179 research outputs found
The vicious cycle: fundraising and perceived visibility in US presidential primaries
Scholars of presidential primaries have long posited a dynamic positive feedback loop between fundraising and electoral success. Yet existing work on both directions of this feedback remains inconclusive and is often explicitly cross-sectional, ignoring the dynamic aspect of the hypothesis. Pairing high-frequency FEC data on contributions and expenditures with Iowa Electronic Markets data on perceived probability of victory, we examine the bidirectional feedback between contributions and viability. We find robust, significant positive feedback in both directions. This might suggest multiple equilibria: a candidate initially anointed as the front-runner able to sustain such status solely by the fundraising advantage conferred despite possessing no advantage in quality. However, simulations suggest the feedback loop cannot, by itself, sustain advantage. Given the observed durability of front-runners, it would thus seem there is either some other feedback at work and/or the process by which the initial front-runner is identified is informative of candidate quality
Discrete Scale Invariance and the "Second Black Monday"
Evidence is offered for log-periodic (in time) fluctuations in the S&P 500
stock index during the three years prior to the October 27, 1997 "correction".
These fluctuations were expected on the basis of a discretely scale invariant
rupture phenomenology of stock market crashes proposed earlier.Comment: LaTeX file, 4 pages, 2 figure
Equivalent Representations of Non-Exponential Discounting Models
I characterize the entire class of consumption rules for finite-horizon models in which consumption is proportional to lifetime wealth. Any such rule can be obtained from a preference model with CRRA period utility. In a steady state with constant interest rates, a proportional consumption rule can be derived from a model with time-consistent preferences or from a model with possibly time-inconsistent preferences in which a household continually reoptimizes future utility discounted relative to the present instant. These two preference models will only coincide for the special case when the discount function is exponential. More generally, there will be two distinct yet observationally equivalent preference models. Hyperbolic-like discounting may arise because that is a simpler way for the brain to process a standard exponential discount function after accounting for mortality risk
Gravitational Analogues of Non-linear Born Electrodynamics
Gravitational analogues of the nonlinear electrodynamics of Born and of Born
and Infeld are introduced and applied to the black hole problem. This work is
mainly devoted to the 2-dimensional case in which the relevant lagrangians are
nonpolynomial in the scalar curvature.Comment: 20 pages, 2 figures, included a detailed discussion of "non-trace"
field equation
More on A Statistical Analysis of Log-Periodic Precursors to Financial Crashes
We respond to Sornette and Johansen's criticisms of our findings regarding
log-periodic precursors to financial crashes. Included in this paper are
discussions of the Sornette-Johansen theoretical paradigm, traditional methods
of identifying log-periodic precursors, the behavior of the first differences
of a log-periodic price series, and the distribution of drawdowns for a
securities price.Comment: 12 LaTex pages, no figure
The Vicious Cycle: Fundraising and Perceived Viability in U.S. Presidential Primaries
Scholars of presidential primaries have long posited a dynamic positive feedback loop between fundraising and electoral success. Yet existing work on both directions of this feedback remains inconclusive and is often explicitly cross-sectional, ignoring the dynamic aspect of the hypothesis. Pairing high-frequency FEC data on contributions and expenditures with Iowa Electronic Markets data on perceived probability of victory, we examine the bidirectional feedback between contributions and viability. We find robust, significant positive feedback in both directions. This might suggest multiple equilibria: a candidate initially anointed as the front-runner able to sustain such status solely by the fundraising advantage conferred despite possessing no advantage in quality. However, simulations suggest the feedback loop cannot, by itself, sustain advantage. Given the observed durability of front-runners, it would thus seem there is either some other feedback at work and/or the process by which the initial front-runner is identified is informative of candidate quality
Born-Regulated Gravity in Four Dimensions
Previous work involving Born-regulated gravity theories in two dimensions is
extended to four dimensions. The action we consider has two dimensionful
parameters. Black hole solutions are studied for typical values of these
parameters. For masses above a critical value determined in terms of these
parameters, the event horizon persists. For masses below this critical value,
the event horizon disappears, leaving a ``bare mass'', though of course no
singularity.Comment: LaTeX, 15 pages, 2 figure
The Grizzly, September 12, 2013
Reimert Arrest • USGA Leadership Retreat • Construction in Thomas and Pfahler • Ursinus Site Undergoes Update • 14th Annual Fringe Festival • New Pitch Program Rewards Creativity • Policy Changes a Result of Student Demand • Opinion: Chemical Attacks Need International Response; We Should Stay Out of Syria • UC\u27s Open Laptops • Volleyball Counting on Newcomers This Season • Athletic Training Room Source of Aid and Knowledge • Men\u27s Soccer Looking to Improve • More Shots a Priority for Bearshttps://digitalcommons.ursinus.edu/grizzlynews/1885/thumbnail.jp
Visualization and Identification of IL-7 Producing Cells in Reporter Mice
Interleukin-7 (IL-7) is required for lymphocyte development and homeostasis although the actual sites of IL-7 production have never been clearly identified. We produced a bacterial artificial chromosome (BAC) transgenic mouse expressing ECFP in the Il7 locus. The construct lacked a signal peptide and ECFP (enhanced cyan fluorescent protein ) accumulated inside IL-7-producing stromal cells in thoracic thymus, cervical thymus and bone marrow. In thymus, an extensive reticular network of IL-7-containing processes extended from cortical and medullary epithelial cells, closely contacting thymocytes. Central memory CD8 T cells, which require IL-7 and home to bone marrow, physically associated with IL-7-producing cells as we demonstrate by intravital imaging
Visualization and Identification of IL-7 Producing Cells in Reporter Mice
Interleukin-7 (IL-7) is required for lymphocyte development and homeostasis although the actual sites of IL-7 production have never been clearly identified. We produced a bacterial artificial chromosome (BAC) transgenic mouse expressing ECFP in the Il7 locus. The construct lacked a signal peptide and ECFP (enhanced cyan fluorescent protein ) accumulated inside IL-7-producing stromal cells in thoracic thymus, cervical thymus and bone marrow. In thymus, an extensive reticular network of IL-7-containing processes extended from cortical and medullary epithelial cells, closely contacting thymocytes. Central memory CD8 T cells, which require IL-7 and home to bone marrow, physically associated with IL-7-producing cells as we demonstrate by intravital imaging
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