Monday, September 2, 2019

An Analysis on Factors influencing on Stock Investment Decision: A Behavioural Finance Perspective

1. Background


Behavioural finance is regarded as an emerging discipline in finance, which is also rapidly expanding. The behavioural finance emerged in the 1980s as a new concept in finance which combines behavioural and psychological aspects of financial decision-making. It challenges the traditional finance to understand why investors behave in a particular manner while investing in financial assets. The standard finance or traditional finance is based on various theories and principle arbitrage principles of Miller & Modigliani; the portfolio principles of Markowitz; the capital asset pricing theory of Sharpe, Lintner & Black; and the option-pricing theory of Black, Scholes & Merton, these theories and principle assumes that market participant behaves rationally so the market is efficient and systematic. The investors are theoretically considered to be rational regarding the investment decision by traditional finance; in other words the mainstream finance believe that the investor assumes that the investment decision is made with rational expectation, furthermore, whenever a new information arrives the investor updates their belief and that is reflected through the investment decision which is to maximize their expected return at a given level of risk.

On the other hand, the behavioural finance incorporates behavioural biases and intellectual psychological component accompanied by economics and finance so that the viable supportive argument can be drawn for the irrational behaviour of people during the financial decision (Javed, Bagh, & Razzaq, 2017). DeBont's and Thaler's (1985) paper on stock market overreaction provides initial ground for behavioural finance. The behavioural finance deals with the human decision process which is subjective to the cognitive illusion which has been discussed by various scholars (e.g. - Illiashenko, 2017; Ritter, 2003).  According to Barberis and Thaler (2003), even though the investors are able to process all the available information accurately, not all the investor are rational, their investment related decision has behavioural preconceptions. Thaler (1994) coined the term 'quasi-rational' which indicate for much less than the full rational situation. In the word of Ritter, (2003) the behavioural finance believes in the asymmetric distribution of financial information. The investor’s decision to invest in a particular stock is an investment decision which is subject to several cognitive illusions, one among these illusions is caused by a heuristic decision process.

Behavioural finance challenges the efficient market perspective and helps to understand why an investor behave in a particular manner while investing in financial assets. The participant of the Stock Market has been relying on the idea that the market is always efficient and investor always tends to show rational investment behaviour. However, the recent studies made in the field of finance and from behavioural finance perspective shows that even though the investors want to maximize their options rationally in their investment decisions, to vary their portfolios and to avoid risk, the investor fails to fulfil those in their investments. According to Kahneman and Tversky (1979), human behaviour doesn’t depend always on a logical base stipulated by conventional financial theories and may move away from rational behaviours in time. In general, behavioural finance studies the psychological aspect of financial decision-making and explains the irrationality of investors in investment decision-making. Usually, the investor’s behaviour deviates from making rational or logical decisions and leans towards being influenced by various behavioural biases

2. Investment Decision Making
The allocation of resources for short, medium or long term with the expected effect to recover the investment with the high return by the help of not only with financial resources but also with material and human resources is regarded as an investment (Virlics, 2013). However, in an economic environment is not certain for the expected return in investment or in other words, the risk exists in the investment can create the uncertainty that the cost of the investment will be recovered and profit will be accomplished. Decision-making, on the other hand, is associated with various aspects of life and is a technical process that involves various steps; it is also believed that decision-making is not made in complete desolation. Decision-making, however, is a cognitive or mental process which results in the selection of the best alternative situation among the available alternative situation. The nature of the decision can be simple or complex, lower impact or higher impact, economic or non-economic, routine or non-routine or so on. In the context of stock investment decision, it is regarded as a decision having an economic, non-routine, complex, and higher financial impact in nature, hence, the decision of the investor to invest is subjective. Various studies suggests that investment decision-making is affected by psychological emotions and behavioural factors so that investment decisions are guided by their desires, goals, prejudice, and emotion. (Kahneman & Tversky, 1979; Evans, 2006; Waweru et al. 2008).  An effort has been made to analyse the behavioural pattern and emotions regarding the investment decision of the investor in behavioural finance perspective.

3. An overview of Behavioural Bias
Financial Investment consists of various kinds of risk and equity share is no exception to this. Each individual has a different level of risk tolerance. The behavioural finances argue on the differences in each individual’s decision-making process with reference to the risk tolerance capacity. Various behavioural factors affecting institutional investors' decision making have been previously tested by several scholars (e.g., Kengatharan & Kengatharan, 2014; Metawa, Hassan, Metawa, & Safa, 2018; Qureshi, Rehman, & Hunjra, 2012; Waweru, Munyoki, & Uliana, 2008; Zahera & Bansal, 2018). Those scholars examined the influence of factors such as Heuristic Variables (HV), Prospect Theory (PT), Herding Effect (HE), Home Bias (HB) etc. on institutional investors' and individual investor’s decision making. On the other hand, variables such as get rich quickly, earn a higher rate of return, and diversify risk to measure have been identified as the factors affecting individual investors’ decision making by the scholars Gill, Biger, Mand, and Gill (2011). Similarly, cash flow, earnings, risk, the degree of safety, and revenue growth are the factors tested by Pasewark and Riley (2010), whereas, higher return and diversification are the factors tested by scholars Gill and Biger (2009).

The previous study by various scholars (e.g., - Kengatharan & Kengatharan, 2014; Kumar & Goyal, 2015; Qureshi, 2012; Virlics, 2013; Waweru et al., 2008; Zahera & Bansal, 2018) studied the relation of investment decision making with equity share and/or institutional investor, etc. Regarding equity share and other financial instruments previous research supports that the investment decision of investor is positively affected by Heuristic Variable (HE), Prospect Theory (PT), Use of Financial Tool (UFT), and Herding Effect (HE) (Kengatharan & Kengatharan, 2014; Qureshi et al., 2012; Waweru et al., 2008), whereas Investor Sentiment (IS) found to mediate the investors’ financial decision in Egyptian Stock market (Metawa et al., 2018). The perception of the investors varies regarding various investment alternatives, such as; the sociological and psychological factors have the dominating influence over economic factor in the investment decision inequity share (Shanmugham 2000; as cited in Nayak, 2013). The investor decides to invest in stock is an investment decision which is subject to several cognitive illusions. The illusions caused by the heuristic decision process and the illusions caused by the adoption of the metal frame is assembled on prospect theory (Waweru et al. 2008). These two categories, as well as Herding and Home Bias, have been presented below.

4. Factors affecting Investment Decision
Following are the major behavioural factors influencing in the investment decision making;

4.1 Heuristic Variable (HV)
            If the complex task of the investment decision-making is done by the rule of thumb by the investor then it is referred to the heuristic. The heuristic decision-making process is useful when there is limited time and the decision maker also have limited accessibility to the resources, this can also reduce the complexities of the problem by assessing the probabilities and predicting values for a simpler judgement (Tversky & Kahneman, 1974). Rule of thumb leads to make decisions based on individual judgement rather than processing any information (Qureshi, 2012) so it may result in the poor decision (Waweru et al., 2008). According to Ritter (2003), Heuristic decision-making is simple to use in an uncertain and complex environment. Tversky and Kahneman (1974) study on HV and introduced three factors namely availability bias, representativeness, and anchoring. Kempf and Ruenzi (2006) also discussed another HV called Gambler’s fallacy, Waweru et al. (2008) discussed one more variable in heuristic called overconfidence.

 Availability Bias
The weight kept by an investor on easily available information helps to emerge availability bias (Barberis & Huang, 2001; Waweru et al., 2008) the investor doesn’t examine the other alternative information and procedures. An investor of the stock market is also influenced by the information they receive, their preferences change according to the available information and sometimes even irrelevant information also influence an investment decision (Javed, Bagh, & Razzaq, 2017). The previous study that investor feels comfortable if they feel that their information in the decision-making process is superior (Weber, 2009).

Representativeness
The representativeness is the following the previous pattern by the investor which may cause serious mistake of arrangement in everyday life (Thaler & Sunstein, 2009). It can manifest when an investor based on past information buys hot stock and avoid poorly performed stock (Kempf & Ruenzi, 2006). Barber and Odean (1999), investigate the impact of representative bias on buying decision and found that the investor buys the attention-grabbing stock which manifested the significant impact of representative bias in their investment decision.

Anchoring
Anchoring refers to the judgement made by the investor on the basis of initial information they receive or “anchor” on one trait or piece of information when making decisions. The anchoring bias was introduced by Tversky and Kahneman in 1981. When an investor is presented with new information, the investors tend to be slow to change or the value scale is fixed or anchored by recent observations (Zaiane, 2015). When a product's’ value is presented earlier to an individual that affects people when they are to estimate an unknown similar product, which then, will be close to the value that was considered before the estimation. An example of the anchoring effect is how you get influenced by the asking price when buying a house (Kahneman, 2011).

Gambler’s fallacy
Gambler’s fallacy occurs when people tend to estimate the likelihood of an event by taking into account how well it represents its parent population, i.e. a sequence of the same outcome (given two possible options) must be followed by the other outcome in order to equilibrate the proportion.  Gambler’s fallacy is referred to “Monte- Carlo fallacy or the Maturity of Chances fallacy” and is studied under behavioural finance. It is the conviction that if divergences/deviations from probable behaviour are experiential in recurring independent tests of some unsystematic procedure then these divergences/deviations are likely to be evened out by contrary deviations in the future. Tversky and Kahneman (1974) interpret gambler’s fallacy to mean that people believe that short sequences of random events should be representative of longer ones, specifically in that deviations from average should balance out. According to Qureshi et al., (2012) Gambler’s fallacy results in poor market return because of improper anticipation. Whereas, the evidence from empirical works that the gambler’s fallacy is also present in the stock market. Andreassen and Kraus (1990) found that investors exhibit gambler’s fallacy in the presence of modest stock price fluctuations.

Overconfidence
De Bondt and Thaler (1985) argued that “the key behavioural factor to understand the trading puzzle is overconfidence.” It is a well-established and common bias that makes people too confident about their knowledge and skills and hence ignore the risk associated with the investment decision (Kumar & Goyal, 2015). The individual generally rates themselves above average to their abilities. Furthermore, with the presence of overconfidence, the individual also underestimates others ability or difficulty of the task. This ‘better than average’ effect has been identified by Svenson (1981). The illusion of control is regarded as another aspect of overconfidence (Langer, 1975) where people generally think that they can hold more control over the events than they actually have. An overconfident investor emphasizes that the individual hold and under-emphasizes the public resources that can be available either free of cost or with some cost from the economic environment. So, the overconfident investor, despite correcting their private information by publicly available information, they believe heavily in private information which they own. The overestimation of the probability of a good event happening to the investor may create an entire problem, the financial instability is underestimated. Overconfidence in stock investment decision also arises with the past experience of the investor. An experimental study of Dittrich, Guth, and Maciejovsky (2005) on overconfidence in investment decisions result that in the event of sub-optimal choices and complex decision the overconfidence is positively associated whereas it is negatively associated with age and decision uncertainties.

4.2 Prospect Theory (PT)
The behavioural ability for the risk tolerance of the investor in investment decision making is described by Prospect theory. The two approaches for decision making are Expected Utility Theory (EUT) and Prospect Theory are mentioned by various scholars (e.g. - Kengatharan & Kengatharan, 2014; Waweru et al., 2008). The prospect theory is heavily influenced by investor's value system has and it has the major focus on subjective decision making whereas the EUT focuses on the rational expectations of the investors (Filbeck et al. 2008, as cited in Waweru et al., 2008). The investor tries to avoid the risk is risk aversion; this kind of behaviour of the investor was discussed in the earlier days by Gupta & Govindarajan (1984).
            "Investors are risk averse and they make the investment decision for maximizing their wealth and claim to be rational but contrary to this investor show various risk tendency” (Neumann & Morgenstern, 1947, as cited in Qureshi et al., 2012, p. 282).
 The primary view on risk in finance and economics is through the expected utility approach (Neumann and Morgenstern, 1947, as cited in Mayfield, Perdue, & Wooten, 2008). According to Keller & Siegrist (2006), the affinity for money matters varies from risk seeker investor to risk avoider investor, these risk seeker investors' attitude towards the financial risk is positive and is willing to accept investment risk. Regret aversion, Loss aversion, and Mental accounting are some of the situation of mind which affect investors decision-making process (Waweru et al., 2008).

Regret Aversion
The emotional reaction of the people after they make a mistake is regret. It was invented in three different paper. (Looms & Sugden, 1982; Bell 1982; Fishburn 2013, as cited by Zahera & Bansal, 2018). The regret of a particular decision has a significant impact on the future decision that could be made by the individual. This can be two-directional, first, they can be motivated to take more risk and second they avoid to take the risk. This is generally done to avoid any feeling of regret in the future.

Loss Aversion
Loss Aversion is based on the observation that people feel much more pain for their loss than the pleasure from an equivalent gain (Kahneman & Tversky, 1979). Various scholars indicate the mental penalty of the individual at a different level is more for the loss of then for the reward of similar size (e.g. - Barberis & Huang, 2001; Shiller, 2000 as cited in Waweru et al., 2008). The loss aversion configures the decision makers’ tendency of being more sensitive in the loss they can make then the same amount of gain that they can make from an investment. The choice of risk behaviour is thus made either by the maximisation of the utility expectation or by the feeling of loss aversion (Vigna & Licalzi, 1999).

Mental Accounting
Mental accounting was initially proposed by Thaler (1985) and implies that the investor divides their investment in the various portfolio on the basis of the number of categories that they hold. In the words Barberis and Huang (2001), Mental accounting is the process which allows the individual to consider and examine their financial activities. It is the situation where individual start to organize their world into separate metal account, the investor separates their portfolio into a separate account (Ritter, 2003). The investor uses separate investment policies for each mental account so that the specific purpose of the investment such as; maximisation of profit, minimisation of risk could be attended by the investor. This could eventually result in the selection of those portfolios that are not profitable yet they satisfy the emotions of the investor (Zahera & Bansal, 2018).

3.3 Herding Effect (HE)
Herding indicates the situation when a rational investor starts behaving irrationally by imitating others judgement for making a decision or in other words of  Kengatharan and Kengatharan (2014) the tendency of the investors' behaviour to follow other behaviour is without having individual judgement is described as herding effect in the financial market. The impact on stock price change influence the investment decision of the investor followed by the changes on risk/return models and this can have the impact on the perspective of theories of assets pricing (Tan, Chiang, Mason & Nelling, 2008, as cited in Kengatharan & Kengatharan, 2014).  In the words of Waweru et al. (2008), HE can drive stock trading to create new momentum in the financial market. Furthermore, Waweru et al. (2008) also argued that the decisions such as; buying, selling, choice of stock, length of time to hold stock, and volume of stock to trade are the investor's decision that an investor can be impacted by other. Shiller and Pound (1986) empirical study on herding behaviour on the stock market shows that the influence of information by professionals on investment of major institutional investor in the stock market. Furthermore, regarding the consequences of the neglecting the intrinsic value of the stock by the investor the market tends to be an inefficient market. Benerjee (1992), illustrates an empirical model for the asymmetric information in an inefficient market showing herding behaviour.

4.4 Home Bias
Home Bias was first introduced by French and Poterba (1991) which refers to the situation where the individual of the institution prefers to hold on domestic securities rather than foreign securities in their portfolio (Kumar & Goyal, 2015). The feeling of belongingness of the investor towards their domestic companies over foreign companies, even though the domestic company has a lower return than the foreign company is home bias (Zahera & Bansal, 2018). The possible reasons behind home bias may be investment barriers, transaction costs, information asymmetry, inflation hedging, and non-tradable assets. Various research studies have elucidated that there are no conclusive explanations for home bias, so it remains a puzzle among market participants. Coval and Moskowitz (1999), Lewis (1999), Tesar and Werner (1995) have also contributed by giving insightful meaning in the area of home bias.

4.5 Other kinds of Bias
The other kind of bias that has not been mentioned above are;
Disposition Effect: This is a behavioural bias that occurs whenever an investor is prone to sell winning stock and tend to hold loss-making stock.
Confirmation Bias: When people generally, have a pre-convinced impression about something or some information, they rely heavily on this information and confirmation bias occurs.
Framing: When information is provided in the positive frame then investor seeks to profit on the trading based on this information and if the same information is provided in the negative frame then they are ready to take the risk to avoid loss.
Hindsight Bias: It occurs when an investor believes that happening of some event can be predicted through another event. An investor can be sometimes irrational by connecting the uncorrelated events.
Self-attribution Bias: People attribute their success to their hard work, intelligence and so on whereas they blame their failure to others or some outside factor.
Conservatism Bias: It occurs when an investor does not accept outside information and stick on their own belief.
Familiarity Bias: It is the shortcut that mind uses to filter information and make decisions which consist of the tendency to believe in and prefer things that are already familiar to us.
Regency: If the investment decision is based on recent information, such as news, and avoid past information which is helpful in decision making then such bias is called Regency.

6. Conclusion
The field of behavioural finance has grown considerably in the past few decades. The traditional finance theorists and behavioural finance economists are constantly at head-to-head with each other. The traditional theorist argues that the behavioural financial theories are incomplete and doesn’t lead to a destination of objective decision whereas the behavioural theorist argues that it is extremely important to understand that biases in behaviour and psychological differences play a key role in the investment decision-making process. It gives several possible reasons as to why anomalies occur in an efficient market and why stock prices divert from their fundamental values, however, it doesn’t negate the efficient market hypothesis completely. Also, many important literature studies have been done in behavioural finance except including some landmark studies by (Kahneman & Tversky, 1979) in developing the Prospect Theory.
As a fundamental part of human nature, behavioural biases affect all types of investors, both institutional and individual. The heuristic decision making, which consists of anchoring, overconfidence, availability bias, gamblers fallacy, and representativeness occurs during the investment decision-making and these factors influence the decision-making of the investor without having prior knowledge in it. The prospect theory, herding effect and home bias are the other behavioural variables that seem to influences on the investment decision making. Various studies have shown that these variables, however, doesn't occur simultaneously. So, if the investor understand them and their effects, they may be able to reduce their influence and learn to work around them.


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