Samuelson's Dictum and the Stock Market

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.

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

READ: Naked Economics: Undressing the Dismal Science, Charles Wheeland, W.W. Norton, 2003. Completely- cover to cover.

READ: Naked Economics: Undressing the Dismal Science, Charles Wheeland, W.W. Norton, 2003. Completely- cover to cover.

Week 7 Chapter 6: Investors in the Share Market True/False QUESTIONS 1. Investing in shares of publicly listed corporations should, on average, over time provide a higher return than investing in fixed-interest securities. a. True b. False 2. Investments through a stock exchange are limited to ordinary shares issued by listed corporations. a. True b. False 3. Portfolio theory contends that a diversified share portfolio enables an investor to significantly reduce the portfolio’s exposure to systematic risk. a. True b. False 4. A share that has a beta of one is twice as risky as an average share listed on a stock market. a. True b. False 5. Shares that typically demonstrate a negative price correlation will usually move in the same direction

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.

McConnell, C. and Brue, S. (2004). Economics: principles, problems and policies, 16 ed. McGraw-Hill Companies

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).

4) In an efficient market there is no uncertainty because all available information known by everyone, but in in efficient market there is an uncertainty so we don’t know which company makes profit. Which will not be? Increase in business uncertainty activity changes the opinion of investors; it cause to decreased investment in the particular sectors, compared to increased investment in a sector which offers certainty. The increased in uncertainty lead to bubbles take place in the market, if investors decrease to invest in a particular sector which leads to its decrease in bubble. There would be no bubbles created in the efficient 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 weak-form efficiency cannot explain January effect. In semi-strong-form efficient market, to test this hypothesis, researchers look at the adjustment of share prices to public announcements such as earnings and dividend announcements, splits, takeovers and repurchases. As time goes, later tests tend to be not supportive to EMH. For instance, semi-strong-form efficiency cannot explain the pricing/earning effect. In strong-form efficiency, the highest level of market efficiency, Fama (1991) pointed out the immeasurability of market efficiency and suggested that it must be tested jointly with an equilibrium model of expected. However, perfect efficiency is an unrealistic benchmark that is unlikely to hold in practice.

Strong form efficiency is the final form of efficiency. Ross et al. (1993) emphasise all types of information, either public or private, are more likely to be incorporated in the stock market prices when the market is efficiently strong. Additionally, in this kind of market, it is impossible to determine any incomparable investors who are able continually to vanquish the market (Brealey et al., 2011). Expressed differently, strong competition is highly considered among the investors of the strong market efficiency. Therefore, the crucial investors may not be able to keep their high position in the long-term.

A work of Doyle and Chen (2009) stated that stock returns are significantly and consistently lower or higher on some trading days than others. This effect, namely day of the week effect, could enable market participants to benefit from such trading strategies as scheduling the purchase or sale of stocks on the days with historically low or high returns respectively (French, 1980; Kling, 2005; Basher and Sadorsky, 2006). This effect is considered as one of the most remarkable seasonal anomalies, i.e. some securities tend to gain more short-term returns at particular time periods (Lim, Ho and Dollery, 2010). That is reason why the seasonal anomaly cannot be explained by the Efficient market hypothesis, which is defined as

Richard Roll, and University and Auburn, University of Washington, and University of Chicago educated economist, began his career researching the effect of major events of stock prices. This experience likely helped him reach the two conclusions he makes in his 1977 “A Critique Of The Asset Pricing Theory’s Tests”, one of the earliest and most influential arguments against CAPM. In the paper, Roll makes two major claims: that CAPM is actually a redundant equation that just further proves the concept of mean-variance efficiency, and that it is impossible to conclusively prove CAPM. His first claim relates to mean-variance efficiency: the idea that mathematically one must be able to create a portfolio that offers the most return for a given amount of risk. Roll claims that all CAPM is doing is testing a portfolio’s mean variance efficiency, and not actually modeling out projected future returns. The second claim in the paper is that there is not enough data about market returns for CAPM to ever prove conclusive. Even if modern technologies could help alleviate some of the burden of testing market returns for publicly traded equities, there is still no way to account for the returns of less liquid markets, where there is less public information. This means it is impossible for