• A
  • A
  • A
  • ABC
  • ABC
  • ABC
  • А
  • А
  • А
  • А
  • А
Regular version of the site
Of all publications in the section: 3 551
Sort:
by name
by year
Working paper
Vladimir L. Popov. arxiv.org. math. Cornell University, 2014. No. 1409.6330.
A "rational" version of the strengthened form of the Commuting Derivation Conjecture, in which the assumption of commutativity is dropped, is proved. A systematic method of constructing in any dimension greater than 3 the examples answering in the negative a question by M. El Kahoui is developed.
Added: Sep 24, 2014
Working paper
Positselski L. arxiv.org. math. Cornell University, 2011. No. 1012.3735.
We propose a construction of a tensor exact category F_X^m of Artin-Tate motivic sheaves with finite coefficients Z/m over an algebraic variety X (over a field K of characteristic prime to m) in terms of etale sheaves of Z/m-modules over X. Among the objects of F_X^m, in addition to the Tate motives Z/m(j), there are the cohomological relative motives with compact support M_cc^m(Y/X) of varieties Y quasi-finite over X. Exact functors of inverse image with respect to morphisms of algebraic varieties and direct image with compact supports with respect to quasi-finite morphisms of varieties Y\to X act on the exact categories F_X^m. Assuming the existence of triangulated categories of motivic sheaves DM(X,Z/m) over algebraic varities X over K and a weak version of the "six operations" in these categories, we identify F_X^m with the exact subcategory in DM(X,Z/m) consisting of all the iterated extensions of the Tate twists M_cc^m(Y/X)(j) of the motives M_cc^m(Y/X). An isomorphism of the Z/m-modules Ext between the Tate motives Z/m(j) in the exact category F_X^m with the motivic cohomology modules predicted by the Beilinson-Lichtenbaum etale descent conjecture (recently proven by Voevodsky, Rost, et al.) holds for smooth varieties X over K if and only if the similar isomorphism holds for Artin-Tate motives over fields containing K. When K contains a primitive m-root of unity, the latter condition is equivalent to a certain Koszulity hypothesis, as it was shown in our previous paper.
Added: Feb 20, 2014
Working paper
Nenko A. (., Basov N. Working Papers of Centre for German and European Studies (CGES). ISSN 1860-5680. SPbSU, University of Bielefeld, Centre for German and European Studies (CGES), 2013. No. 8.
Artists are among the key knowledge-generating actors in the city space,  particularly when they join in collectives. Knowledge creation in artistic groups  goes in constant (re-)interpretation of the essence of art, discussions on the  themes and formats for artworks, continuous interaction during collective  creative processes and the presentation of artworks in the city space. This  study explores the opportunities for semantic network analysis to shed light on  the knowledge structures underlying the creative practices of artistic  communities. Combining a set of quantitative and qualitative techniques, we  study the case of the artistic community “La Escocesa” located in Barcelona,  Spain. To map semantic networks as relations between co-occurring concepts,  texts of semi-structured interviews with the artists are used.1  Interpretation of  the structures is given with regard to the qualitative data collected during a field  study, and links the knowledge structures revealed to the peculiar  characteristics of the creative processes in the community, such as positioning  and identification, format of creative practices, engagement of publics,  community localization in a co-habilitation space and the broader urban  context. 
Added: Oct 21, 2014
Working paper
Brown F., Levin A. math. arxive. Cornell University, 2013. No.  1110.6917 [.
Abstract. We study the de Rham fundamental group of the configuration sp ace of several  marked points on a complex elliptic curve, and define multiple elliptic polylogarithms. These are multivalued functions with unipotent monodromy, and are constructed by a general averaging proce dure. We show that all iterated integrals on this configuration space can be expressed in terms of these functions.
Added: Oct 4, 2013
Working paper
Fenogenova A., Kuzmenko E. Linguistics. WP BRP. НИУ ВШЭ, 2016
Learner corpora constitute an effective resource for specialists in fields of second language acquisition, foreign language teaching and corpus linguistics. They tend to get significant scholarly help from statistical tools of various kinds. However, for valuable usage of a corpus it should provide convenient and powerful tools for searching and manipulating data. In this paper we focus on searching tools, presented in \textit{Russian Error-Annotated Learner English Corpus (REALEC)}, report our attempts to improve the format of the searching tools in our corpora. We also provide evidences that database search is much more efficient than common text search and demonstrate that search functionality in corpora is of great importance for research efficiency and extensive facilities.
Added: Dec 14, 2016
Working paper
Shitov Y. arxiv.org. math. Cornell University, 2014. No. 1406.2601.
We construct a nontrivial identity which holds in the semigroup of tropical 3-by-3 matrices.
Added: Mar 14, 2015
Working paper
V. V. Lebedev. arxiv.org. math. Cornell University, 2016. No. 1603.04539.
It is well--known that certain properties of continuous functions on the circle $\mathbb T$, related to the Fourier expansion, can be improved by a change of variable, i.e., by a homeomorphism of the circle onto itself. One of the results in this area is the Jurkat--Waterman theorem on conjugate functions, which improves the classical Bohr--Pal theorem.  In the present work we provide a short and technically very simple proof of the Jurkat--Waterman theorem. Our approach yields a stronger result.
Added: Nov 10, 2016
Working paper
Kuznetsov A. G. arxiv.org. math. Cornell University, 2013
A counterexample to the Jordan-H\"older property for semiorthogonal decompositions of derived categories of smooth projective varieties was constructed by B\"ohning, Graf von Bothmer and Sosna. In this short note we present a simpler example by realizing Bondal's quiver in the derived category of a blowup of the projective space.
Added: Jul 1, 2013
Working paper
Prokhorov Y. math. arxive. Cornell University, 2016
The aim of this short note is to give a simple proof of the non-rationality of the double cover of the three-dimensional projective space branched over a sufficiently general quartic.
Added: May 16, 2016
Working paper
Shulgin A. G. Economics. EC. Высшая школа экономики, 2017. No. 170.
This paper constructs a theoretical general equilibrium model for exchange rate determination in a small open commodity exporting economy based on an imperfect capital market a la Gabaix-Maggiori and appropriate for estimation on high frequency data and could be used for the evaluation of sterilized intervention effectiveness. To find empirical confirmation of the theoretical setup validity I use Russian daily statistics to estimate the model and investigate the reaction of the Russian ruble-US dollar exchange rate to sterilized interventions in the form of foreign currency repo auctions conducted by the Bank of Russia in the period of 2014-2017. I also estimate a vector error correction model on the same dataset and use it as important empirical benchmark for the theoretical model. The empirical analysis revealed a temporary statistically significant effect of sterilized intervention on exchange rate level, which peaked eight working days after the auction day. The combination of theoretical and empirical approaches demonstrates the effectiveness of the portfolio and the ineffectiveness of signalling channels in the transmission mechanism of the sterilized intervention instrument in Russian case
Added: Oct 16, 2017
Working paper
Abankina T., Derkachev P., Filatova L. et al. Management. MAN. Высшая школа экономики, 2015. No. WP BRP 43/MAN/2015.
Accessibility is a key priority of public policy in the social sphere, a necessary condition to ensure equal opportunities and cultural participation. Analysis of the international practice reveals that the issue of accessibility has two aspects - objective and subjective. Regression models were used to conduct empirical analysis of the impact of economic factors on the museum attendance. The factor analysis of the data for the period of 2010-2012 conducted with the principle component method allowed to identify five factors. As a result, we estimated the impact of each factor on the museum attendance.
Added: Dec 3, 2015
Working paper
Ducomet B., Zlotnik A. A., Romanova A. V. arxiv.org. math. Cornell University, 2013. No. 1309.7280 .
An initial-boundary value problem for the $n$-dimensional ($n\geq 2$) time-dependent Schrödinger equation in a semi-infinite (or infinite) parallelepiped is considered. Starting from the Numerov-Crank-Nicolson finite-difference scheme, we first construct higher order scheme with splitting space averages having much better spectral properties for $n\geq 3$. Next we apply the Strang-type splitting with respect to the potential and, third, construct discrete transparent boundary conditions (TBC). For the resulting method, the uniqueness of solution and the unconditional uniform in time $L^2$-stability (in particular, $L^2$-conservativeness) are proved. Owing to the splitting, an effective direct algorithm using FFT (in the coordinate directions perpendicular to the leading axis of the parallelepiped) is applicable for general potential. Numerical results on the 2D tunnel effect for a P\"{o}schl-Teller-like potential-barrier and a rectangular potential-well are also included.
Added: Oct 1, 2013
Working paper
Siliverstov B., Smirnov S. V., Tsukhlo S. KOF Working Papers. KOF. KOF Swiss Economic Institute, 2012. No. 306.
This study investigates usefulness of business tendency surveys in industrial sector for out-of-sample prediction of growth of industrial production in Russia. A special attention is paid to performance of survey-augmented models during the recent Great Recession 2008/2009. Using the real-time data vintages of the index of industrial production in Russia we conclude that the use of surveys positively contributes to boosting forecast accuracy of industrial production compared with forecasts based on a benchmark univariate autoregressive model.
Added: Apr 12, 2013
Working paper
Pikalova A. G., Korobeynikova M. N. SEARCH Working Paper. WP4. Университет Барселоны, 2013. No. 27.
The European Neighbourhood Policy (ENP) remains the basis on which the EU works with its neighbours to achieve the closest possible political association and the greatest possible degree of economic integration. Knowledge creation precisely research and technological development (RTD) is a shaping basis of up-to-date economy and measures focused on responding to the global challenges. International RTD cooperation and transfer of knowledge is essential to reinforce research capacity of involved parties, to share respective resources and risks as well as to lay the foundation for joint innovative activities. EU RTD programmes are open for participation of scientists from any countries world-wide including the EECA countries and Russia in cooperation with the European researchers. The EU policy actively promotes integration of the EECA and Russian scientists into the European Research Area. The present paper offers assessment of EU-EECA and EU-Russia cooperation within FP5-7 (1998-2012) classified by country, by discipline and by type of organisation. The conducted assessment is based on the collection and systematisation of data on joint EU-EECA and EU-Russia projects extracted from the EU CORDIS Project database. The synergy with the FP7 IncoNet EECA and FP6 SCOPE-EAST projects has been used. The part on Russian participation in projects within FP7 includes data presented by the European Commission at the workshops. The Case-study of 5 functioning EU-EECA thematic research networks was carried out via a specially elaborated questionnaire addressed to EU and EECA partners of ongoing research projects under the 7th EU Framework RTD Programme. The Case-study contributed to analysis of the effects of EU-EECA thematic research networks, formed in the course of FP7 projects including identification of added value, success stories and barriers to EU-EECA collaboration. It helped to understand what barriers scientists face implementing joint research projects under EU Framework RTD Programme.
Added: Jul 31, 2014
Working paper
Kosareva N., Polidi T. D., Puzanov A. et al. Urban and Transportation Studies. WP BRP 03/URB/2016. HSE Working Papers, 2016
Russian cities currently feel the utmost need both for improving the affordability of housing and upgrading the quality and enhancing the beautification of the urban environment, developing public spaces, expanding the diversity of forms of housing tenure for different categories of citizen. Implementation of the housing policy objectives necessitates a considerable update of urban planning policy which is currently characterized by minimum urban planning regulations and inadequate enforcement of those in place. Urban development regulation and land use system remains a source of ‘administrative rent’ and appears to be unable to ensure a transparent legal framework for investors and developers, which is replaced by high administrative barriers. The paper reviews the current state of housing and urban planning policies in Russia, the practice of reconciling the goals, objectives and instruments of the foregoing policies. Housing and urban planning policies both at federal and local levels are described and case studies of inconsistencies in implementation of housing and urban planning policies in Russian cities are analyzed. The paper also sets forth the proposals on how to streamline housing and urban planning policies with a view to improving the affordability of housing and upgrading the quality of urban environment.
Added: Feb 19, 2016
Working paper
Lazareva O., Rachinsky A., Stepanov S. CEFIR / NES Working Paper. Центр экономических и финансовых исследований и разработок в российской экономической школе, Российская экономическая школа, 2007. No. 103.
Added: Nov 25, 2013
Working paper
Dranev Y., Babuskin M. Financial Economics. FE. Высшая школа экономики, 2014
This work contributes to the literature on exchange-rate exposure in emerging markets. We studied datasets of exchange-listed companies from four BRIC countries and discovered that exchange rate movements in the US dollar and euro affected more than 10% of these firms between 2003 and 2013. The most interesting finding of this research is that stock returns behaved differently with increasing and decreasing currency rates. For capturing the asymmetric relationship of stock and exchange rate movements, we applied a nonlinear dynamic model, which significantly improved our results compared to the empirical findings of simple versions of the Adler Dumas (1984) and Jorion (1990) models. We studied determinants of exposure to positive and negative currency movements separately. Although significant determinants in both cases were mostly similar, their weights were different. For example, the ratio of export sales was asymmetrically correlated to exchange rate exposures for all countries except Russia. For a better understanding of the sources of asymmetry in exchange rate exposure, we separately studied the positive and negative coefficients of currency exposure from the non-asymmetric model. This was never done before and natural in a way that determinants should affect positive and negative currency exposures differently. We found evidence of the contrasting impact of export sales and foreign debt in both cases.
Added: Feb 6, 2014
Working paper
Vyacheslav V. Chistyakov. Functional Analysis. arXiv [math.FA]. Cornell University, NY, USA, 2019. No. 1901.09722.
Under certain initial conditions, we prove the existence of set-valued selectors of univariate compact-valued multifunctions of bounded (Jordan) variation when the notion of variation is defined taking into account only the Pompeiu asymmetric excess between compact sets from the target metric space. For this, we study subtle properties of the directional variations. We show by examples that all assumptions in the main existence result are essential. As an application, we establish the existence of set-valued solutions $X(t)$ of bounded variation to the functional inclusion of the form $X(t)\subset F(t,X(t))$ satisfying the initial condition $X(t_0)=X_0$.  
Added: Jan 29, 2019
Working paper
Ivan Cheltsov, Rubinstein Y. A. arxiv.org. math. Cornell University, 2013
Motivated by the study of Fano type varieties we define a new class of log pairs that we call asymptotically log Fano varieties and strongly asymptotically log Fano varieties. We study their properties in dimension two under an additional assumption of log smoothness, and give a complete classification of two dimensional strongly asymptotically log smooth log Fano varieties. Based on this classification we formulate an asymptotic logarithmic version of Calabi's conjecture for del Pezzo surfaces for the existence of K\"ahler--Einstein edge metrics in this regime. We make some initial progress towards its proof by demonstrating some existence and non-existence results, among them a generalization of Matsushima's result on the reductivity of the automorphism group of the pair, and results on log canonical thresholds of pairs. One by-product of this study is a new conjectural picture for the small angle regime and limit which reveals a rich structure in the asymptotic regime, of which a folklore conjecture concerning the case of a Fano manifold with an anticanonical divisor is a special case.
Added: Dec 27, 2013
Working paper
Ulyanov V. V., Goetze F., Naumov A. Collaborative Research Centre 701, Bielefeld University. 15025. CRC 701, Bielefeld University, Bielefeld, Germany, 2015. No. 15025.
In this paper we consider asymptotic expansions for a class of sequences of symmetric functions of many variables. Applications to classical and free probability theory are discussed.
Added: Jul 13, 2015
Working paper
V.L. Chernyshev, Tolchennikov A. arxiv.org. math. Cornell University, 2014. No. 1403.0263.
We study a topological space obtained from a graph by replacing vertices with smooth Riemannian manifolds, i.e. a decorated graph. We construct a semiclassical asymptotics of the solutions of Cauchy problem for a time-dependent Schroedinger equation on a decorated graph with a localized initial function. The main term of our asymptotic solution at an arbitrary finite time is the sum of Gaussian packets and generalized Gaussian packets. We study the number of such packets as time goes to infinity. We prove asymptotic estimations for this number for the following decorated graphs: cylinder with a segment, two dimensional torus with a segment, three dimensional torus with a segment.
Added: Mar 4, 2014