Portfolio (finance)

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In finance, a portfolio is a collection of investments.

Contents

Definition

Risk/return plot and Pareto-optimal portfolios (in red) Pareto Efficient Frontier for the Markowitz Portfolio selection problem..png
Risk/return plot and Pareto-optimal portfolios (in red)

The term "portfolio" refers to any combination of financial assets such as stocks, bonds and cash. Portfolios may be held by individual investors or managed by financial professionals, hedge funds, banks and other financial institutions. It is a generally accepted principle that a portfolio is designed according to the investor's risk tolerance, time frame and investment objectives. The monetary value of each asset may influence the risk/reward ratio of the portfolio.

When determining asset allocation, the aim is to maximise the expected return and minimise the risk. This is an example of a multi-objective optimization problem: many efficient solutions are available and the preferred solution must be selected by considering a tradeoff between risk and return. In particular, a portfolio A is dominated by another portfolio A' if A' has a greater expected gain and a lesser risk than A. If no portfolio dominates A, A is a Pareto-optimal portfolio. The set of Pareto-optimal returns and risks is called the Pareto efficient frontier for the Markowitz portfolio selection problem. [1] Recently, an alternative approach to portfolio diversification has been suggested in the literatures that combines risk and return in the optimization problem. [2]

Description

There are many types of portfolios including the market portfolio and the zero-investment portfolio. [3] A portfolio's asset allocation may be managed utilizing any of the following investment approaches and principles: dividend weighting, equal weighting, capitalization-weighting, price-weighting, risk parity, the capital asset pricing model, arbitrage pricing theory, the Jensen Index, the Treynor ratio, the Sharpe diagonal (or index) model, the value at risk model, modern portfolio theory and others.

There are several methods for calculating portfolio returns and performance. One traditional method is using quarterly or monthly money-weighted returns; however, the true time-weighted method is a method preferred by many investors in financial markets. [4] There are also several models for measuring the performance attribution of a portfolio's returns when compared to an index or benchmark, partly viewed as investment strategy.

See also

Related Research Articles

Finance refers to monetary resources and to the study and discipline of money, currency, assets and liabilities. As a subject of study, it is related to but distinct from economics, which is the study of the production, distribution, and consumption of goods and services. Based on the scope of financial activities in financial systems, the discipline can be divided into personal, corporate, and public finance.

<span class="mw-page-title-main">Financial economics</span> Academic discipline concerned with the exchange of money

Financial economics is the branch of economics characterized by a "concentration on monetary activities", in which "money of one type or another is likely to appear on both sides of a trade". Its concern is thus the interrelation of financial variables, such as share prices, interest rates and exchange rates, as opposed to those concerning the real economy. It has two main areas of focus: asset pricing and corporate finance; the first being the perspective of providers of capital, i.e. investors, and the second of users of capital. It thus provides the theoretical underpinning for much of finance.

<span class="mw-page-title-main">Capital asset pricing model</span> Model used in finance

In finance, the capital asset pricing model (CAPM) is a model used to determine a theoretically appropriate required rate of return of an asset, to make decisions about adding assets to a well-diversified portfolio.

<span class="mw-page-title-main">William F. Sharpe</span> American economist (born 1934)

William Forsyth Sharpe is an American economist. He is the STANCO 25 Professor of Finance, Emeritus at Stanford University's Graduate School of Business, and the winner of the 1990 Nobel Memorial Prize in Economic Sciences.

Harry Max Markowitz was an American economist who received the 1989 John von Neumann Theory Prize and the 1990 Nobel Memorial Prize in Economic Sciences.

Modern portfolio theory (MPT), or mean-variance analysis, is a mathematical framework for assembling a portfolio of assets such that the expected return is maximized for a given level of risk. It is a formalization and extension of diversification in investing, the idea that owning different kinds of financial assets is less risky than owning only one type. Its key insight is that an asset's risk and return should not be assessed by itself, but by how it contributes to a portfolio's overall risk and return. The variance of return is used as a measure of risk, because it is tractable when assets are combined into portfolios. Often, the historical variance and covariance of returns is used as a proxy for the forward-looking versions of these quantities, but other, more sophisticated methods are available.

Financial risk management is the practice of protecting economic value in a firm by managing exposure to financial risk - principally operational risk, credit risk and market risk, with more specific variants as listed aside. As for risk management more generally, financial risk management requires identifying the sources of risk, measuring these, and crafting plans to mitigate them. See Finance § Risk management for an overview.

Investment management is the professional asset management of various securities, including shareholdings, bonds, and other assets, such as real estate, to meet specified investment goals for the benefit of investors. Investors may be institutions, such as insurance companies, pension funds, corporations, charities, educational establishments, or private investors, either directly via investment contracts/mandates or via collective investment schemes like mutual funds, exchange-traded funds, or Real estate investment trusts.

Financial risk is any of various types of risk associated with financing, including financial transactions that include company loans in risk of default. Often it is understood to include only downside risk, meaning the potential for financial loss and uncertainty about its extent.

The following outline is provided as an overview of and topical guide to finance:

Simply stated, post-modern portfolio theory (PMPT) is an extension of the traditional modern portfolio theory (MPT) of Markowitz and Sharpe. Both theories provide analytical methods for rational investors to use diversification to optimize their investment portfolios. The essential difference between PMPT and MPT is that PMPT emphasizes the return that must be earned on an investment in order to meet future, specified obligations, MPT is concerned only with the absolute return vis-a-vis the risk-free rate.

Performance attribution, or investment performance attribution is a set of techniques that performance analysts use to explain why a portfolio's performance differed from the benchmark. This difference between the portfolio return and the benchmark return is known as the active return. The active return is the component of a portfolio's performance that arises from the fact that the portfolio is actively managed.

A portfolio manager (PM) is a professional responsible for making investment decisions and carrying out investment activities on behalf of vested individuals or institutions. Clients invest their money into the PM's investment policy for future growth, such as a retirement fund, endowment fund, or education fund. PMs work with a team of analysts and researchers and are responsible for establishing an investment strategy, selecting appropriate investments, and allocating each investment properly towards an investment fund or asset management vehicle.

Maslowian portfolio theory (MaPT) creates a normative portfolio theory based on human needs as described by Abraham Maslow. It is in general agreement with behavioral portfolio theory, and is explained in Maslowian Portfolio Theory: An alternative formulation of the Behavioural Portfolio Theory, and was first observed in Behavioural Finance and Decision Making in Financial Markets.

<span class="mw-page-title-main">Portfolio optimization</span> Process of selecting a portfolio

Portfolio optimization is the process of selecting an optimal portfolio, out of a set of considered portfolios, according to some objective. The objective typically maximizes factors such as expected return, and minimizes costs like financial risk, resulting in a multi-objective optimization problem. Factors being considered may range from tangible to intangible.

<span class="mw-page-title-main">Efficient frontier</span> Investment portfolio which occupies the "efficient" parts of the risk-return spectrum

In modern portfolio theory, the efficient frontier is an investment portfolio which occupies the "efficient" parts of the risk–return spectrum. Formally, it is the set of portfolios which satisfy the condition that no other portfolio exists with a higher expected return but with the same standard deviation of return. The efficient frontier was first formulated by Harry Markowitz in 1952; see Markowitz model.

Quantitative analysis is the use of mathematical and statistical methods in finance and investment management. Those working in the field are quantitative analysts (quants). Quants tend to specialize in specific areas which may include derivative structuring or pricing, risk management, investment management and other related finance occupations. The occupation is similar to those in industrial mathematics in other industries. The process usually consists of searching vast databases for patterns, such as correlations among liquid assets or price-movement patterns.

Downside risk is the financial risk associated with losses. That is, it is the risk of the actual return being below the expected return, or the uncertainty about the magnitude of that difference.

Mathematical finance, also known as quantitative finance and financial mathematics, is a field of applied mathematics, concerned with mathematical modeling in the financial field.

In finance, the Markowitz model ─ put forward by Harry Markowitz in 1952 ─ is a portfolio optimization model; it assists in the selection of the most efficient portfolio by analyzing various possible portfolios of the given securities. Here, by choosing securities that do not 'move' exactly together, the HM model shows investors how to reduce their risk. The HM model is also called mean-variance model due to the fact that it is based on expected returns (mean) and the standard deviation (variance) of the various portfolios. It is foundational to Modern portfolio theory.

References

  1. Markowitz, H.M. (March 1952). "Portfolio Selection". The Journal of Finance 7 (1): 77-91
  2. Hatemi-J, A.; El-Khatib, Y. (2015). "Portfolio selection: An alternative approach". Economics Letters . 135 (C): 424–427. doi:10.1016/j.econlet.2015.08.021. Archived from the original on 2016-08-26. Retrieved 2016-08-14.
  3. Momentum Investment Strategies, Portfolio Performance, and Herding: A Study of Mutual Fund Behavior. Mark Grinblatt, Sheridan Titman, Russ Wermers The American Economic Review, Vol. 85, No. 5 (Dec., 1995), pp. 1088-1105
  4. Investment Performance Measurement Errors, accessed 2008-06-29.

Bibliography