12,634 research outputs found
Does Falling Smoking Lead to Rising Obesity?
The strong negative correlation over time between smoking rates and obesity have led some to suggest that reduced smoking is increasing weight gain in the U.S.. This conclusion is supported by the findings of Chou et al. (2004), who conclude that higher cigarette prices lead to increased body weight. We investigate this issue and find no evidence that reduced smoking leads to weight gain. Using the cigarette tax rather than the cigarette price and controlling for non-linear time effects, we find a negative effect of cigarette taxes on body weight, implying that reduced smoking leads to lower body weights. Yet our results, as well as Chou et al., imply implausibly large effects of smoking on body weight. Thus, we cannot confirm that falling smoking leads in a major way to rising obesity rates in the U.S
Creating New Ventures: A review and research agenda
Creating new ventures is one of the most central topics to entrepreneurship and is a critical step from which many theories of management, organizational behavior, and strategic management build. Therefore, this review and proposed research agenda is not only relevant to entrepreneurship scholars but also other management scholars who wish to challenge some of the implicit assumptions of their current streams of research and extend the boundaries of their current theories to earlier in the organization’s life. Given that the last systematic review of the topic was published 16 years ago, and that the topic has evolved rapidly over this time, an overview and research outlook are long overdue. From our review, we inductively generated ten sub-topics: (1) Lead founder, (2) Founding team, (3) Social relationships, (4) Cognitions, (5) Emergent organizing, (6) New venture strategy, (7) Organizational emergence, (8) New venture legitimacy, (9) Founder exit, and (10) Entrepreneurial environment. These sub-topics are then organized into three major stages of the entrepreneurial process—co-creating, organizing, and performing. Together, the framework provides a cohesive story of the past and a road map for future research on creating new ventures, focusing on the links connecting these sub-topics
-approximation of the integrated density of states for Schr\"odinger operators with finite local complexity
We study spectral properties of Schr\"odinger operators on \RR^d. The
electromagnetic potential is assumed to be determined locally by a colouring of
the lattice points in \ZZ^d, with the property that frequencies of finite
patterns are well defined. We prove that the integrated density of states
(spectral distribution function) is approximated by its finite volume
analogues, i.e.the normalised eigenvalue counting functions. The convergence
holds in the space where is any finite energy interval and is arbitrary.Comment: 15 pages; v2 has minor fixe
SU(m|n) supersymmetric Calogero-Sutherland model confined in harmonic potential
In this work, we study a continuous quantum system of a mixture of bosons and
fermions with the supersymmetry SU(m|n). The particles are confined in a
harmonic well and interact with each other through the 1/r2 interaction. The
ground state wavefunction is constructed explicitly for the most general
SU(m|n) case, with the ground state energy given explicitly. The full energy
spectrum of excitations in the SU(m|n) model is also equal spaced. In the
limiting case where there are no bosons in the system, our results reduce to
those obtained previously.Comment: 9 pages, preprint of ETH-Lausanne (August 1996
Ground States and Flux Configurations of the Two-dimensional Falicov-Kimball Model
The Falicov-Kimball model is a lattice model of itinerant spinless fermions
("electrons") interacting by an on-site potential with classical particles
("ions"). We continue the investigations of the crystalline ground states that
appear for various filling of electrons and ions, for large coupling. We
investigate the model for square as well as triangular lattices. New ground
states are found and the effects of a magnetic flux on the structure of the
phase diagram is studied. The flux phase problem where one has to find the
optimal flux configurations and the nuclei configurations is also solved in
some cases. Finaly we consider a model where the fermions are replaced by
hard-core bosons. This model also has crystalline ground states. Therefore
their existence does not require the Pauli principle, but only the on-site
hard-core constraint for the itinerant particles.Comment: 42 pages, uuencoded postscript file. Missing pages adde
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