Mean reversion and long memory in African stock market prices

We examine the behavior of stock market prices in several African countries by means of fractionally integrated techniques. In doing so, we can test for mean reversion in these markets. Our results can be summarized as follows: we cannot find evidence of mean reversion in any single market, and evidence of long memory returns (i.e., orders of integration above 1 in the logged stock prices) is obtained in the cases of Egypt and Nigeria, and, in a lesser extent in Tunisia, Morocco and Kenya. Permitting the existence of a structural change, the break dates take place in the earlier 2000s in the majority of the cases, and evidence of mean reversion seems to have taken place in the periods before the breaks in most of the countries. If we focus on the absolute and squared returns, evidence of long memory is obtained in Nigeria and Egypt. Thus, for these two countries, a long memory model incorporating positive fractional degrees of integration in both the level and the volatility process should be considered.     

The VIX,the variance premium and stock market volatility

We decompose the squared VIX index, derived from US S&P500 options prices, into the conditional variance of stock returns and the equity variance premium. We evaluate a plethora of state-of-the-art volatility forecasting models to produce an accurate measure of the conditional variance. We then examine the predictive power of the VIX and its two components for stock market returns, economic activity and financial instability. The variance premium predicts stock returns while the conditional stock market variance predicts economic activity and has a relatively higher predictive power for financial instability than does the variance premium.     

An analysis of firm and market volatility

In this paper, using time series data for the period 2 January 1998 to 31 December 2008 for 560 firms listed on the NYSE, we examine whether firm volatility is related to market volatility. The main contribution of this paper is that we develop an analytical framework motivating the firm-market volatility relationship. We present three new findings on volatility. First, we discover significant evidence of common volatility; for 12 out of 14 sectors, market volatility has a statistically significant effect on firm volatility for at least 50 percent of firms. Second, we discover significant evidence of size effects: for small-sized firms, there is weak evidence of commonality in volatility, while for large-sized firms there is high evidence (for as much as 75 percent of firms) of commonality in volatility. Third, we find that market volatility predicts firm volatility for firms belonging to five of the 14 sectors.     

The outbreak of COVID-19 and stock market liquidity: Evidence from emerging and developed equity markets

The outbreak of the novel corona virus has heightened concerns surrounding the adverse financial effects of the outbreak on stock market liquidity and economic policies. This paper contributes to the emerging strand of studies examining the adverse effects of the virus on varied aspect of global markets. The paper examines the causality and co-movements between COVID-19 and the aggregate stock market liquidity of China, Australia and the G7 countries (Canada, France, Italy, Japan, Germany, the UK and the US), using daily three liquidity proxies (Amihud, Spread and Traded Value) over the period December 2019 to July 2020. Our empirical analysis encompasses wavelet coherence and phase-differences as well as a linear Granger causality test. Linear causality test results suggest that a causal relationship exists between the number of cases of COVID 19 infections and stock market liquidity. To quantitatively examine the degree of causality between COVID-19 outbreak and stock market liquidity, we employ the continuous wavelet coherence approach with results revealing the unprecedented impact of COVID-19 on stock market liquidity during the low frequency bands for countries that were hard hit with the COVID-19 outbreak, i.e., Italy, Germany, France, the UK and the US. Further, evidence shows that there is a heterogeneous lead-lag nexus across scales for the entire period of the study.     

Order aggressiveness, pre-trade transparency, and long memory in an order-driven market

Recent empirical research has documented that the state of the limit order book influences stock investors' strategies. Investors place more aggressive orders when the same side of the order book is thicker, and less aggressive orders when it is thinner. We conjecture and demonstrate that this behavior is related to long memories of trading volume, volatility, and order signs in stock markets. We investigate our conjecture in two types of artificial stock markets: a transparent market, in which agents observe all limit orders on both sides of the book and order volumes at those prices before they trade; and a less transparent market, in which agents observe only the best five bid and ask quotes with the depth available at these limit prices. The first market structure resembles certain actual stock exchanges in the level of pre-trade transparency, such as the Australian Stock Exchange, NYSE OpenBook, and the London Stock Exchange, whereas the second market structure is consistent with stock exchanges such as Euronext Paris, the Toronto Stock Exchange, the Tokyo Stock Exchange, and Hong Kong Exchanges and Clearing. We demonstrate that our long memory results are robust with different levels of pre-trade transparency, implying that the strategy constructed by the state of the order book is key for explaining long memories in many actual stock exchanges.     

Information disclosure ratings and managerial short-termism: An empirical investigation of the Chinese stock market

Information asymmetry between managers and outside investors creates agency problems and impedes efficient capital allocation. Information disclosure is critical in alleviating information asymmetry in capital markets. This study investigates the effect of information asymmetry on managerial short-termism by examining information disclosure ratings (IDRs). Using real earnings management as a proxy for managerial short-termism, our analysis of a sample of Chinese A-share companies during 2001–2018 indicates that high IDRs mitigate managerial short-termism. The results also indicate that the effect of IDRs in reducing managerial short-termism is driven mainly by stock liquidity. This conclusion holds after consideration of endogeneity and application of two-stage least-squares and generalized method of moments methods, adjustment of the definition of IDRs, consideration of alternative proxies for managerial short-termism, and control for firm characteristics that might affect the extent of managerial short-termism. This study also examines the effects within three subsamples: companies listed on the Shenzhen Stock Exchange main board, small and medium enterprise board, and growth enterprise market board. IDRs substantially reduce managerial short-termism among firms listed on all three boards. These findings indicate that enterprises have corrected previous internal governance problems, and IDRs have helped to improve internal governance through stock liquidity. Therefore, external supervision also helps to reduce the agency problem of managerial short-termism.

     

Distribution theory for the studentized mean for long,short, and negative memory time series

We consider the problem of estimating the variance of the partial sums of a stationary time series that has either long memory, short memory, negative/intermediate memory, or is the first-difference of such a process. The rate of growth of this variance depends crucially on the type of memory, and we present results on the behavior of tapered sums of sample autocovariances in this context when the bandwidth vanishes asymptotically. We also present asymptotic results for the case that the bandwidth is a fixed proportion of sample size, extending known results to the case of flat-top tapers. We adopt the fixed proportion bandwidth perspective in our empirical section, presenting two methods for estimating the limiting critical values—both the subsampling method and a plug-in approach. Simulation studies compare the size and power of both approaches as applied to hypothesis testing for the mean. Both methods perform well–although the subsampling method appears to be better sized–and provide a viable framework for conducting inference for the mean. In summary, we supply a unified asymptotic theory that covers all different types of memory under a single umbrella.     

Bayesian time series analysis of periodic behaviour and spectral structure

Analysis, model selection and forecasting in univariate time series models can be routinely carried out for models in which the model order is relatively small. Under an ARMA assumption, classical estimation, model selection and forecasting can be routinely implemented with the Box–Jenkins time domain representation. However, this approach becomes at best prohibitive and at worst impossible when the model order is high. In particular, the standard assumption of stationarity imposes constraints on the parameter space that are increasingly complex. One solution within the pure AR domain is the latent root factorization in which the characteristic polynomial of the AR model is factorized in the complex domain, and where inference questions of interest and their solution are expressed in terms of the implied (reciprocal) complex roots; by allowing for unit roots, this factorization can identify any sustained periodic components. In this paper, as an alternative to identifying periodic behaviour, we concentrate on frequency domain inference and parameterize the spectrum in terms of the reciprocal roots, and, in addition, incorporate Gegenbauer components. We discuss a Bayesian solution to the various inference problems associated with model selection involving a Markov chain Monte Carlo (MCMC) analysis. One key development presented is a new approach to forecasting that utilizes a Metropolis step to obtain predictions in the time domain even though inference is being carried out in the frequency domain. This approach provides a more complete Bayesian solution to forecasting for ARMA models than the traditional approach that truncates the infinite AR representation, and extends naturally to Gegenbauer ARMA and fractionally differenced models.     

An analysis of the capital asset pricing model in the Egyptian stock market

This paper offers evidence confirming the validity of applying modern portfolio theory and capital asset pricing models to the emerging stock market of Egypt. The results indicate that market risk, as measured by beta and preference for skewness, seems to play a significant role in the returns dynamics in the Egyptian stock market. There is a significant and positive premium for companies with positive skewness. With regard to the return-risk trade off, the results indicate that a portfolio that was based on consumer staples and financial companies (mainly banks) with low betas had outperformed a portfolio containing construction, materials, hotels, and weaving companies with larger betas. Historically, the government's nationalizations that took place, between the mid fifties to the mid sixties, had adversely affected companies in the industrial and construction sectors more than consumer staples companies and banks. This could explain why lower beta companies were observed more in consumer staples, banks, and pharmaceuticals.     

Value investing anomalies in the European stock market: Multiple Value, Consistent Earner, and Recognized Value

Empirical academic studies have consistently found that value stocks outperform glamour stocks and the market as a whole. This article extends prevailing research on existing value anomalies. It evaluates simple value strategies for the European stock market (compared to many other studies that test market data on a country-by-country basis) as well as sophisticated multi-dimensional value strategies that also include capital return variables (Consistent Earner Strategy) and momentum factors (Recognized Value Strategy), the latter reconciling intermediate horizon momentum and long-term reversals of behavioral finance theories. It can be shown that these “enhanced” value strategies can produce superior returns compared to returns of the whole market or “simple” value strategies without capturing higher risks applying traditional risk measures.     

Adoption of inflation targeting and tax revenue performance in emerging market economies: An empirical investigation

This paper investigates whether the adoption of inflation targeting (IT), by strengthening central bank independence and maintaining inflation at low levels, has encouraged the governments of emerging economies to improve the collection of domestic tax revenue in order to recoup the loss of seigniorage revenue. Using the propensity score matching methodology, a micro-econometric methodology recently used in macroeconomics, we evaluate the ‘treatment effect’ of IT on fiscal mobilization in emerging countries that have adopted this monetary policy framework. Our empirical analysis, conducted on a sample of 59 countries (19 IT and 40 non-IT countries) for the period from 1980 to 2009, shows that on average IT adoption has had a large and significant positive effect on public revenue collection. Our results are confirmed by extensive robustness tests.     

The effect of housing and stock market wealth on consumption in emerging and developed countries

This study examines the long- and short-run relationship between private consumption, housing wealth, stock market wealth and income. In order to asses this relationship empirically, we use pooled mean group estimators of dynamic heterogeneous panel data on a sample of 30 developed and emerging economies. The sample countries are segmented into three separate panels: a developed bank-based panel, a developed market-based panel, and an emerging bank-based panel. Empirical estimates support the existence of long- and short-run stock market wealth effects in both groups of developed countries, with the effect being particularly strong in the developed market-based countries. A moderate long-run housing wealth effect is confirmed only for the developed bank-based countries, while a very strong short-run housing wealth effect is present in the developed market-based countries. As far as the emerging countries are concerned, the evidence is somewhat inconclusive, but it does seem to suggest that both wealth effects are effective in the long run, with housing wealth being more dominant.     

中国股票市场风险和收益风格效应的非参数检验

本文利用Kendall协同系数检验考察我国股票市场风险和收益的风格效应。通过实证研究首次发现各风格指数的收益率、总风险及指数特有风险均具有明显的分层结构,风格效应显著。对影响风险和收益的风格因素进行的分析表明:股票风险受规模因素的影响十分明显;而股票回报率受价值因素的影响比较显著,受规模因素的影响不明显。并进一步用Spearman相关系数考察了风险与收益之间的秩相关性。本文研究结果对资产配置和风险监管等问题具有参考价值。     

Evaluating cost efficiency and returns to scale in the Life Insurance Corporation of India using data envelopment analysis

This paper applies a new variant of data envelopment analysis model to examine the performance of Life Insurance Corporation (LIC) of India. The findings show a significant heterogeneity in the cost efficiency scores over the course of 19 years. A decline in performance after 1994-1995 can be taken as evidence of increasing allocative inefficiencies arising from the huge initial fixed cost undertaken by LIC in modernizing its operations. A significant increase in cost efficiency in 2000-2001 is, however, cause for optimism that LIC may now be realizing a benefit from such modernization. This will stand them in good stead in terms of future competition. Results from a sensitivity analysis are in broad agreement with the main findings of this study.     

The costs of suboptimal dynamic asset allocation: General results and applications to interest rate risk, stock volatility risk, and growth/value tilts

The recent theoretical asset allocation literature has derived optimal dynamic investment strategies in various advanced models of asset returns. But how sensitive is investor welfare to deviations from the theoretically optimal strategy? Will unsophisticated investors do almost as well as sophisticated investors? This paper develops a general theoretical framework for answering such questions and applies it to three specific models of interest rate risk, stochastic stock volatility, and mean reversion and growth/value tilts of stock portfolios. Among other things, we find that growth/value tilts are highly valuable, but the hedging of time-varying stock risk premia is less important.     

The effect of operational slack,diversification, and vertical relatedness on the stock market reaction to supply chain disruptions

This paper empirically examines whether operational slack, business diversification, geographic diversification, and vertical relatedness influence the stock market reaction to supply chain disruptions. The results are based on a sample of 307 supply chain disruptions announced by publicly traded firms during 1987–1998. Our analysis shows that firms with more slack in their supply chain experience less negative stock market reaction. The extent of business diversification has no significant effect on the stock market reaction. Firms that are more geographically diversified experience a more negative stock market reaction. We find that firms with a high degree of vertical relatedness experience a less negative stock market reaction. These results have important implications on how firms design and operate their supply chains to mitigate the negative effect of supply chain disruptions.     

The political uncertainty and stock market behavior in emerging democracy: the case of Taiwan

This paper examines the congressional effect between the pre- and post-democratization on the stock market by the asymmetric Generalized Autoregressive Conditional Heterosce desticity (GARCH) model in the period 1984–2004. The results found that the congressional effect is negative effect on stock returns but volatility is not significant. However, the democratic effect on stock returns is negative and increased of volatility. Moreover, the congressional effect on stock market returns following democratization significantly exceeds that before democratization, but have no significant effect for the volatility in the same circumstances. These results provide evidences consistent with the contention of liberalization (Hayek, Am. Econ. Rev. 35, 519–530, Individualism and Economic order, The university of Chicago press, Chicago, London, 1945, 1948; Popper, The open society and its Enemies, Princeton university, NJ, 1950).     

How supervisors set the tone for long hours: Vicarious learning,subordinates' self-motives and the contagion of working hours

This paper develops a theoretical model that highlights the mechanisms underlying the contagion of long working hours from supervisors to subordinates at different stages of their relationship. Drawing upon social learning theory, we suggest that subordinates mimic the supervisor's working hours through vicarious learning. Focusing first on the role-taking stage of the supervisor-subordinate relationship, we identify four factors, namely supervisor's perceived status, subordinate's work centrality, congruence between organizational norms and supervisor's working hours, and subordinate's identification with the supervisor, that may influence the perceived desirability of adopting the supervisor's working hours. We then examine the relative influence of each of these factors through the lens of subordinates' self-motives. Turning, next, to the routinized supervisor-subordinate relationship, we elaborate on how social contagion may evolve over time. Lastly, the implications of our model as well as future research avenues are presented.     

Accumulation, Technical Progress, and Increasing Returns in the Economic Growth of East Asia

Adopting homothetic variable returns to scale functional specifications, this study identifies the returns to scale in the aggregate production functions of four East Asian newly industrialized economies–Hong Kong, Korea, Singapore, and Taiwan–and the Group of Five economies based on a maximum likelihood estimation. The study finds evidence of increasing returns in the early developmental stage of the East Asian economies. Separating out the scale contribution from the non-scale factor contributions, the decomposition of the sources of East Asian economic growth differs significantly from the conventional constant returns to scale results, indicating that the role of technical progress is overestimated when constant returns to scale is assumed.     

Expenditure allocation across nondurables,services, durables and savings: An empirical study of separability in the long run

The separability of categories of consumption expenditures and savings are empirically examined in the context of an error-correction model of aggregate quarterly expenditure allocations in Canada. Some evidence is found for separability of consumption allocations from savings in both the long run structure and short run dynamics of the model lending some support to the use of the assumption in modelling consumption behaviour.