On the first Dirichlet Laplacian eigenvalue of regular Polygons

The Faber-Krahn inequality in $\mathbb{R}^2$ states that among all open bounded sets of given area the disk minimizes the first Dirichlet Laplacian eigenvalue. There are numerical evidences that for all $N\ge 3$ the first Dirichlet Laplacian eigenvalue of the regular $N$-gon is greater than the one of the regular $(N+1)$-gon of same area. This natural property is also suggested by the fact that the shape of regular polygons becomes more and more "rounded" as $N$ increases and, among sets of given area, disk minimize the eigenvalue. Aiming to settle such a conjecture, in this work we investigate possible ways to estimate the difference between eigenvalues of regular $N$-gons and $(N+1)$-gons.Comment: This paper has been written for possible publication in a special volume dedicated to the conference "Third Italian-Japanese Workshop on Geometric Properties for Parabolic and Elliptic PDE's", organized in Tokyo in August 201

Fly or Cry: Is Airport Noise Costly?

Airport noise is costly. Airport location is typically associated with lower property prices. Airport expansion often sparks protests by local residents. In this paper, I provide new evidence on the costs of airport-related noise (and other disamenities of airports) for individuals. In contrast to previous work, I analyze voting results on restricting airport operations. Using data from a referendum on the closure of one of Berlin’s inner-city airports, Tempelhof, I find that voting behavior is not primarily explained by exposure to airport disamenities. Rather, strong opposition to closure in the vicinity of Tempelhof indicates that adaptive preferences may be important.noise, preferences, traffic, airports

Die Another Day: Duration in German Import Trade

International trade patterns at the product level are surprisingly dynamic. The majority of trade relationships exist for just a few, often only two to four, years. In this paper, I examine empirically the duration in German import trade at the 8-digit product level from 1995 to 2005. I find that survival probabilities are affected by product type, exporter characteristics and market structure. Specifically, I show that the duration of exporting a product to Germany is longer for differentiated products, for products with a low elasticity of substitution, for products obtained from a large exporter that is geographically close to the German market, and for products in markets with increasing import demand.Survival, product, relationship, pattern

Trade Mispricing and Illicit Flows

A potential vehicle to move capital unrecorded out of a country is the misinvoicing of international trade transactions. Exporters may understate the export revenue on their invoices and importers may overstate import expenditures, while their trading partners are instructed to deposit the balance for their benefit in a foreign account. Aiming to quantify the extent of trade mispricing, studies have analyzed asymmetries in matched partner trade statistics or examined price anomalies in transaction level price data. This paper critically reviews these empirical approaches and briefly describes an alternative methodology. Overall, the accuracy and reliability of estimates of illicit financial flows based on trade mispricing are questioned. In particular, it is argued that estimates of trade mispricing are critically dependent on assumptions on how to interpret observed asymmetries in trade statistics. For instance, various reasons for discrepancies in bilateral trade statistics are discussed, and incentives for faking trade invoices other than capital flight are highlighted. Also, aggregate trade data may mask considerable variation in trade discrepancies at the transaction level. Most notably, the importance of trade mispricing as a method for the unrecorded cross-border transfer of capital is generally unclear.

Die another day: duration in German import trade

International trade patterns at the product level are surprisingly dynamic. The majority of trade relationships exist for just a few, often only one to three, years. In this paper, I examine empirically the duration in German import trade at the 8-digit product level from 1995 to 2005. I find that survival probabilities are affected by exporter characteristics, product type and market structure. Specifically, I show that the duration of exporting a product to Germany is longer for products obtained from countries that are economically large and geographically close to Germany; for products with large trade value and a low elasticity of substitution; and for trade pairs that command a large share of the German import market and are characterized by two-way trade. --Survival,product,relationship,pattern

Currency union entries and trade

Recent research suggests that adopting a common currency increases bilateral trade. In this paper, I explore experiences of currency union entry in the post-war period and find no effect on trade. Previous results derived from a large panel data set (covering more than 200 countries from 1948 through 1997) appear to depend crucially on the assumption of symmetry between currency union exits and entries: While countries leaving a currency union experience significant declines in trade, currency union entry appears to have no measurable effect on trade. Also, in a detailed analysis of the enlargement of the CFA franc zone, I find no consistent results on changes in the pattern of trade. --accession,adoption,common currency,monetary integration

Zipf zipped

In this paper, I provide a quantitative review of the empirical literature on Zipf's law for cities; the meta-analysis combines 515 estimates from 29 studies. I find that the combined estimate of the Zipf coefficient is significantly larger than 1.0. This finding implies that cities are on average more evenly distributed than suggested by (a strict interpretation of) Zipf's law. I also identify several features that account for differences across the individual point estimates. --Zipf's law,size distribution of cities,rank size rule,meta-analysis

Does the G7/G8 promote trade?

The Group of Eight (G8) is an unofficial forum of the heads of state of the eight leading industrialized countries. In this paper, I examine the effect of the G8 (and its predecessor, the G7) on international trade. I use a gravity model of trade; the panel data set covers bilateral trade between 175 countries from 1948 through 1999. I find that membership in the G7/G8 is consistently associated with a strong positive effect on trade. --institution,organization,agreement,international,multilateral,summit

State Visits and International Trade

Politicians travel extensively abroad, for various reasons. One purpose of external visits is to improve bilateral economic relations. In this paper, I examine the effect of state visits on international trade. I use a large data set covering the travel activities of the heads of state of France, Germany and the United States between 1948 and 2003. My results indicate that state and official visits are indeed positively correlated with exports. A typical visit is associated with higher bilateral exports by about 8 to 10 percent, holding other things constant.head, president, government, politics, gravity

State visits and international trade

Politicians travel extensively abroad, for various reasons. One purpose of external visits is to improve bilateral economic relations. In this paper, I examine the effect of state visits on international trade. I use a large data set covering the travel activities of the heads of state of France, Germany and the United States between 1948 and 2003. My results indicate that state and official visits are indeed positively correlated with exports. A typical visit is associated with higher bilateral exports by about 8 to 10 per cent, holding other things constant. --head,president,government,politics,gravity