A TQFT of Intersection Numbers on Moduli Spaces of Admissible Covers

We construct a two-level weighted TQFT whose structure coefficents are equivariant intersection numbers on moduli spaces of admissible covers. Such a structure is parallel (and strictly related) to the local Gromov-Witten theory of curves of Bryan-Pandharipande. We compute explicitly the theory using techniques of localization on moduli spaces of admissible covers of a parametrized projective line. The Frobenius Algebras we obtain are one parameter deformations of the class algebra of the symmetric group S_d. In certain special cases we are able to produce explicit closed formulas for such deformations in terms of the representation theory of S_d

Hodge-type integrals on moduli spaces of admissible covers

We study Hodge Integrals on Moduli Spaces of Admissible Covers. Motivation for this work comes from Bryan and Pandharipande's recent work on the local GW theory of curves, where analogouos intersection numbers, computed on Moduli Spaces of Relative Stable Maps, are the structure coefficients for a Topological Quantum Field Theory. Admissible Covers provide an alternative compactification of the Moduli Space of Maps, that is smooth and doesn't contain boundary components of excessive dimension. A parallel, yet different, TQFT, can then be constructed. In this paper we compute, using localization, the relevant Hodge integrals for admissible covers of a pointed sphere of degree 2 and 3, and formulate a conjecture for general degree. In genus 0, we recover the well-known Aspinwall Morrison formula in GW theory.Comment: This is the version published by Geometry & Topology Monographs on 21 September 200

A survey of existing music programs and scheduling practices in junior high schools of large cities in the United States

Thesis (Ed.M.)--Boston University PLEASE NOTE: both the original and carbon copies of this thesis were of poor print quality. We have chosen to retain both in OpenBU, and recommend that if you feel one is inadequate, you try the other

Geographical patterns of unmet health care needs in Italy

In recent years, health care reforms and restrained budgets have risen concerns about accessibility to health services, even in countries with universal coverage health systems. Previous studies have explored the issue by using objective event-oriented measures such as those related to utilization of health care. Analyzing access through subjective process-oriented indicators allows to better disentangle the process of seeking care, to investigate self-perceived barriers to health services and to account for differences in individual health care preferences. In this paper, data from the 2006 Italian component of the European Survey on Income and Living Conditions (EU-SILC) are used to explore reasons and predictors of self-reported unmet needs for specialist and/or dental care among adult Italians aged 18 and over. Results reveal different patterns across socio-economic groups and geographical macro-areas. Evidence of income-related inequalities and violations of the horizontal equity principle are also found both at a national and regional level. Policies to address unmet health care needs should adopt a multidimensional approach and be tailored so as to consider such heterogeneities.Unmet health care needs; access to health care; inequality; inequity; Italy

A geometric perspective on the piecewise polynomiality of double Hurwitz numbers

We describe double Hurwitz numbers as intersection numbers on the moduli space of curves. Assuming polynomiality of the Double Ramification Cycle (which is known in genera 0 and 1), our formula explains the polynomiality in chambers of double Hurwitz numbers, and the wall crossing phenomenon in terms of a variation of correction terms to the {\psi} classes. We interpret this as suggestive evidence for polynomiality of the Double Ramification Cycle.Comment: 15 pages, 5 figure