Inter-Firm Non-Monetary Transactions in Russia: A Literature Review

This paper provides a comprehensive literature review of the use of non- monetary transactions (barter, debt offsets, etc.) in Russia since the fall of Communism. The two primary theories are the credit crunch (liquidity constraint) theory and the virtual economy theory. The former relates to the lack of access to bank credit and cash and the rise of non-monetary transactions as a survival mechanism that oils the gears of the market. The latter asserts that barter is a symptom of a system by which the value added firms (such as Gasprom) subsidize the value destroying firms (the 'white elephants'). Barter allows the two players to arbitrarily set prices so that the value added firm can avoid some of the profit taxes while the value destroying firms can stay alive.barter, non-monetary, Russia, demonetization, transition

Ownership and Firm Performance: Evidence from 25 Countries in Central and Eastern Europe and the Former Soviet Union

Using the joint World Bank and EBRD Business Environment and Enterprise Performance Survey (BEEPS), compiled in 1999, this paper explores the relationship between firm performance and ownership in Central and Eastern Europe (CEE) and the Former Soviet Union (FSU). The literature on privatization and performance has been largely inconclusive, especially now that sample selection bias is taken into account. This paper provides evidence that foreign owned firms perform the best, performing significantly better than state owned enterprises, while firms whose owners are domestic outside companies or individuals also perform better than state owned enterprises but the result is somewhat sensitive to the specification of the model. The more significant, albeit puzzling result, is that insider owned firms perform worse than state owned firms. This result is not significant when looking at manager and worker owned firms separately. In further work, I will explore the determinants of this puzzling result.transition, privatization, ownership, firm performance

Analyzing the Performance of Lock-Free Data Structures: A Conflict-based Model

This paper considers the modeling and the analysis of the performance of lock-free concurrent data structures. Lock-free designs employ an optimistic conflict control mechanism, allowing several processes to access the shared data object at the same time. They guarantee that at least one concurrent operation finishes in a finite number of its own steps regardless of the state of the operations. Our analysis considers such lock-free data structures that can be represented as linear combinations of fixed size retry loops. Our main contribution is a new way of modeling and analyzing a general class of lock-free algorithms, achieving predictions of throughput that are close to what we observe in practice. We emphasize two kinds of conflicts that shape the performance: (i) hardware conflicts, due to concurrent calls to atomic primitives; (ii) logical conflicts, caused by simultaneous operations on the shared data structure. We show how to deal with these hardware and logical conflicts separately, and how to combine them, so as to calculate the throughput of lock-free algorithms. We propose also a common framework that enables a fair comparison between lock-free implementations by covering the whole contention domain, together with a better understanding of the performance impacting factors. This part of our analysis comes with a method for calculating a good back-off strategy to finely tune the performance of a lock-free algorithm. Our experimental results, based on a set of widely used concurrent data structures and on abstract lock-free designs, show that our analysis follows closely the actual code behavior.Comment: Short version to appear in DISC'1

Approximation Algorithms for Energy Minimization in Cloud Service Allocation under Reliability Constraints

We consider allocation problems that arise in the context of service allocation in Clouds. More specifically, we assume on the one part that each computing resource is associated to a capacity constraint, that can be chosen using Dynamic Voltage and Frequency Scaling (DVFS) method, and to a probability of failure. On the other hand, we assume that the service runs as a set of independent instances of identical Virtual Machines. Moreover, there exists a Service Level Agreement (SLA) between the Cloud provider and the client that can be expressed as follows: the client comes with a minimal number of service instances which must be alive at the end of the day, and the Cloud provider offers a list of pairs (price,compensation), this compensation being paid by the Cloud provider if it fails to keep alive the required number of services. On the Cloud provider side, each pair corresponds actually to a guaranteed success probability of fulfilling the constraint on the minimal number of instances. In this context, given a minimal number of instances and a probability of success, the question for the Cloud provider is to find the number of necessary resources, their clock frequency and an allocation of the instances (possibly using replication) onto machines. This solution should satisfy all types of constraints during a given time period while minimizing the energy consumption of used resources. We consider two energy consumption models based on DVFS techniques, where the clock frequency of physical resources can be changed. For each allocation problem and each energy model, we prove deterministic approximation ratios on the consumed energy for algorithms that provide guaranteed probability failures, as well as an efficient heuristic, whose energy ratio is not guaranteed

Massive Splenic Pseudocysts : Report of 2 cases

Splenic cysts can be classified as parasitic and nonparasitic. Non parasitic cysts can be further divided into true and pseudocysts. Pseudocysts of spleen does not contain an epithelial lining. Pseudocysts of spleen are usually post traumatic and they rarely grow to a large size and most of them are asymptomatic. It can be confused with cystic lesions of spleen or pancreas or from the surrounding structures. These cases require exploration and is both diagnostic and therapeutic. Conservative measures to preserve spleen can be considered only in presence of expertise and if remnant functional splenic parenchyma is more than 25 %. Here we present two cases of giant pseudocysts who were confused with malignancy and referred to our centre and were later found to be pseudocysts of spleen. We would like to report these cases as they are rare and as diagnostic dilemmas