Investors have entered 2011 eager to embrace riskier, higher-yielding assets, but happy to dump them at the first whiff of anything negative.
It portends rocky but potentially bullish market sentiment in the coming week with a new US earnings season getting underway and signs that the world's biggest economy is mending.
Positive US economic news - including an improvement in the labour market, typically seen as lagging other indicators of growth - has generally lifted stocks over the past week, particularly on bourses in developed, trade-oriented economies.
Japan's Nikkei gained more than three percent in the first four trading days of the year, for example, compared with an annual loss of three percent last year.
Bond yields have also continued to rise, as they did for much of the fourth quarter, with prices falling as investors seek better-yielding assets. "We have entered the year where consensus expectation has shifted upwards in terms of global growth," said Tristan Hanson, strategy manager at wealth manager Ashburton in Jersey. "That has manifested itself in bond yields rising."
For investors, the big issue will be whether they are correctly positioned for what could turn out to be better global growth than expected. Take, for example, the dollar. The US currency has risen more against a basket of major competitors over the past week than all but five weeks in the last two years.
This has come on the back of the better US economic outlook. But a number of investors, including those in dollar-based commodities, have got used over the past few years to a rising dollar being part of the risk-aversion trade.
The rising dollar has thus been part of the fall in the Reuters Jefferies CRB index in the past week, although good economic news should normally lift most commodities.
A part of the fall may be related to concerns that new US growth might mitigate the need for the Federal Reserve's liquidity-producing quantitative easing (QE) programme, a move that boosted commodities sharply.
But a growing economy should nonetheless create demand for commodities.
"If you see the oil price coming off a lot based on a dollar that is rising because of stronger US economic growth, that would be a buying opportunity," Hanson said. Another new factor for investors to consider is the relative underperformance of emerging markets stocks, the golden assets of 2009 and 2010.