Abstract
The present study examines herd behaviour in the Indian equity market using daily prices of 11 broad market indices, 12 sectoral indices, 16 strategic indices and 11 thematic indices from 1 January 2016 to 31 March 2022. For examining herd behaviour, daily returns, overnight returns, intraday spread, absolute market return and squared market return are calculated. Nifty 500 is used as a proxy index for the whole market. The regression models suggested by Christie and Huang (1995) and Chang et al. (2000) are used to calculate Cross-Sectional Standard Deviation (CSSD) and Cross-Sectional Absolute Deviation (CSAD) respectively, which measure the equity return dispersions. It is observed that herding exists in the Indian equity market when we calculate return dispersions using intraday spread. However, no herd presence is found when return dispersions are calculated through daily return, overnight return, absolute market return and squared market return. These results may be useful for investors, policy makers and regulatory bodies. Investors might design their investment strategy while making investment decision. Regulators might be able to formulate their policies to ensure market efficiency in the Indian equity market.
Introduction
The asset pricing model assumes that investors are rational and they tend to behave in such a manner so as to maximize returns. Markets are assumed to be efficient and all information is reflected in the stock prices, thereby making the investors behave rationally (Fama, 1970). However, investors’ sentiments come in between, which oppose the above hypothesis (Shiller, 2003). Investors’ feelings, emotions and psychology play a significant part in the choice to invest. Financial researchers have long been perplexed by investor attitudes regarding stock market trading (Kanojia et al., 2020a). The asset pricing model has been chastised for failing to forecast financial decisions (Kahneman & Tversky, 1979). This happens because of the unrealistic assumption of rationality (Rashid et al., 2019). The investors’ irrationality leads to the paradigm of behavioural finance (Kumar et al., 2016), which is linked with understanding the reasoning pattern of investors and affects their investment decision making (Mertzanis & Allam, 2018).
The present article focuses on one of the aspects of behavioural finance, that is, herd behaviour, which means imitating the actions of others, ignoring their own rational thinking and arriving at market consensus (Bikhchandani & Sharma, 2000). It is doing the same what every other person is doing even if private information does not favour it (Banerjee, 1992) and people responding in accordance with the majority of others around them, characterized by a lack of independent judgement or deliberation (Kanojia et al., 2020b). Individuals encounter comparable difficulties, which lead to similar options and as a result, similar payoffs (Bikhchandani et al., 1998). Investors feel optimistic while following the trend and rely on market sentiment for their investment decisions (Choi & Yoon, 2020). Herding opposes the rational asset pricing model.
Literature (Banerjee, 1992; Bikhchandani et al., 1992; Chevalier & Ellison, 1999; Hong et al., 2000; Scharfstein & Stein, 1990) suggests certain theories about herding. First, psychology effect leads to herding since sense of security is achieved by following the majority (Goldbaum, 2008). Second, it has been observed that informed investors would make a better investment decision rather than the uninformed ones, therefore, favouring information driven effect (Calvo & Mendoza, 2000). Reputation Effect constitutes the third theory, which suggests that mutual fund managers are trusted on account of their trading strategies, which builds their reputation (Swank & Visser, 2008). Investors do follow the herd in the same direction as they want some confirmation, which helps them to gain confidence during the periods of uncertainty (Nofsinger & Sias, 1999). Herding occurs because of various reasons, but the most obvious one is conformity with the society (West, 1988).
Herding is categorized into two parts: One is the spurious herding in which investors react to the information set and take the decisions following the same trend and second is the intentional herding where investors imitate others because they aim to do so (Bikhchandani & Sharma, 2000). The financial perspective of herding categorizes it into two dimensions: irrational herding in which the investors, not agreeing by this ideology, ignore their own analysis and rely on the market consensus (Christie & Huang, 1995). While rational herding is executed to protect one’s own reputation. This situation is compared with the situation of traders and agents whose performance is evaluated on their performance. In order to achieve good performance, they are likely to depend on others who have varied knowledge in this regard.
It is observed that investors tend to collect each and every information prior to making stock market investment (Mertzanis & Allam, 2018). In contrast to it, during extreme conditions, such activities of collecting information and then taking investment decisions accordingly, is quite impossible (Dhall & Singh, 2020). At times of stress, people start following others, which leads to inefficiency in the market (Nofsinger & Sias, 1999). Therefore, markets start destabilizing and prices tend to diverge from their fundamental value leading to low returns. Hence, biased earnings come into the picture, which weakens the financial market structure, making the entire financial system look fragile (Kumar et al., 2016).
A strand of literature, whether stock prices herd around the market, is available. Some studies (see, Abd-Alla, 2020; Chen, 2013; Choi & Yoon, 2020; Dhall & Singh, 2020; Economou, 2019; Luu & Luong, 2020; Poshakwale & Mandal, 2014; Vo & Phan, 2019) observed that during extreme conditions of market stress, individuals are more likely to follow the market consensus and tend to ignore their own beliefs. However, other studies (Chong et al., 2017; Garg & Gulati, 2013; Kumar et al., 2016; Yousaf et al., 2018) witnessed contradicting patterns of herd behaviour. The mixed evidence relating to herd presence is found with respect to time and market conditions.
Luu and Luong (2020) did sectoral analysis for the period 2000–2020 and examined the existence of herd behaviour in Taiwan and Vietnam stock markets during the pandemic influenza and COVID-19. Herd presence was found in insurance and materials in Vietnam and in real estate in Taiwan. Herding was noticed in the transportation industry in Vietnam and the energy industry in Taiwan during the influenza pandemic. Similarly, COVID-19 outbreak led to no herd behaviour in Vietnam while herding persists in the food and beverage industry of Taiwan. Furthermore, Choi and Yoon (2020) found herd presence in down market periods, high-trading volume periods and low and high quantiles in KOSPI and KOSDAQ stock markets for the period January 2003 to December 2018. The analysis also took into account the times of extreme crisis. Hence, herding formation was noticed in transportation industry in Vietnam and energy industry in Taiwan during Influenza pandemic. COVID-19 outbreak led to no herd behaviour in Vietnam while herding persists in Food Beverage Industry of Taiwan. Economou (2019) concluded that a glimpse of herding was witnessed in Romania. Bulgaria also witnessed herding during the low market volatility days for the period October 2000–December 2016. Vo and Phan (2019) conducted industry-wise analysis for the period 2005–2016 and observed the existence of herding in the banking sector of financial industry at times of rising market. However, weak evidence of herding was found in technological industry. Chen (2013) studied the herd behaviour with respect to developing, emerging and frontier markets for the period 1 January 2000–31 December 2009. The frontier markets witnessed the highest average daily return, followed by the emerging and developed markets. It was observed that herd behaviour persists in both up and down markets and also the tendency of investors to herd was more in response to bad news rather than good news.
Chang et al. (2000) tested the herd behaviour on account of investment behaviour seen in various international markets. The results indicated that equity return dispersions for the US, Hong Kong and Japan showed an increase, therefore, rejecting the presence of herd behaviour in these markets. While, the results regarding South Korea and Taiwan witnessed the presence of herd behaviour because they showed smaller equity return dispersions.
However, Christie and Huang (1995) examined the herd presence in equity returns. It was found that monthly data showed greater dispersions. Beta values from daily regression equations were positive, and thereby, strongly favoured the rational asset pricing model. Yousaf et al. (2018) stated that herd behaviour did not exist during extreme market movements as beta coefficients are positive. However, herding existed during low volume trade days and during crisis period, that is, 2007–2008. Chong et al. (2017), in their sample period for the period January 2000 to December 2011, found that coefficients of absolute market return were significantly positive in up and down markets, thereby rejecting the presence of herd behaviour.
While, in the Indian context, Kanojia et al. (2020b) observed no significant evidence of herding in the Indian stock market during different market conditions for the period 1 April 2009– 31 March 2018. Dhall and Singh (2020) could not capture herd presence in the Indian equity market for the period 1 January 2015–1 June 2020. However, when sectoral analysis was done, then instances of herd behaviour were found in auto industry, IT and pharma sectors in the post-COVID-19 times during bullish market conditions. Furthermore, during bearish market conditions, industry-wise analysis posit same results. Herd presence was found in media and entertainment industry. As opposed to it, Kumar et al. (2016) found no significant evidence of herd behaviour in the Indian stock market for the whole research period, including both up and down markets and dramatic price swings for the period 1 January 2008–31 December 2015. Garg and Gulati (2013) also witnessed increased equity dispersions during extreme market movements, thereby, rejecting any herd presence in the Indian stock market for the period April 2000–April 2013.
This study aims to contribute in terms of herd existence in up and down markets and during extreme periods of stress. It is beneficial to study the existence of herd behaviour in the Indian equity market as it would help the investors in predicting the future movement of the stocks correctly so that stocks could be valued properly and they might earn good returns. Both academicians and policy makers would get an insight from the study.
Hence, in the backdrop of the earlier discussion, this study is an attempt to contribute to the earlier yet unsettled debate by examining the herd behaviour in the Indian stock market using four categories of indices of the National Stock Exchange of India (NSE), namely broad market indices, sectoral indices, strategic indices and thematic indices from 1 January 2016–31 March 2022. This sample period has witnessed phenomenal growth in terms of trading volume, making it as a manifest period chosen for the testing of herd existence in India. To the best of our knowledge, this is the maiden study, which uses the data of all categories of indices of equity segment at the NSE. The study covers all categories of indices representing the equity segment at NSE as these serve as benchmark index for examining the performance of the stocks. It may also be noted that the previous studies (Abd-Alla, 2020; Chen, 2013; Choi & Yoon, 2020; Dhall & Singh, 2020; Economou, 2019; Garg & Gulati, 2013; Kanojia et al., 2020b; Kumar et al., 2016; Luu & Luong, 2020; Poshakwale & Mandal, 2014; Vo & Phan, 2019; Yousaf et al., 2018) have considered daily prices of individual stocks, while this article is considering stock market indices as a whole to examine whether it makes any difference in the findings and implications of herd behaviour in India. Therefore, the current study aims to fill this research gap and examine the herd existence in Indian equity market.
The rest of the article is organized as follows. The second section explains data description. The third section discusses research methodology, the fourth section provides results with interpretation, the fifth section concludes the study and discusses the future scope of the study.
Data Description
Data for this study has been extracted from the website of the NSE of India (
List of Broad Market Indices, Sectoral Indices, Strategic Indices and Thematic Indices.


Moreover, the Nifty 500 is used as a proxy index as it is a comprehensive index of 500 firms that account for 90% of India’s total market capitalization, making it a useful proxy index. Additionally, it represents 98% of total turnover of trades in India (Katarachia et al., 2018).
Research Methodology
This study is focused to examine the herding behaviour with the help of equity returns. In this study, five types of returns are calculated.
where Pt = closing price of stock at time t.
where Open t = opening price of stock at time t.
Closet−1 = closing price of stock at time t−1.
where High t = high price of stock at time t.
Low t = closing price of stock at time t.
To examine the herd behaviour in security prices, regression models suggested by Christie and Huang (1995) and Chang et al. (2000) are used. The first model tests whether the dispersions are lower during the times of extreme market conditions. It was argued that individual investors tend to ignore their own information, rely on others and behave accordingly in the stock market. As a result, the security returns will not deviate too far from the market and investors will invest keeping in mind the collective action of the market. In order to measure the proximity of individual returns to the market average, cross-sectional standard deviation is calculated with respect to the market return.
where CSSDt = Cross-Sectional Standard Deviation on day t; Rit = stock returns i at time t; Rmt = market return at time t; N = number of stocks.
Dispersions must be low to validate the herd presence. However, low dispersions do not guarantee the herd presence. Sometimes, lack of new information prevailing in the market leads to low dispersions and herding is not witnessed.
According to the asset pricing model assuming rationality, periods of market stress lead to increase in dispersions. In contrast, when herding exists, dispersions are lower. In order to test this, the level of dispersions is isolated in the extreme tails of market distribution to see whether the security returns are significantly different from the market return. This testing is done using the following regression model:
where CSSD is the Cross-Sectional Standard Deviation. ‘α’ coefficient denotes the average dispersions in the sample. ‘Up’ and ‘Down’ are two dummy variables. ‘Up’ refers to the dummy variable, which is equal to 1 when the daily market returns lie in the extreme upper tail of observation and otherwise 0. Similarly, ‘Down’ refers to the dummy variable, which is equal to 1 when the daily market returns lie in the extreme lower tail of the observation and otherwise 0.
This study uses extreme 5% criteria for the upper and lower tail of market returns distribution. The herd presence is validated when the β1 and β2 coefficients are significantly negative while positive coefficients of β1 and β2 will disconfirm any herd presence. Positive coefficients of β1 and β2 will indicate the high volatility among individual stock returns.
There are limitations to CSSD model. The CSSD model examines herding with respect to the extreme market conditions only and it is overshadowed due to the presence of outliers. These limitations are taken into account in CSAD model. CSAD model is proposed by Chang et al. (2000). This model extended the work of Christie and Huang (1995) and is less exposed to outliers. This model examines the non-linear relationship between equity return dispersions and the overall market return and uses CSAD instead of CSSD, which is defined as:
where CSADt = Cross-Sectional Absolute Deviation on day t; Rit = stock returns i at time t; Rmt = market return at time t; N = number of stocks.
It is observed that in the presence of herding, increase in market return leads to decrease in individual equity returns dispersions. This is in contradiction to the asset pricing model, which states that there is a linear relationship between equity return dispersions and market return. This linear relation will no longer hold good, when the market participants tend to follow the herd and imitate market behaviour. In order to check the validity, one more variable r2
m,t
become the part of the regression equation. The herding behaviour is examined using the following regression model:
where CSAD is the Cross-Sectional Absolute Deviation. rm, t is the cross-section average return of sample on day t. |rm,t| is the absolute market return at day t. r2 m,t is the squared value of the market return on day t.
A significantly negative γ3 coefficient implies the herd presence. This indicates the herd presence during extreme stress period and observes a non-linear relation between return dispersions and squared market return, thereby stating that investors typically ignore their own convictions and do what the market dictates while taking investment decisions. A significantly positive γ3 coefficient will indicate that market return will increase with the increase in CSAD, hence, giving evidence against herding.
Results and Interpretation
This study examines herding with the help of daily return, overnight return, intraday return, absolute market return and squared market return using the regression models suggested by Christie and Huang (1995) and Chang et al. (2000). Cross-Sectional Standard Deviation (CSSD) and Cross-Sectional Absolute Deviation (CSAD) are calculated using the above models. The lower the dispersions, the higher would be the chances of herd existence. Descriptive statistics are calculated with regard to cross-sectional standard deviation and cross-sectional absolute deviation using broad market indices, sectoral indices, strategic indices and thematic indices.
Table 2 provides the descriptive statistics of CSSD and CSAD for broad market indices, sectoral, strategic indices and thematic indices. The high difference between the maximum and minimum values of CSSD and CSAD indicates higher volatility in CSSD and CSAD. The value of kurtosis is more than 3, which indicates that the data does not follow the normal distribution. The higher values of skewness would suggest that the outliers form the part of dataset.
Descriptive Statistics (CSSD and CSAD).
• CSSD stands for cross sectional standard deviation.
• CSAD stands for cross sectional absolute deviation.
Furthermore, to examine the existence of herd behaviour first, CSSD regression is calculated by using the Christie and Huang (1995) model and results are presented in Table 3. In this model, beta coefficients are calculated. Significantly negative beta coefficients support herding in the stock market while positive beta coefficients reject the herd presence in the stock market. It is observed that in spite of significant market swings, herd behaviour is not observed in the Indian stock market.
CSSD Regression.
The significantly positive p-values are marked with asterisk (*). However, the significantly negative values depicting the herd presence are marked bold and with asterisk (*).
All beta coefficients are positive, except in the case of intraday return in extreme down movement of the market, thereby, rejecting the herd behaviour in the stock market, which implies that investors act rationally and do not imitate the actions of other investors. Herd presence is rejected as the return dispersions tend to increase during extreme market movements. This indicates investors react to bad news much briskly rather than good news (Chen, 2013). The findings of the study are consistent with Yousaf et al. (2018), Chong et al. (2017), Kanojia et al. (2020b), Kumar et al. (2016) and Garg and Gulati (2013). May be due to the short time frame, investors herd and follow the trend during intraday trading. However, when they have sufficient time to ponder, deliberate and analyse, they might take relatively independent investment/trading calls based on their research and analytical acumen.
Moreover, the results of CSAD regression turn out to be somewhat different. Herd behaviour is witnessed in few instances in the Indian equity market. The findings of CSAD regression of Chang et al. (2000) conform the findings of Christie and Huang (1995) with an exception of daily return, absolute market return and squared market return, which are presented in Table 4.
CSAD Regression.
• R stands for return
• AR stands for absolute return
• SR stands for squared return
• The significantly positive p-values are marked with asterisk (*). However, the significantly negative p-values depicting the herd presence are marked bold and with asterisk (*).
Herding is witnessed with significantly negative beta coefficients. However, herd presence is not found when beta coefficients are significantly positive. It is observed that herd presence is not validated and witnessed in the Indian equity market as all the coefficients, except few, are significantly positive. Although, a few coefficients of intraday return and squared market return are significantly negative. Both models observed consistent results thereby rejecting any herd presence in the Indian stock market during the selected sample period.
Conclusion
With the passage of time, the Indian financial sector has achieved great heights of growth, due to which, it has become an attraction for many international investors. Following the crowd and ignoring one’s own rationality constitutes herding. Herding exists because investors prefer to act in accordance with the majority rather than to stand alone. The absence of herding implies that investors perform rationally. However, this study aims to investigate the irrationality of investors by examining herd behaviour in the Indian equity market using broad market indices, sectoral indices, strategic indices and thematic indices of NSE. The calculated results failed to provide any evidence in favour of herding and support the theory of efficient market hypothesis. The results indicate that the Indian investors do not support herd mentality, rather take investment decisions on their own. Herding is an attribute of extreme market declines only.
The study has several implications for the policymakers, investors and regulators of the market as it would be helpful in correct valuation of stocks. These results can enable policy makers to design the reforms in the market microstructure.
Presence of herding in intraday return would help the arbitragers to act upon and book profits during short run caused due to price disequilibrium. In contrary to this, such opportunity is not available in daily, overnight, absolute and squared market returns. The reasons for absence of herding in the Indian stock market can be due to the participation of active traders in the market, who are institutional investors. These investors/traders drive the market as they may have the access to private information well before it reaches the retail investors. Such informational asymmetry may be the reason behind the absence of herding in the Indian equity market. Regulators are taking out various measures like improving transparency, full disclosure with respect to trading patterns, increase in trading hours, etc., which shall help to improve information symmetry in the market, resulting in informed decision making by the investors.
From the future scope point of view, this study examines the herd behaviour only in equity stocks, however, herd behaviour can also be examined for commodities, currencies, cryptocurrencies and derivatives.
Footnotes
Declaration of Conflicting Interests
The authors declared no potential conflicts of interest with respect to the research, authorship and/or publication of this article.
Funding
The authors received no financial support for the research, authorship and/or publication of this article.
