NEW YORK - Wall Street and stock market investors in general aren't feeling much love for Ben S. Bernanke lately.

Stocks plunged Tuesday after the Federal Reserve chairman and his fellow Fed policymakers cut interest rates one-quarter of a percentage point, disappointing those hoping for a half-point reduction.

A surprise announcement a day later by the Fed and four other central banks of a plan to increase the supply of dollars in Europe and the United States has drawn catcalls from some who say it will not do much to defuse the global credit crisis.

By week's end, the Dow Jones industrial average had fallen 3.1 percent from where it was just before Tuesday's Fed rate decision was released. Such a downdraft underscores the growing anxiety over credit woes and how it might spill into everything from deal-making to corporate earnings in 2008.

"Investors are skittish," Arthur Hogan, chief market analyst at Jefferies & Co. Inc., said. "If you look at the magnitude of the headwinds hitting the market and the brand of medicine we're getting from the Fed, it is hard to say we've got the right dosage."

The nation's big investment banks and brokerages are on the front lines of the credit crisis and have taken some pretty big fiscal hits stemming from the collapse of the subprime-mortgage industry. That is why Wall Street is paying close attention to their quarterly earnings reports.

Lehman Bros. Holdings Inc. beat expectations Thursday - but investors were rattled after the No. 4 securities firm said its fixed-income portfolio suffered $3.5 billion in losses.

Morgan Stanley already has warned that it expects to take a $3.7 billion write-down when it reports fourth-quarter results Wednesday, while the Bear Stearns Cos. Inc. expects a $1.2 billion charge in its report Thursday. The Goldman Sachs Group Inc., the largest investment bank, is expected to post no net credit-related losses Tuesday because of hedging activities.

Also weighing on investors is the future of "structured investment vehicles," or SIVs, which are investment funds created by banks. The funds borrow short-term money and invest it at a higher rate in mortgage, bank and credit card debt.

Citigroup Inc. said it planned to assume control of the seven SIVs it advises to help them repay lenders. The viability of an SIV hinges on its ability to continue borrowing short-term money, and that has been disrupted by the credit freeze. What's more, massive losses from these investments could be yet another assault on the financial industry's earnings power.

Erin Callan, Lehman's chief financial officer, said, "November was absolutely the worst month ever on record for the fixed-income markets." It is a powerful statement considering the summer's market turmoil knocked the Dow Jones industrial average down 10 percent before recovering.

Though top bank executives are hesitant to say the worst is over, there are some positive signs banks can weather the crisis into 2008. For instance, Lehman was able to offset fixed-income losses thanks to strength in its merger-and-acquisition advisory business, and there is hope others can do the same.

"The process we're going through, though painful, is necessary," Hogan said. "The banks have to work through all the bad if we're ever going to move forward."