Expectant eyes from around the world will be on Ben Bernanke Friday, looking for assurances that the US economy is solid or, if not, that his Federal Reserve is ready to invest more to stimulate growth. Markets have been on edge for weeks over whether the Fed chairman will act on the sluggish economy, making his keynote speech the main event at the Fed's annual international central banking symposium in Jackson Hole, Wyoming this weekend. But with data pointing sideways, and vital determinants of the current economic situation out of his control, few are agreed on just what the taciturn, scholarly US central bank chief should or indeed could do. Bernanke used the Jackson Hole venue the past two years to let markets and policymakers know what is on his mind. In 2010, he moved the markets with his signal of "QE2" -- a second $600 billion quantitative easing program aimed at pushing down long-term interest rates. In 2011, he went in the other direction, telling the White House and Congress not to expect the Fed to do their job, but to take policy actions themselves to strengthen growth. The record of sluggish expansion this year, 2.0 percent growth in the first quarter slowing to 1.7 percent in the second, is evidence of how that message fell flat. But to the policymakers of the Fed's Federal Open Market Committee, led by Bernanke, that is not necessarily enough to merit QE3. The FOMC has to decide whether the data of the past three months, with no clear break between positive and negative signals, demands their policy response. "Many investors believe -- hope -- Bernanke will again use this opportunity to signal new stimulus," said economist Lindsey Piegza at FTN Financial. The signals from the economy are decidedly mixed: job creation, one of Bernanke's central focuses, has been soft, with unemployment still above 8.0 percent. Manufacturing growth, which appeared to be strengthening at the beginning of the year, now seems to have slowed though not stalled. The housing sector, one of the biggest black holes in the economy since 2006, has shown signs of bottoming out, a response in part to the Fed's ultra-low interest rates. Consumer spending is picking up as well, and banks are lending a little bit more, both good signs for the economy. "Growth is neither strong enough for Mr Bernanke... to take any additional easing off the table, but it is hardly weak enough to force him to announce new actions," said Joel Naroff of Naroff Economic Advisors. What is different now is that Europe has slipped back toward recession and China's growth has sharply decelerated. That means that neither can be expected to spend on goods from reinvigorated US industries that have been important to getting the economy from the recession to the modest strength it shows now. Bernanke and the FOMC have consistently maintained that they can adopt more stimulus if the economy needs it. "There is scope for further action by the Federal Reserve to ease financial conditions and strengthen the recovery," Bernanke told a lawmaker last week. But, he added: "The committee will closely monitor incoming information on economic and financial market developments and will provide additional accommodation as needed to promote a stronger economic recovery." Bernanke also needs a strong consensus of the members of the FOMC before undertaking policy changes. The committee, which holds its next policy meeting on September 12-13, remains divided. More are leaning toward stimulus, but some say it is still not merited and could lead to trouble. "Certainly our current expansion is not on the track we would wish," said Dennis Lockhart, head of the Fed's Atlanta district and an FOMC member. But he cautioned: "There is a risk to monetary policy being employed too aggressively and without effect to address economic problems that can be resolved only by fiscal reforms that involve making tough choices about the allocation of public resources." Economists were split on what Bernanke might say and what could come out of the subsequent FOMC meeting. Some doubted any fresh action barring a sharper downturn in Europe, saying that the Fed would likely wait for the European Central Bank to move first. But after seeing the tepid data in Wednesday's Beige Book, the regional economy survey the Fed uses to inform its policy-making, Nigel Gault at IHS Global Insight said the Fed will act. "The outlook is worse than the Federal Reserve's June projections, and as a result we expect to see another round of quantitative easing from the Fed, when it meets in September," he said.