On the real effects of private equity investment: evidence from new business creation

Using a comprehensive database of European firms, we study how private equity affects the rate of firm entry. We find that private equity investment benefits new business incorporation, especially in industries with naturally higher entry rates and R&D intensity. A two standard deviation increase in private equity investment explains as much as 5.5% of the variation in entry between high-entry and low-entry industries. We address endogeneity by exploiting data on laws that regulate private equity investments by pension funds. Our results hold when we correct for barriers to entry, general access to credit, protection of intellectual property, and labor regulations. JEL Classification: G24, L26, M13firm entry, private equity, Venture Capital

Does private equity investment spur innovation? Evidence from Europe

We provide the first cross-country evidence of the effect of investment by private equity firms on innovation, focusing on a sample of European countries and using Kortum and Lerner’s (2000) empirical methodology. Using an 18-country panel covering the period 1991-2004, we study how private equity finance affects patent applications and patent grants. We address concerns about causality in several ways, including exploiting variation in laws regulating the investment behaviour of pension funds and insurance companies across countries and over time. We also control for the standard determinants of innovation like R&D, human capital, and patent protection. Our estimates imply that while private equity investment accounts for 8% of aggregate (private equity plus R&D) industrial spending, PE accounts for as much as 12% of industrial innovation. We also present similar evidence from the biotech industry to alleviate concerns that our results are biased by aggregation. JEL Classification: C23, G15, O16innovation, private equity, Venture Capital

On polarizations in invariant theory

Given a reductive algebraic group $G$ and a finite dimensional algebraic $G$-module $V$, we study how close is the algebra of $G$-invariant polynomials on $V^{\oplus n}$ to the subalgebra generated by polarizations of $G$-invariant polynomials on $V$. We address this problem in a more general setting of $G$-actions on arbitrary affine varieties.Comment: 15 page

A Survey on Experimental Performance Evaluation of Data Distribution Service (DDS) Implementations

The Data Distribution Service (DDS) is a widely used communication specification for real-time mission-critical systems that follow the principles of publish-subscribe middleware. DDS has an extensive set of quality of service (QoS) parameters allowing a thorough customisation of the intended communication. An extensive survey of the performance of the implementations of this communication middleware is lacking. This paper closes the gap by surveying the state of the art in performance of various DDS implementations and identifying any research gaps that exist within this domain.Comment: 20 pages and 1 figur

Exploring the Effects of Multicast Communication on DDS Performance

The Data Distribution Service (DDS) is an Object Management Group (OMG) standard for high-performance and real-time systems. DDS is a data-centric middleware based on the publish-subscribe communication pattern and is used in many mission-critical, or even safety-critical, systems such as air traffic control and robot operating system (ROS2). This research aims at identifying how the usage of multicast affects the performance of DDS communication for varying numbers of participants (publishers and subscribers). The results show that DDS configured for multicast communication can exhibit worse performance under a high load (a greater number of participants) than DDS configured for unicast communication. This counter-intuitive result reinforces the need for researchers and practitioners to be clear about the details of how multicast communication operates on the network.Comment: 4 pages, 2 tables, 3 figures, and presented at EDCC 2022 (European Dependable Computing Conference). Editor: Ib\'eria Medeiros. 18th European Dependable Computing Conference (EDCC 2022), September 12-15, 2022, Zaragoza, Spain. Student Forum Proceedings - EDCC 202

FOREWORD TO THE THEMATIC ISSUE: WEAR PARTICLE TRANSPORT AND EMISSION: MECHANISMS AND ENVIRONMENTAL IMPLICATIONS

The papers of the present Special Issue as well as a number of papers of the subsequent Issues of Facta Universitatis – Series Mechanical Engineering represent extended versions of the research works presented at the International Workshop "Wear particle transport and emission: Mechanisms and environmental implications" which was carried out online from 24. to 25. February 2021

Nonnegative matrix semigroups with finite diagonals

AbstractLet S be a multiplicative semigroup of matrices with nonnegative entries. Assume that the diagonal entries of the members of S form a finite set. This paper is concerned with the following question: Under what circumstances can we deduce that S itself is finite

Modeling software design diversity

Design diversity has been used for many years now as a means of achieving a degree of fault tolerance in software-based systems. Whilst there is clear evidence that the approach can be expected to deliver some increase in reliability compared with a single version, there is not agreement about the extent of this. More importantly, it remains difficult to evaluate exactly how reliable a particular diverse fault-tolerant system is. This difficulty arises because assumptions of independence of failures between different versions have been shown not to be tenable: assessment of the actual level of dependence present is therefore needed, and this is hard. In this tutorial we survey the modelling issues here, with an emphasis upon the impact these have upon the problem of assessing the reliability of fault tolerant systems. The intended audience is one of designers, assessors and project managers with only a basic knowledge of probabilities, as well as reliability experts without detailed knowledge of software, who seek an introduction to the probabilistic issues in decisions about design diversity

A conservative bound for the probability of failure of a 1-out-of-2 protection system with one hardware-only and one software-based protection train

Redundancy and diversity have long been used as means to obtain high reliability in critical systems. While it is easy to show that, say, a 1-out-of-2 diverse system will be more reliable than each of its two individual “trains”, assessing the actual reliability of such systems can be difficult because the trains cannot be assumed to fail independently. If we cannot claim independence of train failures, the computation of system reliability is difficult, because we would need to know the probability of failure on demand (pfd) for every possible demand. These are unlikely to be known in the case of software. Claims for software often concern its marginalpfd, i.e. average across all possible demands. In this paper we consider the case of a 1-out-of-2 safety protection system in which one train contains software (and hardware), and the other train contains only hardware equipment. We show that a useful upper (i.e. conservative) bound can be obtained for the system pfd using only the unconditional pfd for software together with information about the variation of hardware failure probability across demands, which is likely to be known or estimatable. The worst-case result is obtained by “allocating” software failure probability among demand “classes” so as to maximize system pfd