008 e o balanço hídrico climatológico de 2009.bitstream/item/83439/1/Doc-206-Boletim-agrometeorologico-the-2009.pd

Boletim agrometeorológico de 2007 para o Município de Teresina, Piauí.

bitstream/item/87996/1/DOC1810001.pd

Boletim Agrometeorológico de 2010 para o Município de Teresina, Piauí.

Neste boletim, são apresentados valores diários de temperatura do ar (média, máxima e mínima), umidade relativa do ar, velocidade do vento corrigida para 2 m de altura, insolação, evapotranspiração de referência, precipitação pluviométrica e pressão atmosférica referentes ao ano de 2010. Também são apresentadas, graficamente, as normais climatológicas referentes aos anos de 1980 a 2009 e o balanço hídrico climatológico de 2010.bitstream/item/83453/1/Doc-210-Boletim-agrometeorologico-the-2010.pd

Boletim agrometeorológico de 2008 para o Município de Teresina, PI.

bitstream/item/80704/1/documento-200.pd

Metodologia para simulação de elementos climáticos em planilha eletrônica.

Metodologia; Teste de aderência; Simulação da precipitação; Simulação da evapotranspiração de referência.bitstream/item/35874/1/Doc68.pd

Basin structure in the two-dimensional dissipative circle map

Fractal basin structure in the two-dimensional dissipative circle map is examined in detail. Numerically obtained basin appears to be riddling in the parameter region where two periodic orbits co-exist near a boundary crisis, but it is shown to consist of layers of thin bands.Comment: published in J. Phys. Soc. Jpn., 72, 1943-1947 (2003