34,407 research outputs found
Towards an Abstract Domain for Resource Analysis of Logic Programs Using Sized Types
We present a novel general resource analysis for logic programs based on
sized types.Sized types are representations that incorporate structural (shape)
information and allow expressing both lower and upper bounds on the size of a
set of terms and their subterms at any position and depth. They also allow
relating the sizes of terms and subterms occurring at different argument
positions in logic predicates. Using these sized types, the resource analysis
can infer both lower and upper bounds on the resources used by all the
procedures in a program as functions on input term (and subterm) sizes,
overcoming limitations of existing analyses and enhancing their precision. Our
new resource analysis has been developed within the abstract interpretation
framework, as an extension of the sized types abstract domain, and has been
integrated into the Ciao preprocessor, CiaoPP. The abstract domain operations
are integrated with the setting up and solving of recurrence equations for
both, inferring size and resource usage functions. We show that the analysis is
an improvement over the previous resource analysis present in CiaoPP and
compares well in power to state of the art systems.Comment: Part of WLPE 2013 proceedings (arXiv:1308.2055
When innovation requirements empower individual innovation : the role of job complexity
The purpose of this paper is to contribute to the field's understanding of how to raise individual innovation. Specifically, the authors aim to contribute to an understanding of the interplay of job characteristics and intrinsic motivation for individual innovation
Social choice theory, game theory, and positive political theory
We consider the relationships between the collective preference and non-cooperative game theory approaches to positive political theory. In particular, we show that an apparently decisive difference between the two approachesthat in sufficiently complex environments (e.g. high-dimensional choice spaces) direct preference aggregation models are incapable of generating any prediction at all, whereas non-cooperative game-theoretic models almost always generate predictionis indeed only an apparent difference. More generally, we argue that when modeling collective decisions there is a fundamental tension between insuring existence of well-defined predictions, a criterion of minimal democracy, and general applicability to complex environments; while any two of the three are compatible under either approach, neither collective preference nor non-cooperative game theory can support models that simultaneously satisfy all three desiderata
Aggregation and Seasonal Adjustment: Empirical Results for EMU Quarterly National Accounts
This paper investigates the differences between directly and indirectly seasonally adjusted aggregates. This difference is derived analytically for linear seasonal adjustment methods. GDP data for five European countries and three classes of seasonal adjustment methods are used to show empirically the differences between both approaches. For this purpose cointegration methods and cross-spectral analysis are applied. The analysis shows that there are no differences in the long-run components of directly and indirectly adjusted aggregates, whereas differences in the short-run components depend strongly on the seasonal adjustment methods applied in the indirect and direct approaches.
Spatial aggregation of local likelihood estimates with applications to classification
This paper presents a new method for spatially adaptive local (constant)
likelihood estimation which applies to a broad class of nonparametric models,
including the Gaussian, Poisson and binary response models. The main idea of
the method is, given a sequence of local likelihood estimates (``weak''
estimates), to construct a new aggregated estimate whose pointwise risk is of
order of the smallest risk among all ``weak'' estimates. We also propose a new
approach toward selecting the parameters of the procedure by providing the
prescribed behavior of the resulting estimate in the simple parametric
situation. We establish a number of important theoretical results concerning
the optimality of the aggregated estimate. In particular, our ``oracle'' result
claims that its risk is, up to some logarithmic multiplier, equal to the
smallest risk for the given family of estimates. The performance of the
procedure is illustrated by application to the classification problem. A
numerical study demonstrates its reasonable performance in simulated and
real-life examples.Comment: Published in at http://dx.doi.org/10.1214/009053607000000271 the
Annals of Statistics (http://www.imstat.org/aos/) by the Institute of
Mathematical Statistics (http://www.imstat.org
PLS dimension reduction for classification of microarray data
PLS dimension reduction is known to give good prediction accuracy in the context of classification with high-dimensional microarray data. In this paper, PLS is compared with some of the best state-of-the-art classification methods. In addition, a simple procedure to choose the number of components is suggested. The connection between PLS dimension reduction and gene selection is examined and a property of the first PLS component for binary classification is proven. PLS can also be used as a visualization tool for high-dimensional data in the classification framework. The whole study is based on 9 real microarray cancer data sets
Where Is the Power? Transnational Networks, Authority and the Dispute over the Xayaburi Dam on the Lower Mekong Mainstream
Accounts of hydro-hegemony and counter hydro-hegemony provide state-based conceptions of power in international river basins. However, authority should be seen as transnationalized as small states develop coping strategies to augment their authority over decision-making processes. The article engages Rosenau’s spheres of authority concept to argue that hydro-hegemony is exercised by actors embedded in spheres of authority that reshape actor configurations as they emerge. These spheres consist of complex networks challenging customary notions of the local-global dichotomy and hydro-hegemony. Hydro-hegemony is therefore not fixed. The article examines these processes by analysing the dispute over the Xayaburi Dam in the Mekong Basin
Change of Scaling and Appearance of Scale-Free Size Distribution in Aggregation Kinetics by Additive Rules
The idealized general model of aggregate growth is considered on the basis of
the simple additive rules that correspond to one-step aggregation process. The
two idealized cases were analytically investigated and simulated by Monte Carlo
method in the Desktop Grid distributed computing environment to analyze
"pile-up" and "wall" cluster distributions in different aggregation scenarios.
Several aspects of aggregation kinetics (change of scaling, change of size
distribution type, and appearance of scale-free size distribution) driven by
"zero cluster size" boundary condition were determined by analysis of evolving
cumulative distribution functions. The "pile-up" case with a \textit{minimum}
active surface (singularity) could imitate piling up aggregations of
dislocations, and the case with a \textit{maximum} active surface could imitate
arrangements of dislocations in walls. The change of scaling law (for pile-ups
and walls) and availability of scale-free distributions (for walls) were
analytically shown and confirmed by scaling, fitting, moment, and bootstrapping
analyses of simulated probability density and cumulative distribution
functions. The initial "singular" \textit{symmetric} distribution of pile-ups
evolves by the "infinite" diffusive scaling law and later it is replaced by the
other "semi-infinite" diffusive scaling law with \textit{asymmetric}
distribution of pile-ups. In contrast, the initial "singular"
\textit{symmetric} distributions of walls initially evolve by the diffusive
scaling law and later it is replaced by the other ballistic (linear) scaling
law with \textit{scale-free} exponential distributions without distinctive
peaks. The conclusion was made as to possible applications of such approach for
scaling, fitting, moment, and bootstrapping analyses of distributions in
simulated and experimental data.Comment: 37 pages, 16 figures, 1 table; accepted preprint version after
comments of reviewers, Physica A: Statistical Mechanics and its Applications
(2014
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