Return Correlations Research Articles

Modeling dynamic higher-order comoments for portfolio selection based on copula approach

This paper introduces a novel approach to estimating time-varying higher-order comoments from a theoretical standpoint. We present how to estimate the dynamic higher-order comoments of asset returns under the copula framework, which builds on the ARCD and copula-DCC models to capture the time variation in higher-order moments and correlations of asset returns. Additionally, the elements in the coskewness and cokurtosis matrices are calculated by the double, triple, and quadruple integrals associated with the joint density function of asset returns. The empirical application to five international market indexes shows that the portfolio with time-varying higher-order comoments estimated by the copula approach significantly outperforms equally weighted and mean–variance strategies in economic performance. The robustness analysis verifies the validity and robustness of the proposed estimation method. Our research offers fresh insights for portfolio analysis and risk management decision-making in practical scenarios.

Revisiting elastic string models of forward interest rates

Twenty five years ago, several authors proposed to describe the forward interest rate curve (FRC) as an elastic string along which idiosyncratic shocks propagate, accounting for the peculiar structure of the return correlation across different maturities. In this paper, we revisit the specific ‘stiff’ elastic string field theory of Baaquie and Bouchaud [Stiff field theory of interest rates and psychological future time. Wilmott Mag., 2004, 2–6] in a way that makes its micro-foundation more transparent. Our model can be interpreted as capturing the effect of market forces that set the rates of nearby tenors in a self-referential fashion. The model is parsimonious and accurately reproduces the whole correlation structure of the FRC over the time period 1994–2023, with an error around 1% and with only one adjustable parameter, the value of which being very stable across the last three decades. The dependence of correlation on time resolution (also called the Epps effect) is also faithfully reproduced within the model and leads to a cross-tenor information propagation time on the order of 30 minutes. Finally, we confirm that the perceived time in interest rate markets is a strongly sub-linear function of real time, as surmised by Baaquie and Bouchaud [Stiff field theory of interest rates and psychological future time. Wilmott Mag., 2004, 2–6]. In fact, our results are fully compatible with hyperbolic discounting, in line with the recent behavioral Finance literature Farmer and Geanakoplos [Hyperbolic Discounting is Rational: Valuing the Far Future with Uncertain Discount Rates, Cowles Foundation Discussion Papers, 2009 (Cowles Foundation for Research in Economics, Yale University)].

Quantitative easing and correlation dynamics in the aftermath of the Great Recession: A dynamic conditional correlation with exogenous variables approach

AbstractIdentifying the effects of quantitative easing (QE) on asset return correlations is critical to assessing such policies’ impact across financial markets. In this paper, we use a dynamic conditional correlation model that allows us to measure the impact of unconventional monetary policy on time‐varying correlations. Our results suggest that QE significantly affected correlations between stocks and bonds after the Great Recession via short‐term portfolio balance effects. The findings are critical for policy‐makers and practitioners alike. Central banks should consider the impact of monetary policy on asset correlations in their cost–benefit analyses. Likewise, portfolio managers are encouraged to factor in the effects of monetary policy on correlations to optimize portfolios and reduce potential losses strategically.

Information Spillovers at Earnings Announcements

ABSTRACTResearch documents price co‐movements, or “spillovers,” between focal firms and their peers at focal firms’ earnings announcements. We find that both signed and absolute co‐movements between focal‐ and peer‐firm returns are significantly lower at earnings‐announcement dates compared to other dates. Analytically, we demonstrate that co‐movements do not necessarily indicate common information; instead, co‐movements measure the relative proportion of focal firm‐specific information to common information in focal‐firm earnings announcements. We study three settings where information transfers might be higher: when focal firms report significant earnings surprises, are industry leaders, or share correlated earnings patterns with peer firms. We continue to find lower return correlations during focal‐firm earnings announcements. We conduct two alternative tests but fail to find evidence that common information released during focal‐firm earnings announcements is significantly greater than on other days. These results raise doubt about the extent of the information externality attributable to financial‐report releases.

Interconnectedness of European insurers and cat shocks contagion effects

PurposeThe purpose of this paper is to examine the evolution of interconnectedness of European insurers among themselves, as well as with other non-financial firms, for the period 2000–2021 and to analyze the stock return movements around the costliest catastrophic events (hurricanes) in the past two decades.Design/methodology/approachThis paper follows the “simple” approach of Patro et al.(2013) and examines the daily stock return correlations of the largest 30 insurers and the largest 30 non-financial firms headquartered in Europe. In addition, the study uses event study methodology to examine stock return movements around the costliest hurricanes.FindingsWe find that the European insurance sector has become highly interconnected during the past two decades; however, its increasing connectedness with non-financial firms is limited to a few firms. In addition, we find weak evidence of the destabilizing effects of catastrophic events on European insurers and non-financial firms; however, the potential for cat risk contagion effects exists as the insurance industry becomes heavily interconnected.Originality/valueThe extant literature is largely concerned with the contribution of the insurance sector to the systemic risk of the financial sector. We focus on a specific region (Europe) and analyze the evolution of interconnectedness of the largest insurers within the insurance sector as well as with the largest non-financial firms encapsulating important crisis periods. In addition, we relate to the literature that examines the market reactions around catastrophic events to test the relevance of traditional insurance activities in instigating potential contagion shocks.

Understanding co-movements based on heterogeneous information associations

Both systematic and idiosyncratic information dissemination contribute to assets co-movement. To proxy for co-movement based on heterogeneous information diffusion, we construct two-layer network structures in terms of the correlations of systematic and idiosyncratic returns for Fama–French 49 industry portfolios. We further delve into the co-movement structures by studying their dynamics and interactions in terms of topological properties at both the system and individual levels. Our findings reveal the following: (1) Co-movement structures exhibit temporal changes and are closely associated with major risk events. (2) At the system level, there is time-varying mutual Granger causality between co-movement structures, particularly during or after recession periods. (3) At the individual level, we identify statistically significant but economically insignificant interplay between the two co-movement structures. Moreover, the co-movement structure based on systematic information diffusion is mainly influenced by industry-level characteristics, including idiosyncratic momentum, idiosyncratic volatility, and market beta. These results deepen our understanding of asset co-movement structures and bear significance for asset allocation and risk management practices.

Comomentum in China: Inferring arbitrage activity from return correlation

This paper investigates whether arbitrageurs can have a destabilizing effect on the Chinese stock market. We use comomentum defined as high-frequency abnormal return correlation among stocks to measure arbitrage activity. In contrast to the findings of Lou and Polk (2022), we find that the returns on momentum stocks exhibit long-term stabilization in China, regardless of whether comomentum is higher or lower. The results suggest that fluctuations in arbitrage activity do not serve as predictive indicators for changes in long-term momentum returns in the Chinese stock market. These results further emphasize the missing effect of the momentum strategy in the Chinese market.

The origin of return correlation networks

Abstract Financial networks are constructed from asset price comovements. There is a large literature that takes these networks as given, for example, for portfolio optimization. But what exactly is the origin of these networks? We exploit a unique database with matched asset price and order imbalance data, allowing us to observe the trade orders placed and reveal excess demands along with the resulting prices. Empirically, we find that order imbalance comovement has a positive and statistically significant effect on return comovement. Filtering out the latent market factors from both order imbalance and return leads to a drastic drop in explanatory power. We infer that the market factor of order imbalance is the primary driver of return comovement—robust to model specifications as well as fixed effects. We present complementary results with market volatility and the decomposition of traders in terms of strategic heterogeneity. Our work brings forth the role of order imbalance networks in explaining asset return networks.

The historical transition of return transmission, volatility spillovers, and dynamic conditional correlations: A fresh perspective and new evidence from the US, UK, and Japanese stock markets

<abstract> <p>This paper quantitatively investigated the historical transition of return transmission, volatility spillovers, and correlations between the US, UK, and Japanese stock markets. Applying a vector autoregressive (VAR)-dynamic conditional correlation (DCC)-multivariate exponential generalized autoregressive conditional heteroscedasticity (MEGARCH) model, we derived new evidence for four historical periods between 1984 and 2024. First, we found that the return transmission from the US to the other markets has historically become stronger, whereas recently, the return transmission from the UK to the US has disappeared. Second, we clarified that volatility spillovers from the US to the other markets have historically become stronger, whereas recently, volatility spillovers from the UK to the US have also disappeared. Third, our analyses of the historical constant correlations and DCCs revealed that stock market connectedness has gradually tightened between the US and Japan and between the UK and Japan, whereas recently, the connectedness between the US and UK has weakened. Fourth, our VAR-DCC analyses also revealed that volatility spillovers between the US, UK, and Japanese stock markets have been asymmetric. Fifth, we further showed that the skew-<italic>t</italic> errors incorporated into our VAR-DCC model are effective in estimating the dynamic stock return linkages between the US, the UK, and Japan. Finally, based on our findings, we derived many significant and beneficial interpretations and implications for historically and deeply considering return transmission, volatility spillovers, and DCCs between international stock markets.</p> </abstract>

US and China’s Stock Markets Correlation of Return and Volatility: Evidence from Time Series Model

US and China’s Stock Markets Correlation of Return and Volatility: Evidence from Time Series Model

Who participates in corporate income tax consolidation?: Evidence from Japan

When a group of affiliated corporations can file a single tax return based on a combined income, what types of groups would take up the option? This study empirically analyzes decisions to participate in a single-jurisdiction consolidated tax filing. The data consists of 2,782 Japanese corporate groups headed by publicly-traded corporations observed from 2002 to 2007. Results indicate a higher likelihood of participation among groups characterized by low correlation in returns among group members, high variance in returns, many subsidiaries, and losses accumulated in parents. The significant influence of variance and covariance of returns suggests that a consolidation scheme improves the efficiency of a corporate income tax by reducing profit shifting.

Correlation of Doppler ultrasound sphygmomanometer needle oscillation and audible pulse return with invasive systolic blood pressure in anaesthetised dogs: preliminary results

Correlation of Doppler ultrasound sphygmomanometer needle oscillation and audible pulse return with invasive systolic blood pressure in anaesthetised dogs: preliminary results

Economic integration and consumption risk sharing: A comparison of Eurozone and OECD countries

Economic theory predicts that economic integration can facilitate improvements in international consumption risk sharing. We test this proposition by comparing risk sharing among Eurozone members and members of the Organisation for Economic Co-operation and Development (OECD) using a dynamic common correlated effects mean group estimator (DCCEMG). The results reveal that the OECD members outperform the Eurozone members in terms of short run and long run risk sharing, despite the barriers to risk sharing being considerably lower among the latter. We attribute this outcome to lower business cycle synchronization and stock return correlations among OECD members, which creates better opportunities to share risk within the group. The results highlight the trade-off between the benefits of business cycle synchronization and international risk sharing. More tightly integrated economies, facilitate trade in assets that promotes better portfolio diversification, while at the same time are characterized by higher business cycle synchronization that depletes agents of risk sharing opportunities. Consequently, our results give strong support to the hypothesis of “diminishing international diversification potential”. However, the benefits associated with the improved risk sharing are increasing with the number of countries in the monetary union.

The effects of fund commonality in mutual fund families on fund operating expenses and return correlations:

This article examines the effects of the commonality of mutual funds within a fund family, which is measured by common stock holdings and multi-fund management, on fund operating expenses and return correlations. For U.S. equity funds during the period of 2001–2006, we find that common stock holdings and multi-fund management are negatively related to fund operating expenses but positively related to the correlation of fund return residuals, which increases the correlation of fund returns. Additionally, we find that the fund commonalities can have negative net effects on risk-adjusted returns of a portfolio with equity funds that have different investment objectives.

Foreign investors, rebalancing trades, and increases in U.S.-Japan stock market correlations

ABSTRACT Foreign investors’ transaction volume in the Tokyo Stock Exchange has grown steadily in the past three decades, and Japanese stocks have become a familiar instrument for international diversification. Rebalancing trades in a local national market by foreign institutional investors holding multi-country asset portfolios, often heavily represented by U.S. stocks, amplify the national market’s stock index co-movements with the U.S. This paper examines the extent to which greater participation of foreign investors is associated with increases in the unconditional correlation of daily returns between the U.S. (S&P 500) and Japan (TOPIX). A Gaussian copula marginal regression model is applied to the monthly series of unconditional correlations. We find that the growth in foreign investors’ transaction share of the Tokyo market’s turnover approximately accounts for the rise in U.S.-Japan correlations for 1990–2019. Foreign investors’ trades improve the informational efficiency of local national markets. Increased correlations lead to smaller potential gains from international diversification, however.

Powers Correlation Analysis of Returns with a Non-stationary Zero-Process

Abstract The higher order dynamics of individual stocks is investigated. We show that classical powers correlation analysis can lead to a spurious assessment of the volatility persistence or long memory volatility effects, if the zero return probability is non-constant over time. In other words, classical tools are not able to distinguish between long-run volatility effects, such as IGARCH, and the case where the zero returns are not evenly distributed over time. As a remedy, new diagnostic tools are proposed that are robust to changes in the zero return probability. Since a time-varying zero return probability could potentially be accompanied by a non-constant unconditional variance, we also develop powers correlation analysis that is robust in such a case. In addition, the diagnostic tools we propose offer a rigorous analysis of the short-run volatility effects, while the use of the classical powers correlations lead to doubtful conclusions. Monte Carlo experiments, and the study of the absolute value correlation of daily returns taken from the Chilean financial market and the 1-min returns of Facebook stocks, suggest that the volatility effects are only short-run in many cases.

Diversification measures: Mutual fund family case

This study introduces a portfolio theory motivated approach to measuring mutual fund family-level risk diversification. The average cross-fund correlation in idiosyncratic returns measures diversification of idiosyncratic risk, while the correlation of predicted returns from the multifactor model measures factor risk diversification within a fund family. We document a substantial cross-sectional variation in family-level diversification measured with our new proxies independent of the number of funds and objectives in the family. While number of objectives is a popular yet possibly misleading measure of diversification, there is a link between portfolio theory-based diversification measures and the number of objectives in a family. On average, fund families with more investment objectives are more diversified in terms of both idiosyncratic and factor risks; yet, in large families, more investment objectives are associated with increased diversification of idiosyncratic risk but decreased diversification of factor risk. Fund family diversification improves family performance during market downturns and in large families. However, fund family diversification does not significantly affect absolute or relative family size, except for the number of investment objectives, which has a negative relation to family size.

Potential diversification benefits: A comparative study of Islamic and conventional stock market indexes

The study aims to contribute to the better understanding of potential diversification benefits for US and its major trading partners, namely Canada, Japan, and the UK, across both Islamic and conventional indexes. We applied a Dynamic Conditional Correlations (DCC) model to examine the dynamic correlation and volatility of returns during 2001–2017. The findings put in evidence that, unlike Canadian peers, Japanese indexes exhibit a low dynamic correlation with US indexes, which ultimately suggests diversification opportunities for US-based investors. Understanding volatilities and correlations patterns through international markets would help investors, policymakers, and market participants to take informed decisions, mitigate risks, and anticipate potential spillover effects.

Does prior stock return correlation predict future stock return correlation?

Does prior stock return correlation predict future stock return correlation?

Exploring the time-varying dependence between Bitcoin and the global stock market: Evidence from a TVP-VAR approach

This study examines the return dependence between Bitcoin and major international stock markets from January 1, 2018, to September 30, 2021. Utilizing a time-varying parameter VAR (TVP-VAR) model with stochastic volatility, we analyze the dynamics of the dependence structure while considering market uncertainty indices (UCRY Policy, UCRY Price and VIX) before and after the outbreak of COVID-19 pandemic. Our findings indicate that Bitcoin's role as a safe haven for stock markets has yet to be observed during the post-COVID-19 period. Furthermore, we observe varying impacts of the return correlation between different stock markets and Bitcoin, suggesting an asymmetric dependence. These results contribute to the ongoing discussion regarding Bitcoin's role as a safe haven asset and provide valuable insight for investors and policymakers.