From the Efficient Market Hypothesis to Behavioral Finance: How Investors' Psychology Changes the Vision of Financial Markets

Capital markets provide a function which facilitates the buying and selling of long-term financial securities to increase liquidity and their value, Watson & Head (2013). Hence, the Efficient Market Hypothesis (EMH) explains the relationship that exists with the prices of the capital market securities, where no individual can beat the market by regularly buying securities at a lower price than it should be. This means that in order to be an efficient market prices of securities will have to fairly and fully reflect all available information, Fama (1970). Consequently, Watson & Head (2013) believe that market efficiency refers to the speed and quality of how share price adjusts to new information. Nevertheless, the testing of the efficient markets has led to the recognition of three different forms of efficiency in which explains how information available is used within the market. In this essay, the EMH will be analysed; testing of EMH will show that the model does provide strong evidence to explain share behaviour but also anomalies will be discussed that refutes the EMH. Therefore, a judgment will be made to see which structure explains the efficient market and whether there are some implications with the EMH, as a whole.

As a future business leader, I chose to read the book “The mind of the Market” by Michael Shermer When I first purchased this book I didn't know what to expect, I just knew that I had a series of questions from my macroeconomics, sociology, and history class that would like to explore.

It is believed that Efficient Market Theory is based upon some fallacies and it does not provide strong grounds of whatever that it proposes. More importantly the Efficient Market theory is perceived to be too subjective in its definition and details and because of this it is close to impossible to accommodate this theory into a meaningful and explicit financial model that can actually assist investors in making the investment decisions (Andresso-O’Callaghan, B., 2007).

As Chapter 10 questions, if further evidence continues to surface that capital markets do not always behave in accordance with the efficient market hypothesis, then should we reject the research that has embraced the EMH as a fundamental assumption? In this regard we can return to earlier chapters of this book in which we emphasised that theories are abstractions of reality. Capital markets are made of individuals and as such it would not (or perhaps, should not) be surprising to find that the

According to John Cassidy, markets fail due, not because of greed but rather to the fact that they act irrationally. Their irrational decisions and results can be, in part, hindered and corrected by government intervention.

The Efficient-Market Hypothesis (EMH) states that it is impossible to beat the market because stock market efficiency causes existing share prices to always incorporate and reflect all relevant information.

This document is authorized for use only by Yen Ting Chen in FInancial Markets and Institutions taught by Nawal Ahmed Boston University from September 2014 to December 2014.

Financial theory accepts the belief that a share’s return should be proportional to the risk received by its holder. There is a need of a risk-return equilibrium model. Since the nativity of the efficient market hypothesis (EMH), an equilibrium model was only the Capital Asset Pricing Model (CAPM). The CAPM constitutes of two types of returns, the risk free rate of returns of the Treasury bills and beta times the return on the market portfolio. The following equation is the basis of this model:

The premise of an efficient market is that stock prices adjust accordingly as information is received. The speed and accuracy of the pricing changes are a reflection of the strength of the market efficiency, where in theory a perfectly efficient market will re-adjust prices immediately and precisely with new information. The efficient market hypothesis aligns with beliefs about whether technical and fundamental analyses are useful in making investment decisions or whether a passive approach is appropriate. In a perfectly efficient market, these types of analyses are not able to predict stock price trends (based on market inefficiencies or price abnormalities) which could assist in portfolio positioning or investment management. However, some investors belive that the market pricing is not precise and that there are timing windows and pricing trends that can be identified through analysis of past performance and finding price abnormalities where all information is not correctly reflected in the stock price (Hirt, Block and Basu, 2006).

Under the idea that markets are efficient, stock prices reflect new information quickly and accurately. Furthermore, Morningstar (n.d.) contributes details on the strongest supportive theory of efficient markets, EMH exists in three forms: weak, semi-strong and strong. The hypothesis calls for the existence of informationally efficient markets, were current stock prices reflect all information, and attempts to outperform the market will only come in the form of riskier investments. Also, because of a large number of independent investors actively analyzing new information simultaneously as it enters the market, investors react accordingly and is immediately reflected in the stock

The efficient-market hypothesis (EMH) is one of the well-known methods for measuring the future value of stock prices. According to this hypothesis, the market is efficient if its prices are formed on the basis of all disposable information. According to EMH if there is a possibility to predict the future price of shares, that is the first sign of an inefficient market.

Efficient Market Hypothesis has been controversial issues among researcher for decades. Until now, there is no united conclusion whether capital markets are efficiency or not. In 1960s, Fama (1970) believed that market is very efficient despite there are some trivial contradicted tests. Until recently, both empirical and theatrical efficient market hypothesis was being disputed by behavior finance economist. They have found that investor have psychological biases and found evidences that some stocks outperform other stocks. Moreover, there are evidences prove that market are not efficient for instance financial crisis, stock market bubble, and some investor can earn abnormal return which happening regularly in stock markets all over the world. Therefore, the purpose of this essay is to demonstrate that Efficient Market Hypothesis in stock (capital) markets does not exist in the real world by proofing four outstanding unrealistic conditions that make market efficient: information is widely available and cost-free, investor are rational, independent and unbiased, There is no liquidity problem in stock market, and finally stock prices has no pattern.

The efficient market hypothesis (EMH) has been subject to professional and academic debate and analysis for many years, and refers to the theory proposing that stock prices show all information regarding a firm’s value. An efficient market is a market in which investors with the same information and similar investment goals compete actively (Sewell, 2012). Many private investors and investors aiming to make profits are involved with the stock market and often make low risk investments while aiming for high rates of return. However, the efficient market hypothesis states that it is impossible to consistently outperform the stock market as the market is able to quickly adjust to new information. The Efficient Market Hypothesis also addresses

The efficient market, as one of the pillars of neoclassical finance, asserts that financial markets are efficient on information. The efficient market hypothesis suggests that there is no trading system based on currently available information that could be expected to generate excess risk-adjusted returns consistently as this information is already reflected in current prices. However, EMH has been the most controversial subject of research in the fields of financial economics during the last 40 years. “Behavioural finance, however, is now seriously challenging this premise by arguing that people are clearly not rational” (Ross, (2002)). Behavioral finance uses facts from psychology and other human sciences in order to

Economics is partially mathematical science and partially a study in human psychology. Both financial and psychological factors affect the behavior of investors and the marketplace. For example, one popular theory known as expectations theory is based upon the "hypothesis that long-term interest rates contain a prediction of future short-term interest rates. Expectations theory postulates that you would earn the same amount of interest by investing in a one-year bond today and rolling that investment into a new one-year bond a year later compared to buying a two-year bond today" (Expectations theory, 2012, Investopedia). In other words, a certain consistency is assumed regarding rates, even though many analysts have noted that this simple and elegant theory is often inaccurate and tends to overstate gains (Expectations theory, 2012, Investopedia).