Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

It was yet again another day of stronger-than-expected economic data for investors, who took the opportunity to push the broad-based S&P 500 (SNPINDEX:^GSPC) lower on the expectation that the Federal Open Market Committee will take this news as even more reason to begin the tapering of its monthly monetary stimulus.

Two primary reports today pointed to the economy being in better shape than many had projected. First, the Consumer Price Index, a measure of inflation for a similar basket of goods that consumers purchase month to month, was flat in November versus an expected rise of 0.1%. This would signal that inflation is tame on both the business and consumer level, which is great news for consumers looking for an extra reason to spend more this holiday season.

Second, the National Association of Homebuilders index came in with a reading of 58, which was up from 54 last month and higher than economists' expectations. This index is a measure of homebuilder sentiment, and the reading suggests that homebuilders are expecting home prices and sales to flourish in 2014.

Despite this positive news, fear of a somewhat imminent stimulus taper pushed the S&P 500 lower by 5.54 points (-0.31%) to close at 1,781, its fifth day lower in the past six sessions.

Topping the charts and leading all companies higher on the day was KKR Financial (NYSE:KFN) which jumped 30.6% after agreeing to be bought out by (get this...) KKR (NYSE:KKR). The all-stock buyout will net KKR Financial shareholders 0.51 shares of KKR common stock upon closing, but the deal itself is a bit odd given that KKR already manages KKR Financial. The deal, according to parent company KKR, will immediately add assets and boost earnings, which sounds great on paper but isn't passing muster with investors who pushed the parent company down on the day.

Shares of Idenix Pharmaceuticals (NASDAQ:IDIX) plugged higher by 17.8% after the clinical-stage biopharmaceutical company announced that the U.S. Patent and Trademark Office had declared a patent interference between an Idenix patent and one from Gilead Sciences (NASDAQ:GILD). Within the USPTO's designation, Idenix was declared the senior party and Gilead the junior party. According to USPTO procedures, it's up to the junior party (Gilead) to prove that it developed the patent first. Today's action clearly shows that Idenix's intellectual property could wind up being its saving grace, which is good news since it has struggled mightily to develop its hepatitis C therapeutic pipeline.

Finally, consumer robot manufacturer and Roomba developer iRobot (NASDAQ:IRBT), advanced 17.3% after being upgraded to strong buy from market perform by Raymond James. The company also received a price target of $39, a 25% premium to yesterday's close. Raymond James' covering analyst noted that new product introductions, including the latest Roomba model and a robotic mop known as Braava, should boost sales in 2014. I'm still a bit concerned how budget tightening may hurt iRobot's sales to the government, and, as such, am suggesting you tread cautiously for the time being.

Fool contributor Sean Williams has no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen name TMFUltraLong, track every pick he makes under the screen name TrackUltraLong, and check him out on Twitter, where he goes by the handle @TMFUltraLong.

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