Optimal Consumption Choice under Uncertainty with Intertemporal Substitution

This abstract will be reformatted upon submission. You don't need to format for line-breaks here!!!!! We extend the analysis of the intertemporal utility maximization problem for Hindy-Huang-Kreps utilities reported in Bank/Riedel(1999) to the stochastic case. Existence and uniqueness of optimal consumption plans are established under arbitrary convex portfolio constraints, including the cases of both complete and incomplete markets. For the complete market setting, Kuhn-Tucker-like necessary and sufficient conditions for optimality are given. Using this characterization, we show that optimal consumption plans are obtained by reflecting the associated level of satisfaction on a stochastic lower bound. When uncertainty is generated by a L{\'e}vy process and agents exhibit constant relative risk aversion, closed-form solutions are derived. Depending on the structure of the underlying stochastics, optimal consumption occurs at rates, in gulps, or singular to Lebesgue measure.Hindy-Huang-Kreps preferences, non-time additive utility optimization, intertemporal utility, intertemporal substitution

International stock portfolio selection and performance measure recognizing higher moments of return distributions

Since the seminal works of Markowitz (1952), Sharpe (1964), and Lintner (1965), numerous studies on portfolio selection and performance measure have been based upon the mean-variance framework. However, several researchers [e.g., Arditti (1967, and 1971), Samuelson (1970), and Rubinstein (1973)] argue that the higher moments cannot be neglected unless there is reason to believe that: (i) the asset returns are normally distributed and the investor\u27s utility function is quadratic, or (ii) the empirical evidence demonstrates that higher moments are irrelevant to the investor\u27s decision. Based on the same argument, this dissertation investigates the impact of higher moments of return distributions on three issues concerning the 14 international stock markets. First, the portfolio selection with skewness is determined using the Polynomial Goal Programming in which investor preferences for skewness can be incorporated. The empirical findings suggest that the return distributions of international stock markets are not normally distributed, and that the incorporation of skewness into an investor\u27s portfolio decision causes a major change in the construction of his optimal portfolio. The evidence also indicates that an investor will trade expected return of the portfolio for skewness. Moreover, when short sales are allowed, investors are better off as they attain higher expected return and skewness simultaneously. Second, the performance of international stock markets are evaluated using two types of performance measures: (i) the two-moment performance measures of Sharpe (1966), and Treynor (1965), and (ii) the higher-moment performance measures of Prakash and Bear (1986), and Stephens and Proffitt (1991). The empirical evidence indicates that higher moments of return distributions are significant and relevant to the investor\u27s decision. Thus, the higher moment performance measures should be more appropriate to evaluate the performances of international stock markets. The evidence also indicates that various measures provide a vastly different performance ranking of the markets, albeit in the same direction. Finally, the inter-temporal stability of the international stock markets is investigated using the Parhizgari and Prakash (1989) algorithm for the Sen and Puri (1968) test which accounts for non-normality of return distributions. The empirical finding indicates that there is strong evidence to support the stability in international stock market movements. However, when the Anderson test which assumes normality of return distributions is employed, the stability in the correlation structure is rejected. This suggests that the non-normality of the return distribution is an important factor that cannot be ignored in the investigation of inter-temporal stability of international stock markets

Why do we invest ethically?

Analysis in this paper has proposed three potential motives for ethical investment - financial returns, non-wealth returns and social change. The motives are developed from the literature and illustrated in the context of a 'best of sector' fund and a socially screened fund. We find that the proposed motives are neither exhaustive nor exclusive and one single motive will not explain the behaviour of all ethical investors. There may be a trade-off between financial and psychic returns for some investors. The trade-off for consumption-investors is expected to be close to zero (total utility is maximised with small levels of ethical investment in the fun of participation model) and is expected to vary with the ethical intensity of investment-investors, as shown when we include ethical intensity into the investor's utility function. Psychic return can also be viewed as an increase in happiness and this approach would lend itself to empirical testing to increase our understanding of why we invest ethically

Fuzziness and Funds Allocation in Portfolio Optimization

Each individual investor is different, with different financial goals, different levels of risk tolerance and different personal preferences. From the point of view of investment management, these characteristics are often defined as objectives and constraints. Objectives can be the type of return being sought, while constraints include factors such as time horizon, how liquid the investor is, any personal tax situation and how risk is handled. It's really a balancing act between risk and return with each investor having unique requirements, as well as a unique financial outlook - essentially a constrained utility maximization objective. To analyze how well a customer fits into a particular investor class, one investment house has even designed a structured questionnaire with about two-dozen questions that each has to be answered with values from 1 to 5. The questions range from personal background (age, marital state, number of children, job type, education type, etc.) to what the customer expects from an investment (capital protection, tax shelter, liquid assets, etc.). A fuzzy logic system has been designed for the evaluation of the answers to the above questions. We have investigated the notion of fuzziness with respect to funds allocation.Comment: 21 page

On optimal investiment strategies

Suppose an investor has a fixed decision horizon and an appropriate utility function for measuring his or her utility of wealth. If there are only two investment vehicles, a risky and a risk-free asset, then the optimal investment strategy is such that, at any time, the amount invested in the risky asset must be the product of his or her "current risk tolerance” and the risk premium on the risky asset, divided by the square of the diffusion coefficient of the risky asset. In the case of more than one risky asset, the optimal investment strategy is similar, with the ratios of the amounts invested in the different risky assets being constant over tim

Serial Correlation of Asset Returns and Optimal Portfolios for the Long and Short Term

Optimal portfolios differ according to the length of time they are held without being rebalanced. For the case in which asset returns are identically and independently distributed, it has been shown that optimal portfolios become less diversified as the holding period lengthens.We show that the anti-diversification result does not obtain when asset returns are serially correlated, and examine properties of asymptotic portfolios for the case where the short term interest rate, although known at each moment of time, may change unpredictably over time. The theoretical results provide no presumption about the effects of the length of the holding period on the optimal portfolio. Using estimated processes for stock and bill returns, we show that calculated optimal portfolios are virtually invariant to the length of the holding period. The estimated processes for asset returns also imply very little difference between portfolios calculated ignoring changes in the investment opportunity set and those obtained when the investment opportunity set changes over time.

The quality of bureaucracy and capital account policies

The extent of bureaucracy varies extensively across countries, but the quality of bureaucracy within a country changes more slowly than economic policies. The authors propose that the quality of bureaucracy may be an important structural determinant of open economy macroeconomic policies - especially the imposition or removal of capital control. In their model, capital controls are an instrument of financial repression. They entail efficiency loss for the economy but also generate implicit revenue for the government. The results show that bureaucratic corruption translates into the government's reduced ability to collect tax revenues. Even if capital controls and financial repression are otherwise inefficient, the government still has to rely on them to raise revenues to provide public goods. Among the countries for which the authors could get relevant data, they find that the more corrupt ones are indeed more likely to impose capital controls, a pattern consistent with the model's prediction. To deal with possible reverse causality, they use the extent of corruption in a country's judicial system, and the degree of democracy, as the instrumental variables for bureaucratic corruption. The instrumental variable regressions show the same result: more corrupt countries are associated with more severe capital controls. The results suggest that as countries develop and improve their public institutions, reducing bureaucratic corruption over time, they will choose to gradually liberalize their capital accounts. Removing capital controls prematurely when forced by outside institutions to do so could reduce rather than improve their economic efficiency.Banks&Banking Reform,Governance Indicators,Environmental Economics&Policies,Economic Theory&Research,National Governance

Designing personalized intelligent decision support systems: the impact of risk attitude on using secury selection models

The variety of investment methods and the complexity of investment decisions have increased steadily in the last two decades. This growth has created a need for comprehensive and expandable financial decision support systems that embody major approaches toward investment decisions. The question is whether such systems should take into account the investor's unique requirements and personal characteristics. This paper reports on the first phase of our research. Here, we design such a system, create a prototype, and use it for an exploratory investigation of the impact of investors' individual characteristics on their use of models in making decisions. More specifically, we report on how investors' attitudes towards risk, gender, and age relatetheir choice of investment models.info:eu-repo/semantics/publishedVersio