What are China’s quantitative trading funds, and why are they so controversial?

For years, quantitative trading was the undisputed darling of China’s stock market, using sophisticated algorithms and artificial intelligence to deliver eye-popping returns and grow into one of the most powerful drivers of trading volume and liquidity, even as traditional, discretionary stock-pickers struggled to keep pace. Yet that rise has also stirred growing controversy, particularly during periods of market turmoil, when critics argue that computer-driven strategies exacerbated volatility...