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Working paper

This paper demonstrates that even established and verified facts of agreements among producers are not a sufficient condition for cartel identification and, as a consequence, prosecution of agreement participants. Such requires looking at institutional details and the wider context of these and similar appearances or occurrences of documents and actions when qualifying the actions of market participants and their effects. This paper discusses a recent antitrust case brought against Russian manufacturers of large diameter pipes (LDPs) that examined supposedly abusive practices by these firms that were contrary to the law on the Protection of Competition, which prohibits market division. An analysis of the materials in this case using modern economic theory indicates that the presence of collusion is inconsistent with the active participation of the main consumer of LDPs in that agreement. The chosen format for the cooperation between pipe manufacturing companies and OJSC Gazprom, namely indicative planning, may be explained from the perspective of reducing contract risk in an environment characterized by large-scale private investments.

Added: Feb 12, 2014

Working paper

We introduce a new asset pricing model to account for risk asymmetrically in a very natural way. Assuming asymmetric investor behavior we develop a utility function similar to a quadratic utility but include a colog measure for capturing risk attitude. Asymmetry in investor preferences follows the asymmetric relationships between asset and market returns in equilibrium. Moreover the local version of the model depends on the characteristics of domestic markets, which is reflected in the different relationship between asset and market returns. We test the model in the Russian and South African markets and show that market premium in the Russian market is higher than in the South African market.

Added: Jan 24, 2014

Working paper

Added: Nov 2, 2012

Working paper

Added: Sep 2, 2018

Working paper

Blokh A., Oversteegen L., Ptacek R. et al. arxiv.org. math. Cornell University, 2014

To construct a model for a connectedness locus of polynomials of degree $d\ge
3$ (cf with Thurston's model of the Mandelbrot set), we define \emph{linked}
geolaminations $\mathcal{L}_1$ and $\mathcal{L}_2$. An \emph{accordion} is
defined as the union of a leaf $\ell$ of $\mathcal{L}_1$ and leaves of
$\mathcal{L}_2$ crossing $\ell$. We show that any accordion behaves like a gap
of one lamination and prove that the maximal \emph{perfect} (without isolated
leaves) sublaminations of $\mathcal{L}_1$ and $\mathcal{L}_2$ coincide.
In the cubic case let $\mathcal{D}_3\subset \mathcal{M}_3$ be the set of all
\emph{dendritic} (with only repelling cycles) polynomials. Let $\mathcal{MD}_3$
be the space of all \emph{marked} polynomials $(P, c, w)$, where $P\in
\mathcal{D}_3$ and $c$, $w$ are critical points of $P$ (perhaps, $c=w$). Let
$c^*$ be the \emph{co-critical point} of $c$ (i.e., $P(c^*)=P(c)$ and, if
possible, $c^*\ne c$). By Kiwi, to $P\in \mathcal{D}_3$ one associates its
lamination $\sim_P$ so that each $x\in J(P)$ corresponds to a convex polygon
$G_x$ with vertices in $\mathbb{S}$. We relate to $(P, c, w)\in \mathcal{MD}_3$
its \emph{mixed tag} $\mathrm{Tag}(P, c, w)=G_{c^*}\times G_{P(w)}$ and show
that mixed tags of distinct marked polynomials from $\mathcal{MD}_3$ are
disjoint or coincide. Let $\mathrm{Tag}(\mathcal{MD}_3)^+ =
\bigcup_{\mathcal{D}_3}\mathrm{Tag}(P,c,w)$. The sets $\mathrm{Tag}(P, c, w)$
partition $\mathrm{Tag}(\mathcal{MD}_3)^+$ and generate the corresponding
quotient space $\mathrm{MT}_3$ of $\mathrm{Tag}(\mathcal{MD}_3)^+$. We prove
that $\mathrm{Tag}:\mathcal{MD}_3\to \mathrm{MT}_3$ is continuous so that
$\mathrm{MT}_3$ serves as a model space for $\mathcal{MD}_3$.

Added: Feb 11, 2015

Working paper

As noticed by R. Kulkarni, the conjugacy classes of subgroups of the modular group correspond bijectively to bipartite cuboid graphs. We'll explain how to recover the graph corresponding to a subgroup $G$ of $PSL_2(\mathbb{Z})$ from the combinatorics of the right action of $PSL_2(\mathbb{Z})$ on the right cosets $G\setminus PSL_2(\mathbb{Z})$ This gives a method of constructing nice fundamental domains (which Kulkarni calls "special polygons") for the action of $G$ on the upper half plane. For the classical congruence subgroups $\Gamma(N),\Gamma_0(N),\Gamma_1(N)$ etc. the number of operations the method requires is the index times something that grows not faster than a polynomial in $log(N)$. We also give algorithms to locate a given element of the upper half-plane on the fundamental domain and to write a given element of $G$ as a product of independent generators.

Added: Apr 4, 2014

Working paper

Added: Nov 2, 2012

Working paper

This paper analyses the influence of different combinations of work and study on academic achievement among university students of Yaroslavl region in Russia. The data was collected during the first wave of longitudinal research on the educational and occupational trajectories of graduates of schools and universities conducted by the Institute of Education, Higher School of Economics, Moscow in 2009. The sample consists of 1474 4th and 5th year university students. Five work-study types are defined on the basis of two variables: work schedule and work relatedness to specialty: full-time work outside the specialty field, part-time work outside the specialty field; full-time work in the specialty field, part-time work in the specialty field; and not working during university studies. The results show that working outside the specialty field (full-time or part-time) has a negative impact on academic achievement, whereas the other work-study types do not have any significant effect. The results partly support our hypothesis that different work-study combinations influence academic achievement in different ways and that job relatedness to the academic specialty is a significant characteristic in defining the influence. The paper contributes to the research field of studying attributes of student employment which are responsible for different effects on academic achievement

Added: Dec 9, 2014

Working paper

We study the structure of online discussions in order to uncover latent communities of socially important debate. Our research reveals that discussion communities defined by mutual commenting in the Russian language blogosphere are centered mainly around blog authors as opinion leaders and, to a lesser extent, around a shared topic or topics. We have derived these conclusions from the dataset of 17386 full text posts written by top 2000 LiveJournal bloggers and over 520,000 comments that result in about 4.5 million edges in the network of co-commenting

Added: Jan 14, 2014

Working paper

In recent paper of Falkovich and Levitov it was shown, that geometry of separatrixes for viscous electronic flow in graphene is sensitive to boundary conditions. Here we discover theis relation in details. Also we propose, how boundary conditions could be probed experimentally, using weak magnetic field and observed features of separatrixes.

Added: Apr 4, 2018

Working paper

Added: Apr 5, 2017

Working paper

The paper explores the composition of researchers' skillsets in an innovation-driven environment from the perspective of employers. The authors analyze the relation between skills requirements described in job advertisements for researchers and the presumed innovation culture of companies. The study is based on job advertisements content analysis and in-depth interviews with chiefs of research and development companies. It uses biotechnology industry as an example as it is one of the fastest-growing and innovation-driven sectors globally. Authors used data from Russian, as well as Canadian, UK and USA job search engines to consider international context. Empirical findings demonstrated that skills composition stress on hard skills more frequently and detailed, while soft skills are often a "must have without saying". The same is for digital skills that are assumed to be essential in high-tech companies globally and therefore not fully specified in job ads. There is a certain mismatch between skills presented in the ads and articulated in the interviews as employers tend to demonstrate innovation-friendly company culture for possible applicants. The present paper enriches literature on skills assessment, giving comprehensive lists of biotech skills in-demand divided into soft and hard categories. In addition, it provides the new insight into employee skills articulated by the companies as a strong element of organizational innovation climate.

Added: Oct 13, 2017

Working paper

Purpose – We aim to better understand the factors that shape the intensity and perceived effectiveness of communication between heads of the manufacturing units of multinational corporations (MNCs). Design/methodology/approach – A series of interviews and a medium-size survey among subsidiary executives were conducted. Findings – The intensity of most inter-unit communication channels depends on the speed and magnitude of the changes in products and production technologies that manufacturing subsidiaries experience. For newly established subsidiaries, mastering inter-unit communication channels precedes inter-unit cooperation. At the same time, different types of inter-unit cooperation strengthen specific channels of inter-unit communication. The assessment of the efficiency of a communication channel with high media richness strongly correlates to the intensity of its use. Research limitations/implications – The results are confined to one country where the manufacturing subsidiaries of MNCs were surveyed. Further research is needed for the general applicability of these findings to subsidiaries in several countries or regions. Practical implications – As inter-unit communication precedes inter-unit cooperation for newly established subsidiaries, headquarters and more experienced subsidiaries should promote the use of communication channels with high media richness. Several suggestions on how to perform such a task are proposed. Originality/value – This paper contributes to the ongoing discussion concerning inter-unit communication and knowledge transfer within MNCs.

Added: May 4, 2015

Working paper

Added: Dec 15, 2017

Working paper

Compact difference schemes for weakly-nonlinear parabolic and Schrodinger-type equations and systems

The implicit compact finite-difference scheme was developed for evolutionary partial differential parabolic and Schrodinger-type equations and systems with a weak nonlinearity. To make a temporal step of the compact implicit scheme we need to solve a non-linear system. We use for this step a simple explicit difference scheme and then Newton - Raphson iterations, which are implemented by the double-sweep method. Numerical experiments confirm the 4-th order of an algorithm. The Richardson extrapolation improves it up to the 6-th order.

Added: Dec 15, 2017

Working paper

Essential dimension of a family of complex manifolds is the dimension of the image of its base in the Kuranishi space of the fiber. We prove that any family of hyperk\"ahler manifolds over a compact simply connected base has essential dimension not greater than 1. A similar result about families of complex tori is also obtained.

Added: Sep 23, 2016

Working paper

Campana F., Demailly J.,

. arxiv.org. math. Cornell University, 2013
We prove that any compact K\"ahler 3-dimensional manifold which has no non-trivial complex subvarieties is a torus. This is a very special case of a general conjecture on the structure of 'simple manifolds', central in the bimeromorphic classification of compact K\"ahler manifolds. The proof follows from the Brunella pseudo-effectivity theorem, combined with fundamental results of Siu and of the second author on the Lelong numbers of closed positive (1,1)-currents, and with a version of the hard Lefschetz theorem for pseudo-effective line bundles, due to Takegoshi and Demailly-Peternell-Schneider. In a similar vein, we show that a normal compact and K\"ahler 3-dimensional analytic space with terminal singularities and nef canonical bundle is a cyclic quotient of a simple non-projective torus if it carries no effective divisor. This is a crucial step to complete the bimeromorphic classification of compact K\"ahler 3-folds.

Added: May 13, 2013

Working paper

Ornea L.,

arxiv.org. math. Cornell University, 2015
A locally conformally Kahler manifold is a Hermitian manifold (M,I,ω) satisfying dω=θ∧ω, where θ is a closed 1-form, called the Lee form of M. It is called pluricanonical if ∇θ is of Hodge type (2,0)+(0,2), where ∇ is the Levi-Civita connection, and Vaisman if ∇θ=0. We show that a compact LCK manifold is pluricanonical if and only if the Lee form has constant length and the Kahler form of its covering admits an automorphic potential. Using a degenerate Monge-Ampere equation and the classification of surfaces of Kahler rank one, due to Brunella, Chiose and Toma, we show that any pluricanonical metric on a compact manifold is Vaisman. Several errata to our previous work are given in the last Section.

Added: Dec 5, 2015

Working paper

In the era of the knowledge economy intangibles are recognized by investors as pivotal value drivers. Previous research of portfolio forming methods based on intangibles is limited by taking into account only the quantity of intangibles. We propose a tool to select companies able to create knowledge (in contrast to the absorption of knowledge), which is a quality of intangibles. To test whether these abilities are results of skill we implement a bootstrap procedure. It shows that only 22% of companies have the skills to create knowledge, but all of them are characterized by positive results of knowledge creation. To show the practical implications of the proposed approach selected companies are combined in a portfolio. This portfolio demonstrates a higher cumulative return, Sharpe ratio and drawdown than S&P500. We also find the increasing importance of intangibles for investors during the crisis. While exogenous shocks influenced both creators and absorbers, we found that intangibles create an obstacle to a sharp drop of market value.

Added: Feb 6, 2014

Working paper

This article focuses on the development of antitrust policy in transition economies in the context of preventing explicit and tacit collusion. Experience of BRICS, Kazakhstan, Ukraine and CEE countries (Bulgaria, Hungary, Latvia, Lithuania, Poland, Romania, Slovakia, Slovenia, Czech Republic, Estonia) in the creation of antitrust institutions was analyzed, including both legislation and enforcement practice. This article analyzes such enforcement problems as: classification problems (tacit vs explicit collusion, vertical vs horizontal agreements), flexibility of prohibitions (“per se” vs “rule of reason”), design of sanctions, private enforcement challenge, leniency program mechanisms, the role of antitrust authorities etc. Main challenges for policy effectiveness in this field were shown

Added: Dec 4, 2014

Working paper

Despite of the fact that the history of Initial Coin Offering (ICO) is short, new modification of it has already suggested. According to the ICORating , in the second half of 2018, the profitability of investments in blockchain startups decreased by 22%, and 58% of ICO projects announced in Q4 2018 were not able to raise more than 100,000 USD. Moreover, in Q4 2018 40% of projects with previously announced ICOs have already deleted their social network accounts and websites. The founder of Ethereum Vitalik Buterin (2015), who started the first ICO, proposed a new way of decentralized fundraising called DAICO in 2018. This new model will include elements of Decentralized Autonomous Organizations (DAO), and its purpose will be to minimize the difficulties and risks associated with the ICO. At the same time, in 2018 another model of financing appeared called Initial Exchange Offering (IEO) in order to minimize risks, problems of liquidity and the postponement of the listing of the tokens at the end of tokensale step. More than 70 IEOs listed on ICObench with average rating of 3.6 and 42 IEOs have been ended and raised $266 million in total. Nevertheless, there three types of tokens 95% of ICO projects are utility-based token. This makes ICO comparable to crowfunding. In order to be more attractive for investors the focus on a new wave of ICO projects is on the security type of tokens. The security token is any cryptocurrency that pays dividends, profits, shares or interest or invests in any other asset that also generates profits. The U.S. Securities and Exchange Commission (SEC) use the Howey Test and concludes the securities token are securities in contract to classical utility token of ICO projects. In order to back by real assets and follow the SEC's guidance on compliance, issuance, and trading new model is called Security Token Offering (STO) and differs from ICO. All three new models are a new focus for small and medium-sized enterprises (SME) and investors. The absence of any type of academic works emphasizes the relevance and scientific novelty of the forthcoming research. The contribution to the existing literature is the systematization of information and comparison analyses of ICO, DAOICO, IEO and STO by method of case study.

Added: Sep 4, 2019