546,310 research outputs found
Local Employment, Poverty, and Property Value Effects of Geographically-Targeted Tax Incentives: An Instrumental Variables Approach
The federal Empowerment Zone (EZ) program is a set of tax incentives targeted to areas of select cities. I estimate the effect of the EZ program on employment, poverty, and property values by comparing areas that received an EZ to areas that applied (and qualified), but were rejected. Because of endogeneity concerns, I use political representation to instrument for EZ designation. OLS results show a positive and statistically significant effect of the program on employment and poverty. IV estimates suggest the program had no effect on employment and poverty, and instead had a large statistically significant effect on property values
Exclusion zone phenomena in water -- a critical review of experimental findings and theories
The existence of the exclusion zone (EZ), a layer of water in which plastic
microspheres are repelled from hydrophilic surfaces, has now been independently
demonstrated by several groups. A better understanding of the mechanisms which
generate EZs would help with understanding the possible importance of EZs in
biology and in engineering applications such as filtration and microfluidics.
Here we review the experimental evidence for EZ phenomena in water and the
major theories that have been proposed. We review experimental results from
birefringence, neutron radiography, nuclear magnetic resonance, and other
studies. Pollack and others have theorized that water in the EZ exists has a
different structure than bulk water, and that this accounts for the EZ. We
present several alternative explanations for EZs and argue that Schurr's theory
based on diffusiophoresis presents a compelling alternative explanation for the
core EZ phenomenon. Among other things, Schurr's theory makes predictions about
the growth of the EZ with time which have been confirmed by Florea et al. and
others. We also touch on several possible confounding factors that make
experimentation on EZs difficult, such as charged surface groups, dissolved
solutes, and adsorbed nanobubbles.Comment: 14 pg
EZ-AG: Structure-free data aggregation in MANETs using push-assisted self-repelling random walks
This paper describes EZ-AG, a structure-free protocol for duplicate
insensitive data aggregation in MANETs. The key idea in EZ-AG is to introduce a
token that performs a self-repelling random walk in the network and aggregates
information from nodes when they are visited for the first time. A
self-repelling random walk of a token on a graph is one in which at each step,
the token moves to a neighbor that has been visited least often. While
self-repelling random walks visit all nodes in the network much faster than
plain random walks, they tend to slow down when most of the nodes are already
visited. In this paper, we show that a single step push phase at each node can
significantly speed up the aggregation and eliminate this slow down. By doing
so, EZ-AG achieves aggregation in only O(N) time and messages. In terms of
overhead, EZ-AG outperforms existing structure-free data aggregation by a
factor of at least log(N) and achieves the lower bound for aggregation message
overhead. We demonstrate the scalability and robustness of EZ-AG using ns-3
simulations in networks ranging from 100 to 4000 nodes under different mobility
models and node speeds. We also describe a hierarchical extension for EZ-AG
that can produce multi-resolution aggregates at each node using only O(NlogN)
messages, which is a poly-logarithmic factor improvement over existing
techniques
EZ: A Tool for Automatic Redshift Measurement
We present EZ (Easy redshift), a tool we have developed within the VVDS
project to help in redshift measurement from otpical spectra. EZ has been
designed with large spectroscopic surveys in mind, and in its development
particular care has been given to the reliability of the results obtained in an
automatic and unsupervised mode. Nevertheless, the possibility of running it
interactively has been preserved, and a graphical user interface for results
inspection has been designed. EZ has been successfully used within the VVDS
project, as well as the zCosmos one. In this paper we describe its architecture
and the algorithms used, and evaluate its performances both on simulated and
real data. EZ is an open source program, freely downloadable from
http://cosmos.iasf-milano.inaf.it/pandora.Comment: accepted for publication in Publications of the Astronomical Society
of the Pacifi
Globalization, entrepreneurship and the region
The present document analyzes the linkages between globalization, entrepreneurship and the role of regions. After dealing with the meaning of globalization, the regional dimension of the response to globalization is described where downsizing, knowledge spillovers and agglomeration are the essential phenomena. Next, it is shown how these developments have led to the emergence of new entrepreneurial activities. Subsequently, more details are given on the effects of the information and communication (ICT) revolution on the organization of industry in a globalized economy. Finally, it is concluded that policies promoting both knowledge investments as well as entrepreneurship have become prominent for many regions in the most developed countries. ïżœ
Self-employment across 15 European countries: the role of dissatisfaction
This paper deals with differences in the rate of self-employment (business ownership) in 15 European countries for the period 1978-2000, focusing on the influence of dissatisfaction and using the framework of occupational choice. Using two different measures of dissatisfaction, in addition to the level of economic development, the unemployment rate and income differentials, we find that dissatisfaction at the level of societies is the most significant factor for explaining differences in self-employment levels. Dissatisfaction with life and with the way democracy works are both found to be positively related to self-employment. It is concluded that these are proxies for job dissatisfaction and at the same time represent other negative 'displacements' known to promote self-employment.
Export Orientation among New Ventures and Economic Growth
While it is generally acknowledged that entrepreneurship as well as export activity may both be important strategies for achieving national economic growth, it has remained unclear how export activity among new ventures is related to economic growth. This paper investigates whether the presence of export-oriented entrepreneurs is a more important determinant of economic growth than entrepreneurial activity in general. We focus on the national or macro-level and use data from the Global Entrepreneurship Monitor for a sample of 36 countries. An important advantage of using the macrolevel is that indirect effects of exporting entrepreneurs that reach further than the performance of these firms themselves (e.g. spillovers) are captured in the analysis. To our knowledge, no attempt has been made thus far to link international activity of early-stage ventures to macro-economic outcomes. Our results suggest that export-oriented entrepreneurship is indeed more important for achieving high economic growth rates than entrepreneurial activity in general. This suggests that international activity by small and new firms strongly contributes to higher levels of competition and, consequently, to the emergence of highly dynamic economies and higher levels of economic growth.
Motivation based policies for an entrepreneurial EU economy
This paper investigates the impact of various entrepreneurial motives and institutional conditions on entrepreneurial aspirations in terms of innovativeness, job growth expectations and export orientation. We estimate a two-equation model explaining entrepreneurial motivations and entrepreneurial aspirations, while taking into account the interrelationship between both groups of variables. We use data from the Global Entrepreneurship Monitor (GEM) and find that entrepreneurial aspirations are different for various types of entrepreneurial motives. For example, we find that the increase wealth motive as a prime driver for becoming selfemployed is positively related to innovation and growth ambitions, whereas we find no evidence of a relation between the independence motive and entrepreneurial aspirations. On the basis of our findings policy directions are presented for an entrepreneurial EU economy. An updated version of this paper is numbered H200710.
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