Search results

In this study, we analyze the power of the individual return-to-volatility security performance heuristic (ri/stdi) to simplify the identification of securities to buy and, consequently, to form the optimal no short sales mean–variance portfolios. The heuristic ri/stdi is powerful enough to identify the long and shorts sets. This is due to the positive definiteness of the variance–covariance matrix – the key is to use the heuristic sequentially. At the investor level, the heuristic helps investors to decide what securities to consider first. At the portfolio level, the heuristic may help us find out whether it is a good idea to invest in equity to begin with. Our research may also help to integrate individual security analysis into portfolio optimization through improved security rankings.

We address the problem of selecting a topological design for a network having a single traffic source and uncertain demand at the remaining nodes. Solving the associated fixed charge network flow (FCF) problem requires finding a network design that limits both the fixed costs of establishing links and the variable costs of sending flow to the destinations. In this paper, we discuss how to obtain a sequence of optimal solutions that arise as the demand intensity varies from low levels to high. One of the network design alternatives associated with these solutions will be chosen based upon the dominant selection criteria of the decision maker. We consider both probabilistic and non-probabilistic criteria and compare the network designs associated with each. We show that the entire sequence of optimal solutions can be identified with little more effort than solving a single FCF problem instance. We also provide solution approaches that are relatively efficient and suggest good design alternatives based upon approximations to the optimal sequence.

In this chapter, we propose a nonconventional methodology, the graph theory, which is especially relevant for the study of high-dimensional financial data. We illustrate the advantages of this method in the context of systemic risk in derivative markets, a main subject nowadays in finance. A key issue is that this methodology can be used in various areas. Numerous applications have now to face the challenge of analyzing gigantic financial data sets, which are more and more frequent. We offer a pedagogical introduction to the use of the graph theory in finance and to some tools provided by this method. As we focus on systemic risk, we first examine correlation-based graphs in order to investigate markets integration and inter/cross-market linkages. We then restrain the analysis to a subset of these graphs, the so-called “minimum spanning trees.” We study their topological and dynamic properties and discuss the relevance of these tools as well as the robustness of the empirical results relying on them.

In this chapter different network operations are described in SGL, which may be useful for security applications. Basic network management mechanisms are expressed, capable of working on their own even if traditional communications and internet includings are damaged. These include network creation from scratch, finding paths between nodes, and creating routing tables (RT) allowing for shortest path communications. Also is shown the use of SGT for analysing distributed networks with social flavour by finding strong and weak components in them and changing their topology in crisis situations. Another example is how to outline different communities in a distributed social network, find their topographical centres and evaluate physical distances between them for predicting possible social conflicts, while doing this repeatedly together with simulation of spatial mobility of individuals in time.

In terms of notional value outstanding, derivatives markets declined in both over-the-counter and exchange-traded transactions during the 2007–2009 global financial crisis (GFC) period, as counterparty and credit concerns became pre-eminent. However, during the 2010–2011 second stage of the GFC, markets rebounded and by June 2011 outstandings reached new levels which highlight the importance these contracts continue to play in the day-to-day risk management and trading activities of corporations and financial intermediaries. The bulk of the contracts traded are interest rate-related instruments and are denominated in either US dollars or Euro. Credit-related instruments remain an important market segment, although outstandings remain at pre-crisis period levels. Of particular concern for regulators is the role of non-bank financial intermediaries, which are the main counterparty to derivatives transactions. While their share of the market remains unchanged over the last decade, outstandings overall have increased more than fourfold. The present volume considers the issues that participants face in today's derivatives markets including the potential impact of derivatives on economic stability, pricing issues, modelling as well as model performance and the application of derivatives for risk management and corporate control.

In the Introduction to this Festschrift honoring Norman K. Denzin, the author chronicles Denzin's contributions to the academy over the last 55 years. In so doing, he provides personal reflections on numerous interactions with Denzin, particularly as it relates to mentorship and the forging of community within qualitative inquiry. Also included are brief overviews of all of the articles that comprise the Festschrift.