Tests of random walks and market efficiency in Latin American stock markets: An empirical note. Discussion Paper No. 157 (original) (raw)

An empirical note on the random walk behaviour and market efficiency of Latin American stock markets

This note examines the weak-form market efficiency of Latin American equity markets. Daily returns for Argentina, Brazil, Chile, Colombia, Mexico, Peru and Venezuela are examined for random walks using serial correlation coefficient and runs tests, Augmented Dickey-Fuller (ADF), Phillips-Perron (PP) and Kwiatkowski, Phillips, Schmidt and Shin (KPSS) unit root tests and multiple variance ratio (MVR) tests. The results, which are in broad agreement across the approaches employed, indicate that none of the markets are characterised by random walks and hence are not weak-form efficient, even under some less stringent random walk criteria.

Random Walks and Market Efficiency Tests of Latin American Emerging Equity Markets: A Revisit

The Financial Review, 1999

The few existing studies on equity price dynamics and market efficiency for Latin American emerging equity markets show conflicting results. This study uses multiple varianceratio and auto-regressive fractionally integrated moving-average tests and new data (U.S. dollar-based national equity indices for the 1987-1997 period) to clarify these results. Documented evidence shows that equity prices in major Latin American emerging equity markets-Argentina, Brazil, Chile and Mexico-follow a random walk, and that they are, generally, weak-form efficient. In sum, therefore, the evidence suggests that international investors in these markets cannot use historical information to design systematically profitable trading schemes because future long-term returns are not dependent on past returns.

Random walks and market efficiency tests: evidence from emerging equity markets

Review of Quantitative Finance and …, 1999

We use the multiple variance-ratio test of to examine the stochastic properties of local currency-and US dollar-based equity returns in 15 emerging capital markets. The technique is based on the Studentized Maximum Modulus distribution and provides a multiple statistical comparison of variance-ratios, with control of the joint-test's size. We ®nd that the random walk model is consistent with the dynamics of returns in most of the emerging markets analyzed, which contrasts many random walk test results documented with the use of single variance-ratio techniques. Further, a runs test suggests that most of the emerging markets are weak-form ef®cient. Overall, our results suggest that investors are unlikely to make systematic nonzero pro®t by using past information in many of the examined markets, thus, investors should predicate their investment strategies on the assumption of random walks. Additionally, our results suggest exchange rate matters in returns' dynamics determination for some of the emerging equity markets we analyzed.

Weak-form market efficiency in Asian emerging and developed equity markets: Comparative tests of random walk behaviour

This paper examines the weak-form market efficiency of Asian equity markets. Daily returns for ten emerging (China, India, Indonesia, Korea, Malaysia, Pakistan, the Philippines, Sri Lanka, Taiwan and Thailand) and five developed markets (Australia, Hong Kong, Japan, New Zealand and Singapore) are examined for random walks using serial correlation coefficient and runs tests, Augmented Dickey-Fuller, Phillips-Perron and Kwiatkowski, Phillips, Schmidt and Shin unit root tests and multiple variance ratio tests. The serial correlation and runs tests conclude that all of the markets are weak-form inefficient. The unit root tests suggest weakform efficiency in all markets, with the exception of Australia and Taiwan. The results from the more stringent variance ratio tests indicate that none of the emerging markets are characterised by random walks and hence are not weak-form efficient, while only the developed markets in Hong Kong, New Zealand and Japan are consistent with the most stringent random walk criteria.

Testing Stock Market Efficiency in Emerging Financial Markets: A Comparative Test of Random Walk Behaviour (RWB) in High and Low Volatility Regimes’

Abstract One of the most contentious issues in finance is possibly whether the financial markets are efficient or not. When determining the market efficiency, Efficient Market Hypothesis (EMH) has attracted the interest of greater number of academics and practitioners in empirical finance literature. However, empirical studies of the market efficiency in the two regimes of high and low volatility are still unexplored. Thus, this study attempts to identify the random work behaviour in high and low volatility regimes in emerging financial markets namely, India, China, Indonesia, Korea, Malaysia, Taiwan and Philippine. Returns of daily, weekly and monthly of the market portfolios from 2000 to 2010 are used for the investigation. Primarily, the Iterated Cumulative Sums of Squares (ICSS) algorithm and GARCH regression are used to identify the volatility breaks and for the purpose of subdividing the original series in to low volatile and high volatile regimes. Subsequently, popular econom...

Random Walks and Market Efficiency Tests: Evidence for Us and African Capital Markets

5th EMAN Selected Papers (part of EMAN conference collection), 2021

The 2020 Russia-Saudi Oil Price War was an economic war triggered in March 2020 by Saudi Arabia in response to Russia’s refusal to reduce oil production to keep oil prices at a moderate level. This economic conflict resulted in a sharp drop in the price of oil in 2020, as well as crashes in international markets. In the light of these events, our aim was to test the efficient market hypothesis, in its weak form, in the stock markets of Botswana (BSE), Egypt (EGX 100), Kenya (NSE 20), Moroccan All Shares (MASI), Tunisia (Tunindex), and the MARKET of the USA (DOWJONES INDUSTRIALS), in the period of Septem¬ber 2, 2019 to January 11, 2021. The results therefore support the evidence that the random walk hypoth¬esis is not supported by the financial markets analyzed in this period of global pandemic. The values of variance ratios are lower than the unit, which implies that the yields are autocorrelated in time and, there is reversal to the mean. In order to validate the results, we estima...

Testing the Random Walk Behavior and Efficiency of the Egyptian Equity Market

2011

The main objective of this study is to investigate whether prices in Egypt emerging equity market follow a random walk process as stated by the efficient market hypothesis. Therefore, this study examines the weak-form of market efficiency in Egypt stock market by testing the random walk hypothesis (RWH) through multi-approaches, specifically unit root, runs and variance ratio tests on the daily price of EGX 30 index of Egypt equity market over the period from January 1998 until December 2010. The empirical results reject the RWH at the weak-form level, indicating that stock prices do not fully reflect all historical information.

Efficiency Tests In the Iberian Stock Markets Testes De Eficiência Aos Mercados De Acções Ibéricos

This paper investigates the efficiency of the two major stock indexes of the Iberian Peninsula, the Portuguese Stock Index (PSI-20) and the Spanish Stock Index (IBEX-35). We used daily data from Serial correlations, unit root tests and variance ratio tests are used to test the efficiency of these two stock indexes. Although the complementary of these tests, we used all of them to get a higher robustness of the conclusions. We examined serial correlation coefficients for successive stock index changes to test whether they are statistically equal to zero to establish the random walk nature of stock indexes. The augmented Dickey-Fuller (ADF) test are used to test the null hypothesis that the series has a unit root and the variance ratio tests are used to examine the random walk hypothesis for the series of these two stock indexes.

Random Walks and Market Efficiency Tests: Evidence from Emerging Equity Market of Kuwait

European Journal of Economics, Finance and Administrative Sciences, 2011

This paper examines the random walk theory and the efficient market hypothesis of Kuwait equity market. The study uses daily observation of Kuwait stock exchange (KSE) index from 17 June 2001 to 8 December 2010. Parametric and nonparametric tests are utilized to examine the randomness of KSE. The parametric tests include the serial correlation test, and the Augmented Dickey-Fuller (unit root) test. The nonparametric tests employ the runs test and Phillips-Peron (PP) test. The empirical findings suggest the KSE is informationally inefficient at the weak-form level indicating that prudent investors will realize abnormal returns by using historical data of stock prices and trading volume.