57,781 research outputs found
Dynamical Anomalous Subvarieties: Structure and Bounded Height Theorems
According to Medvedev and Scanlon, a polynomial
of degree is called disintegrated if it is not linearly conjugate to
or (where is the Chebyshev polynomial of degree
). Let , let be
disintegrated polynomials of degrees at least 2, and let
be the corresponding coordinate-wise
self-map of . Let be an irreducible subvariety of
of dimension defined over . We define
the \emph{-anomalous} locus of which is related to the
\emph{-periodic} subvarieties of . We prove that
the -anomalous locus of is Zariski closed; this is a dynamical
analogue of a theorem of Bombieri, Masser, and Zannier \cite{BMZ07}. We also
prove that the points in the intersection of with the union of all
irreducible -periodic subvarieties of of
codimension have bounded height outside the -anomalous locus of
; this is a dynamical analogue of Habegger's theorem \cite{Habegger09} which
was previously conjectured in \cite{BMZ07}. The slightly more general self-maps
where each is a
disintegrated rational map are also treated at the end of the paper.Comment: Minor mistakes corrected, slight reorganizatio
Static and dynamic semantics of NoSQL languages
We present a calculus for processing semistructured data that spans
differences of application area among several novel query languages, broadly
categorized as "NoSQL". This calculus lets users define their own operators,
capturing a wider range of data processing capabilities, whilst providing a
typing precision so far typical only of primitive hard-coded operators. The
type inference algorithm is based on semantic type checking, resulting in type
information that is both precise, and flexible enough to handle structured and
semistructured data. We illustrate the use of this calculus by encoding a large
fragment of Jaql, including operations and iterators over JSON, embedded SQL
expressions, and co-grouping, and show how the encoding directly yields a
typing discipline for Jaql as it is, namely without the addition of any type
definition or type annotation in the code
Non-gaussian Noise in Quantum Spin Glasses and Interacting Two-level Systems
We study a general model for non-gaussian noise based on an infinite
range quantum Ising spin system in the paramagnetic state, or equivalently,
interacting two-level classical fluctuators. We identify a dilatation
interaction term in the dynamics which survives the thermodynamic limit and
circumvents the central limit theorem to produce non-gaussian noise even when
the equilibrium distribution is that of {\em non-interacting} spins. The
resulting second spectrum (`noise of the noise') itself has a universal
form which we analyze within a dynamical mean field approximation.Comment: 4 pages, 3 figure
An Econometric Approach To Estimating Support Prices And Measures Of Productivity Change In Public Hospitals
In industry sectors where market prices are unavailable it is common to represent multiple-input multiple-output production technologies using distance functions. Econometric estimation of such functions is complicated by the fact that more than one variable in the function may be endogenous. In such cases, maximum likelihood estimation can lead to biased and inconsistent estimates of the model parameters and associated measures of firm performance. We solve the problem by using linear programming to construct a quantity index. The distance function is then written in the form of a conventional stochastic frontier model where the explanatory variables are unambiguously exogenous. We use this approach to estimate productivity indexes and support (or shadow) prices for a sample of Australian public hospitals. We decompose the productivity index into several measures of environmental change and efficiency change. We find that the productivity effects of improvements in input-oriented technical efficiency have been largely offset by the effects of deteriorations in the production environment over time.
Vietnam Inbound M&A Activity: the Role of Government Policy and Regulatory Environment
With a robust recent history of reform and opening, joining of the World Trade Organization, and negotiating a myriad of regional and global trade agreements, Vietnam has emerged as a promising destination for foreign direct investment(FDI) and cross-border mergers and acquisitions (M&A). In this paper, we providean overview of Vietnam’s inbound mergers and acquisitions and review the twomain driving forces of inbound M&A, which are the legal framework reformprocess and the equitization of State-owned enterprises. We close by providingdirections for future research in the area of cross-border M&As
Export intensity of foreign subsidiaries of multinational enterprises: the role of trade finance availability
We examine the relationship between the role of trade finance availability and the export intensity of foreign subsidiaries of multinational enterprises (MNEs). In developing our hypotheses, we draw upon insights derived from “new” internalisation theory (international business literature) and international trade finance (international economics literature). We empirically test these hypotheses using survey data compiled from subsidiary managers in six ASEAN countries, supplemented with host-country level data. We conceptualise, empirically test, and establish that the subsidiary-level capability in combining and utilising internal and external debts is an important subsidiary-specific advantage to support export intensity. We find that subsidiaries employ intra-firm loans from MNE internal capital markets and, to some extent, bank loans from external financial institutions to boost their export intensity. Subsidiaries may have concerns about foreign exchange risks, but the use of appropriate foreign exchange risk management is positively associated with export intensity. We discuss the implications of our findings for theory and practice
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