Dynamic portfolio optimization with inverse covariance clustering

Market conditions change continuously. However, in portfolio investment strategies, it is hard to account for this intrinsic non-stationarity. In this paper, we propose to address this issue by using the Inverse Covariance Clustering (ICC) method to identify inherent market states and then integrate such states into a dynamic portfolio optimization process. Extensive experiments across three different markets, NASDAQ, FTSE and HS300, over a period of ten years, demonstrate the advantages of our proposed algorithm, termed Inverse Covariance Clustering-Portfolio Optimization (ICC-PO). The core of the ICC-PO methodology concerns the identification and clustering of market states from the analytics of past data and the forecasting of the future market state. It is therefore agnostic to the specific portfolio optimization method of choice. By applying the same portfolio optimization technique on a ICC temporal cluster, instead of the whole train period, we show that one can generate portfolios with substantially higher Sharpe Ratios, which are statistically more robust and resilient with great reductions in the maximum loss in extreme situations. This is shown to be consistent across markets, periods, optimization methods and selection of portfolio assets

Distance measures for Portfolio Selection

The classical Markowitz approach to the portfolio selection problem (PSP) consists of selecting the portfolio that minimises the return variance for a given level of expected return. By solving the problem for different values of this expected return we obtain the Pareto efficient frontier, which is composed of non-dominated portfolios. The final user has to discriminate amongst these points by resorting to an external criterion in order to decide which portfolio to invest in. We propose to define an external portfolio that corresponds to a desired criterion, and to assess its distance from the Markowitz frontier in market allowing for short-sellings or not. We show that this distance is able to give us useful information about out-of-sample performances. The pursued objective is to provide an operational method for discriminating amongst non-dominated portfolios considering the investors\u2019 preference

UA45/1/2 Bulletin, Vol. 59, No. 1

Graduate course catalog and informational booklet regarding Western Kentucky University

Geometrical Methods in Multivariate Risk Management: Algorithms and Applications

This thesis builds a framework for evaluating downside risk from multivariate data via a special class of risk measures (RM). The peculiarity of the analysis lies in getting rid of strong data distributional assumptions and in orientation towards the most critical data in risk management: those with asymmetries and heavy tails. At the same time, under typical assumptions, such as the ellipticity of the data probability distribution, the conformity with classical methods is shown. The constructed class of RM is a multivariate generalization of the coherent distortion RM, which possess valuable properties for a risk manager. The design of the framework is twofold. The first part contains new computational geometry methods for the high-dimensional data. The developed algorithms demonstrate computability of geometrical concepts used for constructing the RM. These concepts bring visuality and simplify interpretation of the RM. The second part develops models for applying the framework to actual problems. The spectrum of applications varies from robust portfolio selection up to broader spheres, such as stochastic conic optimization with risk constraints or supervised machine learning

The Impact of CEO Home Bias on CSR, Earnings Management, and M&As

This thesis investigates the effects of CEO home bias on corporate actions through three individual but interweaved essays. Specifically, the first essay studies whether social trust sourced from CEOs’ birthplaces affects corporate social responsibility decisions. Using a sample of US public firms, this essay finds that CEOs who manage firms headquartered in their birth states engage in more corporate social responsibility (CSR) activities. The results suggest that the idiosyncratic styles of managers impact corporate policies in the form of CSR decisions. The second essay examines the effect of CEO home bias on accrual-based earnings management activities. Consistent with the view that home CEOs care more about their reputational capital, this essay finds that home CEOs are associated with significantly less accrual-based earnings management in their firms than non-home CEOs. Overall, the evidence suggests that CEO reputational capital affects earnings management activities within firms. The third essay examines whether CEO home bias affects acquisition deterrence. This essay finds that firms with home CEOs are less likely to receive a takeover bid but more prone to adopt antitakeover provisions. This finding is consistent with the birthplace attachment explanation, which indicates CEOs’ reluctance to lose hometown jobs. This essay also shows that target firms with home CEOs are more likely to withdraw deals during the M&A process but are more willing to complete deals if the acquirer comes from the same state. The findings suggest that having a home CEO on board in the target firm acts as a “shield” against corporate takeovers

How the South African print media cover economics news: a study of inflation news in four newspapers, 1999-2001

There is a considerable amount of literature arguing that economics and business journalism is growing. This subfield of journalism is important as economics issues impact on everyday lives of the people. Media have an important role to inform people about the economy and give them a voice to take part in public debates. The down side though is that economics journalism is criticised for not serving the public well in this aspect. Evidence suggests that economics journalism lost its critical character and that there is closer in economics debates. Using content analysis, this study examines coverage of inflation as reported by South African print media. Three major findings emerged: 1) Evidence shows that there are a variety of cases of inflation. 2) There are also similarities among newspapers on what they view as causing inflation. 3) However, media do not draw sources from all sectors of society. The elite, who are educated people and government officials, are over-accessed while the ordinary citizens - although also affected by inflation – are marginalized. Company and government sources top source lists in the media. It is argued that sources play an important role in shaping the news content. They do so by identifying problems and prescribing potential solutions. They set parameters and define terms of reference. However, media also play a mediating role. They do so by selecting sources and structuring sources in stories. They may chose to quote or report what their sources say and even comment on it. This study concludes that in South Africa ordinary citizens have no voices in economics debates. Media used bureaucratic sources only and that is a consonant agenda on inflation coverage amongst newspapers. The heavy reliance on bureaucratic sources and the exclusion of some sectors of society in sources lists raises questions about impartiality of these sources on issues relating to their organisations and institutions. These are not viable sources that could provide information that could expose abuse of power

Sense-making and storytelling in financial markets: the case of the Istanbul stock exchange

In this thesis, I investigate sense-making processes in financial markets. My focus is on the role of narratives in these routine activities in digital market places or what Cetina and Preda (2007) describe as scopic market systems. I conceptualize narratives told by market professionals in these systems as another form of market device (Callon et al., 2007) which combines different modes of knowing and explanation to cope with flows of data/information and funds, and works to generate value from assets exposed to markets. From a sociological perspective, I argue that the substitution of social network-based information search and face-to-face exchange relationships in financial markets with flow-based and anonymised representations and exchange relationships do not undermine the importance of social networks in shaping sense-making and decision-making in financial markets. However to argue so, I broaden the concept of social network with the help of Bourdieu’s (1997) notion of economic, social and cultural capital. I introduce the notions of field and meta-field of power, habitus, and position-taking by Bourdieu (1997, and Wacquant 1992) to my conceptual discussion of financial markets. In light of this, I describe financial markets as hierarchical and competitive structures inhabited by different groups of investors and intermediaries and shaped by competition and conflict among these groups. I argue that these groups’ position in the field is conditioned by their economic, social, and cultural capital which are generated and sustained within and outwith the field. Consequently, I suggest that these groups’ sense-making and investment activities and their use of market devices including storytelling acts should exhibit distinctive modes in accordance with the specific positions they have voluntarily or involuntarily taken in the field. To substantiate these claims with narrative evidence, I present the case of the Istanbul Stock Exchange (ISE) in Turkey. Opened in 1985, the ISE provides an instrumental case to study the role of sense-making narratives as another form of market device in scopic market systems with a Bourdieusian sociological framework. As gathered from publicly available information and early pilot fieldwork in the ISE headquarters, the ISE as a field has been occupied by three dominant investor types since 1991. These are domestic retail (DRIs), domestic institutional (DIIs), and foreign institutional investors (FIIs). These three groups have a dominant weight in either trading volume or share ownership in the ISE. Drawing on my (participatory) observations between 2008 and 2009 in an asset management company and four brokerage houses which served DRIs and/or DIIs and FIIs, I present evidence on how distinct combinations of economic, social and cultural capitals among these dominant investor-intermediary groups shape their sense-making activities and consequent sense-making stories in the ISE

Graduate Academic Catalog (1989-1990)

This Graduate Catalog is provided by the Graduate Faculty of the University of Nebraska at Omaha in the hope that it will be a source of information to you on the graduate programs available through our University. We are proud of our University and of its programs. We encourage you to become acquainted with us and with the many resources available to the community through the University. The lamp of learning which you see on this page ls the symbol of the scholarship and creative activity which characterizes every graduate program at the University of Nebraska at Omaha. It is this emphasis which distinguishes graduate studies from undergraduate studies. We have tried to include as much information as possible, but obviously we could not include everything. If you have questions which are not answered here, please feel free to call on the Office of Graduate Studies, 204 Eppley Administration Building, Telephone (402) 554-2341

2008-2009-UNM CATALOG

Course catalog for 2008-2009https://digitalrepository.unm.edu/course_catalogs/1098/thumbnail.jp