Updated on December 8 at 8:35 a.m. ET

Chinese stocks closed up Friday after a week of upheaval that roiled global markets from Tokyo to New York in the first days of the trading year. Markets in Europe and the U.S. were sharply higher, as well, on the back of extremely strong job growth in December.

The gains in China were attributed to three steps by the government: First, the suspension of a circuit-breaker mechanism that kicked in when stocks dropped precipitously, as they did on Thursday. But that mechanism, which was intended to lessen volatility, instead served to spook markets around the world.

Next, the People’s Bank of China, the country’s central bank, set a higher yuan fix for the first time in nine trading days. On Thursday, the central bank set the yuan at its lowest level since March 2011. A cheaper yuan would boost Chinese exports, but would raise fears the Chinese economy is doing worse than believed. Thursday’s decision also sparked fears of a region-wide rush to devalue currencies.

Third, Bloomberg reported, citing people familiar with the matter, that state-controlled funds purchased Chinese stocks, focusing on financial shares and on equities with large weightings in benchmark indexes.

In apparent response, markets closed up 2 percent. European stocks also performed better after China’s decision, while in the U.S., markets surged after the latest jobs report showed strong job growth in December. The economy added 292,000 jobs last month, and the jobless rate stayed at 5 percent. Many economists had estimated the economy would add 200,000 jobs in December.

Still, the volatility in Chinese markets spread around the world this week, and, as my colleague Joe Pinkser pointed out the advice from the media generally boiled down to two words—don’t panic—but some of the fears affecting markets are steeped in conflicting signals from Chinese policymakers, as well as general worries about the health of the slowing Chinese—as well as the global—economy.

Writing in The Wall Street Journal, Andrew Browne pointed to the “almost comical ineptitude” on the part of Chinese policymakers. He added:

The central bank is clearly not on the same page as the securities regulator. Its surprise decision to steer the yuan sharply lower this week added to panic in the equity markets, where investors took the move to mean that financial authorities are getting desperate about the state of the economy.

Part of the problem, it seems, is a policy-making bottleneck. Mr. Xi has reversed a collective-type leadership process inherited from Mr. Deng and concentrated decision-making authority in his own hands. …

As a consequence, Premier Li Keqiang ’s job has shrunk. His immediate predecessors ran the economy; he doesn’t enjoy the same autonomy. If things go seriously wrong, though, he might end up as a convenient scapegoat. Other highly competent economic leaders look less like decision makers and more like cheerleaders for policy concocted above their heads.

Bloomberg points out that Friday’s reversal on the circuit-breaker is lending weight to the investors’ sentiment that Chinese authorities are “improvising— and improvising poorly—they try to stabilize markets and shore up the economy.”

“They are changing the rules all the time now,” Maarten-Jan Bakkum, a senior emerging-markets strategist at NN Investment Partners in The Hague, told Bloomberg. “The risks seem to have increased.”

Mark Mobius, chairman of the emerging-markets group at Franklin Templeton Investments, wrote in a blog post Thursday:

Clearly, many investors are worried right now. As we see it, there is no question that China should continue to have strong growth this year, but one might say China is facing a bit of a conundrum. On the one hand, the government wants stability, but on the other, it also is striving toward more openness. That means we could see more volatility in China’s market this year as these conflicting forces play out.

Still, he pointed out: “That said, we are not terribly concerned about growth in China, nor its long-term investment prospects. … The fundamentals in China are still excellent, in our view. It is one of the fastest-growing economies in the world even if the growth rate has decelerated.”