"With inflation running at around 1 percent, at this point I think the risk is greater that we should be worried about inflation undershooting our goal and getting inflation back up to 2 percent."

Janet Yellen, chairwoman of US Federal Reserve,

suggesting persistently low inflation poses a more immediate threat to the US economy than rising prices, Reuters reported. In her second public speech since taking the Fed's helm, Yellen was careful not to predict when interest rates would rise from near zero. Instead, she stressed the decision would hinge on healing in the labor market and on how briskly inflation rises toward the Fed's 2 percent goal. Yellen's relatively staid remarks intensified somewhat when asked whether she would let inflation creep above 2 percent to give the economy a bit more support.

"Several parts of the economy are warming up, but housing is the exception … We are still on track for very strong second-quarter growth."

Ryan Sweet, a senior economist at Moody's Analytics,

commenting on the fact that US industrial production rose at a faster-than-expected clip in March, the latest sign the economy was gaining momentum, Reuters reported. Groundbreaking for new homes also increased but remained well below the post-recession peak hit in November, signaling the drag the housing market is placing on the economy. Output at the nation's factories, mines and utilities rose 0.7 percent last month after an upwardly revised gain of 1.2 percent in February, the Federal Reserve said Wednesday. The increase in industrial production beat economists' expectations for a 0.5 percent gain.

"It's an average quarter from a great company … It's the same old story. Paid clicks were a little lighter than people might have hoped, CPC declines were a little higher than people would have liked, expenses continued to rise."

Colin Gillis, an analyst with BGC Partners,

commenting on Google Inc's lower-than-expected first-quarter revenue, Reuters reported. The number of "paid clicks" by consumers on Google's ads increased by 26 percent in the first quarter, disappointing some analysts who had hoped for stronger volume growth. And the average "cost per click" (CPC) declined 9 percent, extending a downward trend as mobile advertising make up a bigger slice of its business.