17,395 research outputs found
Estimated Correlation Matrices and Portfolio Optimization
Financial correlations play a central role in financial theory and also in
many practical applications. From theoretical point of view, the key interest
is in a proper description of the structure and dynamics of correlations. From
practical point of view, the emphasis is on the ability of the developed models
to provide the adequate input for the numerous portfolio and risk management
procedures used in the financial industry. This is crucial, since it has been
long argued that correlation matrices determined from financial series contain
a relatively large amount of noise and, in addition, most of the portfolio and
risk management techniques used in practice can be quite sensitive to the
inputs. In this paper we introduce a model (simulation)-based approach which
can be used for a systematic investigation of the effect of the different
sources of noise in financial correlations in the portfolio and risk management
context. To illustrate the usefulness of this framework, we develop several toy
models for the structure of correlations and, by considering the finiteness of
the time series as the only source of noise, we compare the performance of
several correlation matrix estimators introduced in the academic literature and
which have since gained also a wide practical use. Based on this experience, we
believe that our simulation-based approach can also be useful for the
systematic investigation of several other problems of much interest in finance
Risk reduction and diversification in UK commercial property portfolios
The issue of diversification in direct real estate investment portfolios has been one of the most widely studied topics in academic and practitioner literature. Most work, however, has been done using mean returns and risks for broad market segments as inputs to asset allocation models, or in a few cases using data from small sets of individual properties. This paper reports results from a comprehensive testing of asset allocation modelling drawing on records of 10,000+ UK properties tracked by Investment Property Databank. It provides for the first time robust estimates of the diversification gains attainable given return, risk and cross-correlations across individual properties actually available to fund managers. The discussion of results covers implications for the number of assets and amount of money needed to construct âbalancedâ portfolios by direct investment, or via indirect specialist vehicles.Publisher PD
Identifying, measuring and management risks in Russian secondary stock markets
: This paper outlines the changes and challenges of Emerging Russian Stock Market and investment strategy of portfolio management for the period 1996-1998 . It also taste the West models of optimization of portfolio risks and investment decisions for Russia. The major purpose of this article was to enhance the understanding of the participants in securities markets and enhance the performance of its stock and Emerging securities. This article will review the trends in the markets and help focus on the corporate risks and management and a detailed and developed conception of the mechanism of the initial public offerings and public placement of securities the global stock markets such as the U.S., Western Europe and emerging markets. It also outlined the regulatory structure and investor?s risk management tools required by western investors. In light of the recent ?financial crisis? in Russia and other major markets such as Asia, these tools will be increasing important. During much of the past decade the Russian Securities market has been developing into a number of areas including federal securities (GKO-OFZ), sub-federal (oblast) and municipal issues, corporate securities, Ag Bonds, futures, forward contracts and currency instruments. This article is developing in all those areasm .These will be increasing important in light of the new banking environment and securities laws and regulations. In 1997 Russia has joined the league of the few emerging markets that have market capitalizations of over 104 Billion and has a YTD of 134 %. The recent ?Asian induced? corrections in the markets have reduced this by 20-40% according to private estimates. Nevertheless, it remains one of the most vibrant emerging securities markets in the world. The training focused on a number of issues related to emerging market securities including privatization, auctions, IPO?s and new products in the securities markets.
RISK COSTS AND THE CHOICE OF MARKET RETURN INDEX
Six measures of returns are used to estimate the most "Ăâappropriate"Ăâ market index for southeast Kansas farms. Results suggest that localized indices are more appropriate than state indices for use as the market index. The appropriate index was used to estimate systematic and nonsystematic risk and risk costs for farm planning. Estimated risks depend on the choice of market index, whereas risk costs depend on the index choice and the risk aversion are considered. More risk-averse specialized farmers are not completely compensated for risk.Farm Management, Risk and Uncertainty,
Risk and Return: Consumption versus Market Beta
The interaction between the macroeconomy and asset markets is central to a variety of modern theories of the business cycle. Much recentwork emphasizes the joint nature of the consumption decision and the portfolio allocation decision. In this paper, we compare two formulations of the Capital Asset Pricing Model. The traditional CAPM suggests that the appropriate measure of an asset's risk is the covariance of the asset's return with the market return. The consumption CAPM, on the other hand, implies that a better measure of risk is the covariance with aggregate consumption growth. We examine a cross section of 464 stocks and find that the beta measured with respect to a stock market index outperforms the beta measured with respect to consumption growth.
A two-Factor Asset Pricing Model and the Fat Tail Distribution of Firm Sizes
In the standard equilibrium and/or arbitrage pricing framework, the value of
any asset is uniquely specified from the belief that only the systematic risks
need to be remunerated by the market. Here, we show that, even for arbitrary
large economies when the distribution of the capitalization of firms is
sufficiently heavy-tailed as is the case of real economies, there may exist a
new source of significant systematic risk, which has been totally neglected up
to now but must be priced by the market. This new source of risk can readily
explain several asset pricing anomalies on the sole basis of the
internal-consistency of the market model. For this, we derive a theoretical
two-factor model for asset pricing which has empirically a similar explanatory
power as the Fama-French three-factor model. In addition to the usual market
risk, our model accounts for a diversification risk, proxied by the
equally-weighted portfolio, and which results from an ``internal consistency
factor'' appearing for arbitrary large economies, as a consequence of the
concentration of the market portfolio when the distribution of the
capitalization of firms is sufficiently heavy-tailed as in real economies. Our
model rationalizes the superior performance of the Fama and French three-factor
model in explaining the cross section of stock returns: the size factor
constitutes an alternative proxy of the diversification factor while the
book-to-market effect is related to the increasing sensitivity of value stocks
to this factor.Comment: 38 pages including 7 tables and 3 figure
Time-Varying Beta Estimators in the Mexican Emerging Market
This paper compares the performance of three different time-varying betas that have never previously been compared: the rolling OLS estimator, a nonparametric estimator and an estimator based on GARCH models. The study is conducted using returns from the Mexican stock market grouped into six portfolios for the period 2003-2009. The comparison, based on asset pricing perspective and mean-variance space returns, concludes that GARCH based beta estimators outperform the others when the comparison is in terms of time series while the nonparametric estimator is more appropriate in the cross-sectional context.time-varying beta, nonparametric estimator, GARCH based beta estimator
Risk Sharing and Asset Prices: Evidence From a Natural Experiment
When countries liberalize their stock markets, firms that become eligible for purchase by foreigners (investible), experience an average stock price revaluation of 10.4 percent. Since the covariance of the median investible firm's stock return with the local market is 30 times larger than its covariance with the world market, liberalization reduces the systematic risk associated with holding investible securities. Consistent with this fact: 1) the average effect of the reduction in systematic risk is 3.4 percentage points, or roughly one third of the total effect; and 2) variation in the firm-specific response is directly proportional to the firm-specific change in systematic risk. The statistical significance of this proportionality persists after controlling for changes in expected future profits and index inclusion criteria such as size and liquidity.
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