economies of the United States and China just by using security prices.
Subsequent research such as those of Lo and MacKinlay (1999), questioned strict efficiency especially in
developing economies, their study suggests that short term return predictability and behavioural anomalies do
exist and can be used to achieve superior return.
Whenever an analyst wants to study the performance of any market, the U.S. market which is characterized by
significant liquidity and extreme institutional participation is used as the benchmark, especially regarding market
efficiency (Malkiel, 2003; French, 2008), in an American environment that significantly support equity markets
through innovation, capital and financial stability (Kamel, Beainy, & Bteish, 2025).
On the other end, in the Chinese equity market, state influence is a norm, and regulatory intervention is repetitive,
which may result in additional inefficiency and higher volatility, these claims are supported by results of multiple
scholars (Girardin & Liu, 2019; Chen et al., 2021), in addition Morck, Yeung, and Yu (2000) demonstrate
stronger co-movement among Chinese stocks, attributed to herding Behavior (investors move together) and
limited information transparency, even with the current modernization and the global index inclusion, recent
studies and empirical analysis find that Chinese equities remain, more than anywhere else in the world, sensitive
to policy and liquidity shocks (Li & Giles, 2022; Zhang, 2023).
Beyond the simply return analysis, empirical finance literature nearly always use risk adjusted metrics to evaluate
efficiency, such as the Sharpe ratio (Sharpe, 1966) and Sortino ratio (Sortino & Van der Meer, 1991) that serve
as a worldwide accepted tool to be able to compare excess return relative to volatility and downside risk. While
other ratios such as the Calmar ratio (Young, 1991) provides an additional perspective on capital efficiency
relative to drawdowns. The significance of these ratios are most apparent in emerging markets where they reveal
significant deviations from developed markets, and this can be justified because of the weak governance,
illiquidity and behavioural biases that are often the characteristics of an emerging economy (Bekaert & Harvey,
2017).
Past studies that focus on comparing the U.S and Chinese markets show mixed findings, as Wang and Chen
(2020) highlight that U.S. equities offer lower volatility clustering and downside tails, while corrections in their
Chinese counterparts are sharper and riskier. Huang, Yang, and Zhou (2021) support these findings, and they
argue that although Chinese equities demonstrate positive skewness, their high kurtosis and tail dependence
reduce long-term risk-adjusted returns. Regarding the correlation between the markets, recent research (Tang et
al., 2022) indicates a currently moderate, yet increasing correlation between U.s and Chinese equities, this was
particularly the case during the Covid-19 global stress period.
Reference the above previous findings, the literature supports three expectations, the first being that U.S equities
should outperform their Chinese counterpart, especially on a risk adjusted basis, the second is that Chinese
equities should have a much higher volatility in addition to heavier tail distribution (more risk of a major
downward movement), and the third is that diversification benefits of investing in both Chinese and American
equities are expected to be significantly limited. Those three assumptions are examined as hypotheses, using
daily data, traditional and modern econometric methods and Python-based analytics, with the goal to link
between the academic theories with the practical and actual performance of the largest firms within the two
countries.
METHODOLOGY
The Goal of this study is to evaluate and compare the financial performance, risk and the inter-market correlation
between major U.S and Chinese Equities. To succeed through this quantitative, empirical based and comparative
design, daily data using a 15-year time horizon were used, and both broad market exchange traded funds (ETFs)
and specific mega cap firms were studied in both economies. The research design aims to provide a four-
dimensional view of the market, through descriptive performance measures such as return and volatility, risk
adjusted efficiency metrics such as Sharpe, correlation analysis through a heat map and capital asset pricing
relationships.