Results 41-60 of 8861.
Bookmark and Share    
Full Text
Peer Reviewed
See detailInvariance in a class of operations related to weighted quasi-geometric means
Devillet, Jimmy UL; Matkowski, Janusz

in Fuzzy Sets and Systems (in press)

Let $I\subset (0,\infty )$ be an interval that is closed with respect to the multiplication. The operations $C_{f,g}\colon I^{2}\rightarrow I$ of the form \begin{equation*} C_{f,g}\left( x,y\right) =\left ... [more ▼]

Let $I\subset (0,\infty )$ be an interval that is closed with respect to the multiplication. The operations $C_{f,g}\colon I^{2}\rightarrow I$ of the form \begin{equation*} C_{f,g}\left( x,y\right) =\left( f\circ g\right) ^{-1}\left( f\left( x\right) \cdot g\left( y\right) \right) \text{,} \end{equation*} where $f,g$ are bijections of $I$ are considered. Their connections with generalized weighted quasi-geometric means is presented. It is shown that invariance\ question within the class of this operations leads to means of iterative type and to a problem on a composite functional equation. An application of the invariance identity to determine effectively the limit of the sequence of iterates of some generalized quasi-geometric mean-type mapping, and the form of all continuous functions which are invariant with respect to this mapping are given. The equality of two considered operations is also discussed. [less ▲]

Detailed reference viewed: 57 (4 UL)
Full Text
See detailThe mod 2 cohomology rings of congruence subgroups in the Bianchi groups
Berkove, Ethan; Lakeland, Grant; Rahm, Alexander UL

E-print/Working paper (in press)

We provide new tools for the calculation of the torsion in the cohomology of congruence subgroups in the Bianchi groups : An algorithm for finding particularly useful fundamental domains, and an analysis ... [more ▼]

We provide new tools for the calculation of the torsion in the cohomology of congruence subgroups in the Bianchi groups : An algorithm for finding particularly useful fundamental domains, and an analysis of the equivariant spectral sequence combined with torsion subcomplex reduction. [less ▲]

Detailed reference viewed: 211 (4 UL)
Full Text
Peer Reviewed
See detailCorruption and tax compliance: evidence from small retailers in Bamako, Mali
Bertinelli, Luisito UL; Bourgain, Arnaud UL; Leon, Florian UL

in Applied Economics Letters (in press)

We investigate the impact of corruption on tax compliance using a sample of 700 small business in Bamako, Mali. The main contribution of this paper is to focus on micro-enterprises (including semi-formal ... [more ▼]

We investigate the impact of corruption on tax compliance using a sample of 700 small business in Bamako, Mali. The main contribution of this paper is to focus on micro-enterprises (including semi-formal and informal ones), while existing works concentrate on large and formal firms. Our results show that (i) even very small firms pay taxes (two-thirds of firms pay taxes in our sample); and, (ii) paying bribes reduces significantly tax compliance. This latter finding is robust (i) to the addition of a set of control variables accounting for other determinants, (ii) to treatment for endogeneity, and (iii) the use of a different proxy for tax compliance. [less ▲]

Detailed reference viewed: 120 (1 UL)
Full Text
Peer Reviewed
See detailDie Psychotechnik im Dienste der Berufsberatung - eine Erinnerung an die Verdienste von Nicolas Braunshausen
Steffgen, Georges UL; Ewen, Norbert UL

in Psychologische Rundschau: Ueberblick Uber die Fortschritte der Psychologie in Deutschland, Oesterreich, und der Schweiz (in press)

Detailed reference viewed: 39 (2 UL)
Full Text
Peer Reviewed
See detailA Bayesian framework to identify random parameter fields based on the copula theorem and Gaussian fields: Application to polycrystalline materials
Rappel, Hussein UL; Wu, Ling; Noels, Ludovic et al

in Journal of Applied Mechanics (in press)

For many models of solids, we frequently assume that the material parameters do not vary in space, nor that they vary from one product realization to another. If the length scale of the application ... [more ▼]

For many models of solids, we frequently assume that the material parameters do not vary in space, nor that they vary from one product realization to another. If the length scale of the application approaches the length scale of the micro-structure however, spatially fluctuating parameter fi elds (which vary from one realization of the fi eld to another) can be incorporated to make the model capture the stochasticity of the underlying micro-structure. Randomly fluctuating parameter fields are often described as Gaussian fields. Gaussian fi elds however assume that the probability density function of a material parameter at a given location is a univariate Gaussian distribution. This entails for instance that negative parameter values can be realized, whereas most material parameters have physical bounds (e.g. the Young's modulus cannot be negative). In this contribution, randomly fluctuating parameter fi elds are therefore described using the copula theorem and Gaussian fi elds, which allow di fferent types of univariate marginal distributions to be incorporated, but with the same correlation structure as Gaussian fields. It is convenient to keep the Gaussian correlation structure, as it allows us to draw samples from Gaussian fi elds and transform them into the new random fields. The bene fit of this approach is that any type of univariate marginal distribution can be incorporated. If the selected univariate marginal distribution has bounds, unphysical material parameter values will never be realized. We then use Bayesian inference to identify the distribution parameters (which govern the random fi eld). Bayesian inference regards the parameters that are to be identi fied as random variables and requires a user-defi ned prior distribution of the parameters to which the observations are inferred. For the homogenized Young's modulus of a columnar polycrystalline material of interest in this study, the results show that with a relatively wide prior (i.e. a prior distribution without strong assumptions), a single specimen is su ciffient to accurately recover the distribution parameter values. [less ▲]

Detailed reference viewed: 108 (7 UL)
Full Text
Peer Reviewed
See detailHigh-performance modeling of concrete ageing
Habera, Michal UL; Zilian, Andreas UL

in Proceedings in Applied Mathematics and Mechanics (in press)

Long-term behaviour of concrete structural elements is very important for evaluation of its health and serviceability range. The phenomena that must be considered are complex and lead to coupled ... [more ▼]

Long-term behaviour of concrete structural elements is very important for evaluation of its health and serviceability range. The phenomena that must be considered are complex and lead to coupled multiphysics formulations. Such formulations are difficult not only from physical perspective, but also from computational perspective. In this contribution attention to computational efficiency and effective implementation is payed. Presented model for concrete ageing is based on microprestress-solidification (MPS) theory of Bazant [1], Kunzel’s model for heat and moisture transport [2] and Mazars model for damage [3]. Ageing linear viscoelastic response, which is immanent to MPS theory and concrete creep, leads to ordinary differetial equation for internal variables solved for every quadrature/nodal point. Numerical structure of the finite element discretisation is examined. Few simplifications on physical model lead to a very efficient linear algebra problem for which standard preconditioned Krylov solvers are reviewed. In parallel, weak and strong scaling tests are performed. All results are produced within open-source finite element framework FEniCS [4]. These models are usually a basis for more involved thermo-hygro-chemo-mechanical (THCM) models with migrating chemical species. It is anticipated, that presented results will help practitioners or other structural engineerers with the choice of suitable and efficient methods for long-term concrete modeling. [less ▲]

Detailed reference viewed: 158 (19 UL)
Full Text
Peer Reviewed
See detailLa Charte dans l'action extérieure de l'Union européenne
Neframi, Eleftheria UL

in Iliopoulou Penot, Anastasia; Xenou, Lamprini (Eds.) La Charte des droits fondamentaux de l'UE (in press)

Detailed reference viewed: 63 (2 UL)
Full Text
Peer Reviewed
See detailChildhood Emotional Abuse and Cyberbullying Perpetration: The Role of Dark Personality Traits
Kircaburun, Kagan; Jonason, Peter; Griffiths, Mark D. et al

in Journal of Interpersonal Violence (in press), 0(0), 0886260519889930

Dark personality traits (i.e., Machiavellianism, psychopathy, narcissism, spitefulness, and sadism) are associated with adverse childhood experiences and deviant online behaviors. However, their mediating ... [more ▼]

Dark personality traits (i.e., Machiavellianism, psychopathy, narcissism, spitefulness, and sadism) are associated with adverse childhood experiences and deviant online behaviors. However, their mediating role between childhood emotional abuse and cyberbullying has never previously been investigated. We examined direct and indirect associations of childhood emotional abuse and cyberbullying via dark personality traits among 772 participants. Men were better characterized by dark personality traits and were more likely to engage in cyberbullying than women, and there were no sex differences in childhood emotional abuse. Collectively, dark traits fully mediated the relationship between childhood emotional abuse and cyberbullying in men, with partial mediation in the total sample and women. More specifically, Machiavellianism and spitefulness were mediators in both samples, sadism was a mediator in men and the total sample, and psychopathy was a mediator in the total sample and women. The dark personality traits can account for the association between childhood emotional abuse and cyberbullying, especially among men. [less ▲]

Detailed reference viewed: 139 (1 UL)
Full Text
Peer Reviewed
See detailThe Origins and Contemporary Development of Work-based Higher Education in Germany: Lessons for Anglophone Countries?
Graf, Lukas; Powell, Justin J W UL

in Wheelehan, Leesa; Bathmaker, Ann-Marie; Orr, Kevin (Eds.) et al Higher-level Vocational Education: The Route to High Skills and Productivity as well as Greater Equity? An International Comparative Analysis (in press)

Today, higher education is typically seen as offering the most assured pathways to secure careers and low unemployment rates. Yet, increasingly some groups, not least higher education graduates and their ... [more ▼]

Today, higher education is typically seen as offering the most assured pathways to secure careers and low unemployment rates. Yet, increasingly some groups, not least higher education graduates and their families paying ever-higher tuition fees, question the taken-for-granted contributions higher education makes to individuals and society as a whole. Despite decades of mass higher education expansion, even societies with strong systems continue to struggle to achieve their goal of universalizing participation and equalizing access. While in part this is due to limited public or corporate funding for (affordable) study opportunities, differentiated systems, such as in the US, also lack policy coordination and effective governance, providing a surfeit of options. While participation rates have climbed worldwide, higher education systems continue to produce winners (“insiders”) and losers (“outsiders”), even as the “schooled society” shifts the occupational structure upward. Market-oriented higher education systems face increasing privatization, which also involves financializing university governance. Many states have retrenched investments that had once underwritten universities’ flourishing and their moves toward massification. Tensions have deepened over who should pay for rising costs, exacerbated in an era of increasing status competition via higher education. In the face of such challenges globally, which alternatives exist? A prominent possibility, pioneered in Germany in the 1970s, are “dual study” programs offered by several organizational forms, from vocational academies to universities of applied sciences. Such hybrid programs fully integrate phases of higher education study and paid work in firms. Another potential advantage of apprenticeship training being offered in conjunction with higher education is that this would boost the reputation of apprenticeships overall. The German experience indicates that the attractiveness of the apprenticeship training system as a whole can be bolstered when it offers a viable pathway also for those individuals with a traditional university entrance certificate. If these students seriously consider and choose advanced work-based higher education, this may well increase the standing of apprenticeship training among students, their families, and employers. Thus, dual study programs provide an innovative model for policymaking and implementation. Especially when considering strategies to improve skill formation overall, to reduce the costs individuals must bear in attaining higher education, and to improve the fit between the expectations of employers and potential employees regarding skill formation, dual study programs excel. The origins and contemporary developments in work-based higher education in Germany offer lessons and inspiration for Anglophone countries, with their strong and differentiated higher education systems, to further bolster study programs coordinated with firms. [less ▲]

Detailed reference viewed: 202 (9 UL)
Full Text
Peer Reviewed
See detailThe induced metric on the boundary of the convex hull of a quasicircle in hyperbolic and anti de Sitter geometry
Bonsante, Francesco; Danciger, Jeff; Maloni, Sara et al

in Geometry and Topology (in press)

Celebrated work of Alexandrov and Pogorelov determines exactly which metrics on the sphere are induced on the boundary of a compact convex subset of hyperbolic three-space. As a step toward a ... [more ▼]

Celebrated work of Alexandrov and Pogorelov determines exactly which metrics on the sphere are induced on the boundary of a compact convex subset of hyperbolic three-space. As a step toward a generalization for unbounded convex subsets, we consider convex regions of hyperbolic three-space bounded by two properly embedded disks which meet at infinity along a Jordan curve in the ideal boundary. In this setting, it is natural to augment the notion of induced metric on the boundary of the convex set to include a gluing map at infinity which records how the asymptotic geometry of the two surfaces compares near points of the limiting Jordan curve. Restricting further to the case in which the induced metrics on the two bounding surfaces have constant curvature K∈[−1,0) and the Jordan curve at infinity is a quasicircle, the gluing map is naturally a quasisymmetric homeomorphism of the circle. The main result is that for each value of K, every quasisymmetric map is achieved as the gluing map at infinity along some quasicircle. We also prove analogous results in the setting of three-dimensional anti de Sitter geometry. Our results may be viewed as universal versions of the conjectures of Thurston and Mess about prescribing the induced metric on the boundary of the convex core of quasifuchsian hyperbolic manifolds and globally hyperbolic anti de Sitter spacetimes. [less ▲]

Detailed reference viewed: 48 (3 UL)
Full Text
Peer Reviewed
See detailThe effect of risk disclosure on analyst following
Derouiche, Imen UL; Muessig, Anke UL; Weber, Véronique UL

in European Journal of Finance (in press)

Prior research shows that financial analysts play an important information intermediary role in France. This study extends earlier research to examine the effect of risk disclosure on the number of ... [more ▼]

Prior research shows that financial analysts play an important information intermediary role in France. This study extends earlier research to examine the effect of risk disclosure on the number of analysts following listed firms. Using a unique dataset of French firms on the 120 SBF index over 2007−2015, the results show a positive and significant relation between risk disclosure and analyst following, suggesting that firms having greater risk disclosure attract more financial analysts. These findings provide empirical support to the argument that analysts incur lower costs of information gathering in firms with greater risk disclosure. The demand for analyst services is also more valuable in these firms, given their potentially high exposure to risks, implying greater analyst following. Overall, our results are in line with prior literature highlighting that analysts’ activities complement annual report disclosures and, generally, corporate disclosures. [less ▲]

Detailed reference viewed: 76 (8 UL)
Full Text
Peer Reviewed
See detailOn Rational Entailment for Propositional Typicality Logic
Booth, Richard; Casini, Giovanni UL; Meyer, Thomas et al

in Artificial Intelligence (in press)

Propositional Typicality Logic (PTL) is a recently proposed logic, ob- tained by enriching classical propositional logic with a typicality opera- tor capturing the most typical (alias normal or ... [more ▼]

Propositional Typicality Logic (PTL) is a recently proposed logic, ob- tained by enriching classical propositional logic with a typicality opera- tor capturing the most typical (alias normal or conventional) situations in which a given sentence holds. The semantics of PTL is in terms of ranked models as studied in the well-known KLM approach to preferen- tial reasoning and therefore KLM-style rational consequence relations can be embedded in PTL. In spite of the non-monotonic features introduced by the semantics adopted for the typicality operator, the obvious Tarskian definition of entailment for PTL remains monotonic and is therefore not appropriate in many contexts. Our first important result is an impossibil- ity theorem showing that a set of proposed postulates that at first all seem appropriate for a notion of entailment with regard to typicality cannot be satisfied simultaneously. Closer inspection reveals that this result is best interpreted as an argument for advocating the development of more than one type of PTL entailment. In the spirit of this interpretation, we in- vestigate three different (semantic) versions of entailment for PTL, each one based on the definition of rational closure as introduced by Lehmann and Magidor for KLM-style conditionals, and constructed using different notions of minimality. [less ▲]

Detailed reference viewed: 71 (0 UL)
Full Text
Peer Reviewed
See detailThe effects of age stereotypes on physical and mental health are mediated by self-perceptions of aging
Brothers, Allyson; Kornadt, Anna Elena UL; Nehrkorn-Bailey, Abigail et al

in Journals of Gerontology. Series B, Psychological Sciences and Social Sciences (in press)

Detailed reference viewed: 35 (1 UL)
Full Text
Peer Reviewed
See detailIncome and Wealth Volatility: Evidence from Italy and the U.S. in the Past Two Decades
Menta, Giorgia UL; Wolff, Edward; d'ambrosio, Conchita UL

in Journal of Economic Inequality (in press)

Income volatility and wealth volatility are central objects of investigation for the literature on income and wealth inequality and dynamics. Here we analyse the two concepts in a comparative perspective ... [more ▼]

Income volatility and wealth volatility are central objects of investigation for the literature on income and wealth inequality and dynamics. Here we analyse the two concepts in a comparative perspective for the same individuals in Italy and the U.S. over the last two decades. We find that in both countries wealth volatility reaches significantly higher values than income volatility, the effect being mostly driven by changes in the market value of real estate assets. We also show that there is more volatility in both dimensions in the U.S. and that the overall trend in both countries is increasing over time. We conclude by exploring volatility in consumption. [less ▲]

Detailed reference viewed: 81 (5 UL)
Full Text
Peer Reviewed
See detailConcentration of the Intrinsic Volumes of a Convex Body
Lotz, Martin; McCoy, Michael B.; Nourdin, Ivan UL et al

in Geometric Aspects of Functional Analysis (in press)

Detailed reference viewed: 81 (5 UL)
Full Text
Peer Reviewed
See detailDon't Trust Me, Test Me: 100% Code Coverage for a 3rd-party Android App
Pilgun, Aleksandr UL

in Pilgun, Aleksandr (Ed.) Don't Trust Me, Test Me: 100% Code Coverage for a 3rd-party Android App (in press)

The incompleteness of 3rd-party app testing is an accepted fact in Software Engineering. This issue makes it impossible to verify the app functionality and to confirm its safety to the end-user. To solve ... [more ▼]

The incompleteness of 3rd-party app testing is an accepted fact in Software Engineering. This issue makes it impossible to verify the app functionality and to confirm its safety to the end-user. To solve this problem, enterprises developed strict policies. A company, willing to use modern apps, may perform an expensive security analysis, rely on trust or forbid the app. These strategies may lead companies to high direct and indirect spending with no guarantee of safety. In this work, we present a novel approach, called Dynamic Binary Shrinking, that allows a user to review app functionality and leave only tested code. The shrunk app produces 100% instruction coverage on observed behaviors and in this way guarantees the absence of unexplored, and therefore, potentially malicious code. On our running examples, we demonstrate that apps use less than 20% of the codebase. We developed an approach and the ACVCut tool to shrink Android apps towards the executed code. Repository — http://github.com/pilgun/acvcut. [less ▲]

Detailed reference viewed: 101 (7 UL)
Full Text
See detailInternationales und Europäisches Steuerrecht
Sinnig, Julia UL

in Taeger, Jürgen; Pohle, Jan; Kilian, Wolfgang (Eds.) et al Computerrechts-Handbuch - Informationstechnologie in der Rechts- und Wirtschaftspraxi (in press)

Detailed reference viewed: 69 (0 UL)
Full Text
Peer Reviewed
See detail"[I]ch bin gerne da, wo es gärt" Feridun Zaimoglu im Gespräch mit Natalie Bloch über seine Theaterarbeit
Bloch, Natalie UL

in Zeitschrift für Interkulturelle Germanistik (in press), 10(2), 97-105

Detailed reference viewed: 57 (1 UL)
Full Text
Peer Reviewed
See detailThe EU Administrative Institutions, Their Law and Legal Scholarship
Mendes, Joana UL

in Cane, Peter; Hoffman, Herwig; Lindseth, Peter (Eds.) Oxford Handbook on Comparative Administrative Law (in press)

The chapter approaches the EU administrative institutions as catalysts of the development of administrative law of the European Union. As a chapter of the Oxford Handbook on Comparative Administrative Law ... [more ▼]

The chapter approaches the EU administrative institutions as catalysts of the development of administrative law of the European Union. As a chapter of the Oxford Handbook on Comparative Administrative Law, it explains the main traits of those institutions, how legal scholarship has portrayed them and how it has addressed the core aspects of their legal regimes. Furthermore, it traces the emergence and current state of EU administrative law, characterising the different roles comparative administrative law has had at different stages. It highlights the initial dissonance between the specificities of the EU administrative institutions and the state-matrix of general principles that were developed on the basis of functional comparison; the role of legal scholarship in shaping EU administrative law, in its efforts to give effect to an “utopia” (Chiti, 2007) of an integrated administration constitutionally framed by general principles and fundamental rights; the limits of resorting to comparative administrative law in the context of EU integration and, briefly, the crossroads at which EU administrative law currently stands. [less ▲]

Detailed reference viewed: 108 (2 UL)
Full Text
See detailReinforcing citizens’ participation by reforming European commission public consultations
Kies, Raphaël UL

in Alemanno, Alberto; Oregan, James (Eds.) Democratic Participation in a Citizen's Europe: What next for the EU? (in press)

In this chapter, I would like to draw some lessons from the failed attempts of democratization of the EU by proposing some guidelines that should be followed in order to envision a realistic deliberative ... [more ▼]

In this chapter, I would like to draw some lessons from the failed attempts of democratization of the EU by proposing some guidelines that should be followed in order to envision a realistic deliberative and inclusive transformation of the EU-decision making process. By following their spirits, I will propose an ambitious renovation of the public consultation regime of the EU Commission, the only institutionalized system of public consultation enshrined in the EU Treaties that however most of the citizens are not aware of. This is an idea that I first presented in at the conference at the World Bank (Kies 2016) and that has since then been discussed and presented in the report commissioned by the European Economic and Social Committee (Lironi and Peta 2017), the European Parliament (Korthagen et al. 2018) and is presently discussed within the European Court of Auditors. [less ▲]

Detailed reference viewed: 34 (3 UL)