U.S. bond yields edged lower on Monday, with the benchmark 10-year yield falling to 2.06 percent and the two-year yield falling to 0.60 percent from above 0.65 percent earlier in the day.
Yellen will address the Senate Banking, Housing and Urban Affairs Committee at 10 a.m. on Tuesday and the House Financial Services Committee on Wednesday.
This congressional testimony will be particularly of interest because the Federal Open Market Committee meeting minutes released last week indicated a more dovish policy than the official Fed statement.
"Janet Yellen will walk us away from dovish minutes and something more data-dependent," said Art Hogan, chief market strategist at Wunderlich Securities. He thinks a rate hike will come in June.
"We need to get away from zero interest rates," he said.
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Economic reports continue mixed, with Monday showing that existing home sales dropped 4.9 percent in January, their lowest level in nine months.
Investors will get more insight into the housing market with the S&P Case-Shiller Home Price Index at 9 a.m. on Tuesday. Mortgage applications and new home sales come on Wednesday.
Consumer confidence comes out at 10 a.m. on Tuesday.
JJ Kinahan, chief derivatives strategist at TD Ameritrade, is watching the housing data and consumer indicators to see how last month's strong jobs report is playing out in the U.S. economy.
After last week's upbeat showing by Nordstrom and Wal-Mart, which represent two tiers of the consumer, Kinahan said, "It'd be great to see the same sort of numbers out of Macy's and Kohl's."
Macy's reports quarterly earnings before the bell on Tuesday, while Kohl's reports early on Thursday.
Both Wal-Mart and Nordstrom posted one-year earnings per share estimates that show signs of improvement, according to The Earnings Scout research.
However, for most sectors of the market, The Earnings Scout CEO Nick Raich said that "expectations are very, very weak."
"We think the worst is behind us, (so we are) modestly bearish on stock. We don't think the markets have fully factored in the slowdown in the first half of 2015," he said. "We're not OK paying a higher price-earnings ratio as earnings expectations continue to deteriorate."
U.S. stocks pulled back from Friday's records to close narrowly mixed on Monday.
The Dow Jones industrial average closed down 23.6 points to 18,116.84, weighed by a 2 percent decline in Boeing. Goldman Sachs downgraded the airplane manufacturer to "sell" from "neutral," saying the firm is the most exposed in the industry to aircraft demand risk.
The S&P 500 closed down at 2,109.66, slightly off its all-time high set on Friday.
The Nasdaq was the only major index to close in the black, up 5.01 points at 4,960.97.
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Crude oil settled below $50 a barrel, while Brent fell to dip below $59 a barrel. Oil spiked briefly on a Financial Times report that the recent declines could trigger an OPEC emergency meeting.
The Greece saga continued to drag out as the government said it would submit the list of its reforms to the Eurogroup on Tuesday, rather than Monday, as the Eurogroup had requested.
The slight delay did not disturb stocks or analysts on Monday as the four-month bailout extension agreed to on Friday would likely hold.
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"Greece may take a backseat for the next few months but four months from now we're going to talk about all these things," said Peter Cardillo, chief market economist at Rockwell Global Capital.