JPMorgan’s China Calls Show Market Timing Is Tough

Predicting the returns of Chinese technology stocks is harder than ever in an age of shifting government policy, rising interest rates and cooling economies.

Take JPMorgan Chase & Co.’s Alex Yao. He downgraded 28 Chinese internet stocks in March, calling the industry “uninvestable” — right before an epic rally. He then shifted to upgrade the sector in mid-May and, while indexes are higher since then, the biggest company, Tencent Holdings Ltd., is down nearly 20%. Alibaba Group Holding Ltd. is a hair’s breadth away from wiping out all the gains since Yao upgraded the stock.