Entrepreneurship and election timing

Mestrado em FinançasO objetivo desta dissertação é examinar o impacto das eleições políticas na atividade empresarial. Para isso, coletamos dados de 16 países por um número variado de anos (dentro de uma faixa de 16 a 21 anos por país) para construir uma amostra de 3.056 observações. Os nossos dados vêm do Global Entrepreneurship Monitor Adult Population Survey e do Nordsieck, W. (1997) Parties and Elections in Europe, obtido em http://www.parties-and-elections.eu. Em seguida, estimamos um pooled Ordinary Least Squares (OLS) e um modelo de efeito fixo para ver como o momento das eleições afeta os níveis empresariais no país. Além disso, examinamos os efeitos de uma vitória inesperada. Os resultados obtidos sugerem que a Atividade Empreendedora Total aumenta durante um ano eleitoral e diminui no ano anterior, enquanto não há evidência estatística de qualquer efeito no ano seguinte.Purpose of this dissertation is to examine the impact of political elections on entrepreneurial activity. In order to do so, we collect data from 17 countries for a varied number of years (within a range of 16 to 21 years per country) to build a sample of 3,056 observations. Our data comes from the Global Entrepreneurship Monitor Adult Population Survey and from Nordsieck, W. (1997) Parties and Elections in Europe retrieved from http://www.parties-and-elections.eu . We then estimate a pooled Ordinary Least Squares (OLS) and a fixed effect model to see how the elections timing affect entrepreneurial levels in the country. In addition, we examine the effects of an unexpected victory, Results obtained suggest that Total Entrepreneurial Activity increases during an election year and decreases the year before, while there is no statistical evidence of any effect in the year after.info:eu-repo/semantics/publishedVersio

Electromagnetic tunneling through a single-negative slab paired with a double-positive bi-layer

We show that resonant tunneling of electromagnetic fields can occur through a three-layer structure composed of a single-negative (i.e., either negative-permittivity or negative-permeability) slab paired with bi-layer made of double-positive (i.e., positive permittivity and permeability) media. In particular, one of the two double-positive media can be chosen arbitrarily (even vacuum), while the other may exhibit extreme (either near-zero or very high) permittivity/permeability values. Our results on this counterintuitive tunneling phenomenon also demonstrate the possibility of synthesizing double-positive slabs that effectively exhibit single-negative-like wave-impedance properties within a moderately wide frequency range.Comment: 5 pages, 5 figures (minor revisions

Experimental evidence of guided resonances in photonic crystals with aperiodically-ordered supercells

We report on the first experimental evidence of guided resonances (GRs) in photonic crystal slabs based on aperiodically-ordered supercells. Using the Ammann-Beenker (quasiperiodic, 8-fold symmetric) tiling geometry, we present our study on the fabrication, experimental characterization, and full-wave numerical simulation of two representative structures (with different filling parameters) operating at near-infrared wavelengths (1300-1600 nm). Our results show a fairly good agreement between measurements and numerical predictions, and pave the way for the development of new strategies (based, e.g., on the lattice symmetry breaking) for GR engineering.Comment: 10 pages, 5 figures (minor revisions