6,648 research outputs found
Light dual multinets of order six in the projective plane
The aim of this paper is twofold: First we classify all abstract light dual
multinets of order which have a unique line of length at least two. Then we
classify the weak projective embeddings of these objects in projective planes
over fields of characteristic zero. For the latter we present a computational
algebraic method for the study of weak projective embeddings of finite
point-line incidence structures
Euro Area Inflation: Aggregation Bias and Convergence
EMU monetary policy targets aggregate Euro Area inflation. Concerns are growing that a focus on aggregate inflation may cause national inflation rates to diverge. While different explanations for diverging aggregate Euro Area inflation have been brought forward, the very impact of aggregation on divergence has however not been studied. We find a striking difference in convergence depending on the level of aggregation. While aggregate national inflation rates are diverging, disaggregate inflation rates are converging. We find that aggregation appears to bias evidence towards non-convergence. Our results are consistent with prominent theoretical and empirical evidence on aggregation biasEuro Area Inflation; Aggregation Bias; Convergence
International capital flows to emerging and developing countries: national and global determinants
This paper examines international capital flows to emerging and developing countries. We assess whether commonalities exist, the permanence of shocks to commonalities and their determinants. Also, we consider individual country coherence with global capital flows and we measure the extent of co-movements in the volatility of capital flows. Our results suggest there are commonalities in capital inflows, although aggregate or disaggregate capital flows respond differently to shocks. We find that the US long run real interest rate is an important determinant of global capital flows, and real commodity prices are relevant but to a lesser extent. We also find a role for human capital in explaining why some countries can successfully ride the wave of financial globalisation.Capital Flows; Emerging Markets; Developing Countries; Global Factors
Hofstadter butterflies of bilayer graphene
We calculate the electronic spectrum of bilayer graphene in perpendicular
magnetic fields nonperturbatively. To accommodate arbitrary displacements
between the two layers, we apply a periodic gauge based on singular flux
vortices of phase . The resulting Hofstadter-like butterfly plots show a
reduced symmetry, depending on the relative position of the two layers against
each other. The split of the zero-energy relativistic Landau level differs by
one order of magnitude between Bernal and non-Bernal stacking.Comment: updated to refereed and edited versio
Bias in judgement: Comparing individuals and groups
The relative susceptibility of individuals and groups to systematic judgmental biases is considered. An overview of the relevant empirical literature reveals no clear or general pattern. However, a theoretical analysis employing J. H. Davis's (1973) social decision scheme (SDS) model reveals that the relative magnitude of individual and group bias depends upon several factors, including group size, initial individual judgment, the magnitude of bias among individuals, the type of bias, and most of all, the group-judgment process. It is concluded that there can be no simple answer to the question, "Which are more biased, individuals or groups?," but the SDS model offers a framework for specifying some of the conditions under which individuals are both more and less biased than groups
Primary commodity prices: co-movements, common factors and fundamentals
The behavior of commodities is critical for developing and developed countries alike. This paper contributes to the empirical evidence on the co-movement and determinants of commodity prices. Using nonstationary panel methods, we document a statistically significant degree of co-movement due to a common factor. Within a Factor Augmented VAR approach, real interest rate and uncertainty, as postulated by a simple asset pricing model, are both found to be negatively related to this common factor. This evidence is robust to the inclusion of demand and supply shocks, which both positively impact on the co-movement of commodity prices.Commodity Prices, Panel Estimation, Factor Models
Cardiac safety of tiotropium in patients with cardiac events: a retrospective analysis of the UPLIFT® trial.
BackgroundTiotropium is an anticholinergic bronchodilator for symptom relief and reducing exacerbations with an established safety profile in patients with chronic obstructive pulmonary disease (COPD). Using data from the 4-year Understanding Potential Long-term Impacts on Function with Tiotropium (UPLIFT®) study, we re-evaluated the safety of tiotropium HandiHaler® in patients who experienced recent myocardial infarction (MI), heart failure or unstable rhythm disorder during the study.MethodsA post-hoc analysis of all-cause mortality and serious cardiac adverse events (cardiac SAEs), including cardiac deaths and death unknown, was conducted in patients who had experienced cardiac arrhythmia, MI or cardiac failure during UPLIFT® and who completed the study. Descriptive analyses were performed.ResultsMost patients experiencing cardiac events, for which they would have been excluded at baseline, remained in the trial. Kaplan-Meier analyses revealed a trend to later occurrence of cardiac SAEs with tiotropium HandiHaler® versus placebo. Patients who experienced a cardiac event and continued in UPLIFT® were not found to be at subsequently increased risk of all-cause mortality or cardiac SAEs with tiotropium treatment. Evaluation of deaths by major adverse cardiac events composite endpoints also showed that patients treated with tiotropium were not at increased risk of mortality or cardiac SAEs compared with placebo.ConclusionsRisk of cardiac events, mortality or SAEs was not increased by tiotropium in patients experiencing cardiac events for which they would have been excluded at study baseline. The findings support the cardiac safety of tiotropium HandiHaler® in patients with COPD
The Global Side of the Investments-Savings Puzzle
In this paper we re-examine the long standing and puzzling correlation between national savings and investment in industrial countries. We apply an econometric methodology that allows us to separate idiosyncratic correlation at the country level from correlation at the global level. In a major break with the existing literature, we find no evidence of a long run relationship in the idiosyncratic components of savings and investment. We also find that the global components in savings and investments commove, indicating that they react to shocks of a global nature.Savings, Investment, Feldstein-Horioka Puzzle, Panel Nonstationarity, Principal Components.
The Global Dimension to Fiscal Sustainability
This paper examines the issue of fiscal sustainability in emerging market countries and industrial countries. We highlight the importance of the time series properties of the primary surplus and debt, and find evidence of a positive long run relationship. Consequently we emphasise, that especially for emerging markets, it is important to recognise the implications of global capital market shocks for fiscal sustainability, a relationship which has hitherto been ignored in the empirical literature. Using a factor model we demonstrate that the relationship between deficit and debt is conditional upon a global factor and we suggest that this global factor is related to worldwide liquidity. We also demonstrate that this acts as a constraint on emerging market economies’ fiscal policy.Fiscal Policy; Sustainability.
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