2,448 research outputs found
Predictive Modeling of the Non-Profit Sector in the US
The Non-Profit Sector contributes almost $1 trillion to the US economy, representing 5.4% of GDP, and generating over 12 million jobs in 2017. Yi (2010) suggests that a better understanding of the factors that affect fundraising should be of great interest to policy makers, and fundraisers. However, the workings of the sector are subject of much debate. Matsunaga, Yamauchi and Okuyama (2010) relate its size to the Theory of Government Failure. Sokolowski (2013) proposes that government funding does have a positive effect on revenues. Curry, Rodin and Carlson (2012) suggested they swing with GDP, but, Berman, Brooks and Murphy (2006) contend that macroeconomic variables do not affect short-run dynamics. List (2011) found that non-profit revenues react more to economic upswings than downturns. And the National Philanthropic Trust (2016) relates ups and downs to certain events and public awareness. Wallace (2016) points to the fact that predictive modeling has focused big-donor analytics, aimed at the identification of potential donors. We set out instead to define a working model. After locating complete time series for an emblematic segment, the environmental cause, Factor Analysis allowed us to pinpoint independent variables. We found that Non-Profit Revenues (NPR) depend largely on Public Awareness, as measured by TV coverage, and Disposable Personal Income (DPI), specifically: NPR = -4401.542 + 528.327(DPI) +23.121(TVCoverage) +
QCD condensates and holographic Wilson loops for asymptotically AdS spaces
The minimization of the Nambu-Goto action for a surface whose contour defines
a circular Wilson loop of radius a placed at a finite value of the coordinate
orthogonal to the boundary is considered. This is done for asymptotically AdS
spaces. The condensates of even dimension through are calculated in
terms of the coefficient of in the expansion of the on-shell subtracted
Nambu-Goto action for small
The subtraction employed is such that it presents no conflict with conformal
invariance in the AdS case and need not introduce an additional infrared scale
for the case of confining geometries. It is shown that the UV value of the
condensates is universal in the sense that they only depends on the first
coefficients of the difference with the AdS case.Comment: 11 pages, 1 figur
Normal Coordinates and Primitive Elements in the Hopf Algebra of Renormalization
We introduce normal coordinates on the infinite dimensional group
introduced by Connes and Kreimer in their analysis of the Hopf algebra of
rooted trees. We study the primitive elements of the algebra and show that they
are generated by a simple application of the inverse Poincar\'e lemma, given a
closed left invariant 1-form on . For the special case of the ladder
primitives, we find a second description that relates them to the Hopf algebra
of functionals on power series with the usual product. Either approach shows
that the ladder primitives are given by the Schur polynomials. The relevance of
the lower central series of the dual Lie algebra in the process of
renormalization is also discussed, leading to a natural concept of
-primitiveness, which is shown to be equivalent to the one already in the
literature.Comment: Latex, 24 pages. Submitted to Commun. Math. Phy
ON GAUGINO CONDENSATION WITH FIELD-DEPENDENT GAUGE COUPLINGS
We study in detail gaugino condensation in globally and locally
supersymmetric Yang-Mills theories. We focus on models for which gauge-neutral
matter couples to the gauge bosons only through nonminimal gauge kinetic terms,
for the cases of one and several condensing gauge groups. Using only symmetry
arguments, the low-energy expansion, and general properties of supersymmetry,
we compute the low energy Wilson action, as well as the (2PI) effective action
for the composite {\it classical} superfield U\equiv\langle \Tr\WW \rangle,
with the supersymmetric gauge field strength. The 2PI effective
action provides a firmer foundation for the approach of Veneziano and
Yankielowicz, who treated the composite superfield, , as a quantum degree of
freedom. We show how to rederive the Wilson action by minimizing the 2PI action
with respect to . We determine, in both formulations and for global and
local supersymmetry, the effective superpotential, , the non-perturbative
contributions to the low-energy K\"ahler potential , and the leading higher
supercovariant derivative terms in an expansion in inverse powers of the
condensation scale. As an application of our results we include the string
moduli dependence of the super- and K\"ahler potentials for simple orbifold
models.Comment: 54 pages, plain te
Comment on "Geometrothermodynamics of a Charged Black Hole of String Theory"
We comment on the conclusions found by Larra\~naga and Mojica regarding the
consistency of the Geoemtrothermodynamics programme to describe the critical
behaviour of a Gibbons-Maeda-Garfinkle-Horowitz-Strominger charged black hole.
We argue that making the appropriate choice of metric for the thermodynamic
phase space and, most importantly, considering the homogeneity of the
thermodynamic potential we obtain consistent results for such a black hole.Comment: Comment on arXiv:1012.207
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