Overrated/Underrated: Tebow doesn't offer flash but consistency

Tuesday was an interesting day on Wall Street. American Airlines filed for bankruptcy protection, while Groupon continued its post-IPO slide. Savvy investors could have seen both coming; the former was a legacy airline getting eaten up by leaner, more modern options while the latter, well, let's just say that I'd need a lot more writing space to get into the problems there.

The point is, there is value everywhere. In the same way that you can look at equities or different products in a supermarket to find value, you can in the fantasy football world as well. All you have to do is strip away the names from the players and look at their performances. That's what we do in this column.

Tim Tebow, QB, Broncos (64 percent owned)

We all know Tebow is the best QB in the league, but for some reason, fantasy owners don't seem to be acknowledging that fact. Fools. All kidding aside, owning Tebow is like playing an elite running back in your QB slot. He is the sixth most efficient rusher in the league, which more than makes up for his dismal passing numbers. Tebow has put up 13-plus every week so far and has scored 16-plus in all but one game. In fact, Tebow, surprisingly, is one of the most consistent QBs in the league since his first start in Denver. He's a top 10 fantasy QB, despite throwing the ball like a drunk Tyler Palko with a rotator cuff injury.

Johnny Knox, WR, Bears (31 percent owned)

Knox is the Bears true No. 1 receiver, and against logic, the Jay Cutler injury might actually help him. Cutler and college teammate Earl Bennett had quite the rapport, but Knox is the superior deep threat. Knox is the most targeted receiver on the Bears with 53 and is the most efficient receiver in the league with at least 20 receptions on a per play basis. Knox has 36 fantasy points in his last two games and was targeted a team-high 10 times on Sunday from Caleb Hanie. Of course, if the Bears were smart, they'd just hand the ball off 50 times and not let Hanie throw at all, but ...

Donald Brown, RB, Colts (12 percent owned)

To start the season, Brown was third on the Colts depth chart behind notable running studs Delone Carter and Joseph Addai. After the inevitable Addai injury, however, the Connecticut product has strutted his stuff, providing an oasis of competency in a desert of terrible. Brown is the most efficient running back on the Colts, adding five points above expectation so far this season. He has 54 fantasy points over his last six games, including a solid 16-point performance against Carolina on Sunday.

Dez Bryant, WR, Cowboys (99 percent owned)

You would think that Bryant would have greatly benefited from the Miles Austin injury, but he hasn't. Instead, journeyman Laurent Robinson has stepped up in Austin's place and gotten the majority of the production. Bryant is still second on the team in targets, but only eight ahead of Robinson, who has started only half of the games. Even worse, his 56 percent catch rate pales in comparison to Robinson's 64 percent. Bryant has scored more than 10 points in just half of his games and has yet to put up a 20-point game. That would be unacceptable from Antonio Bryant, much less Dez.

Rashard Mendenhall, RB, Steelers (99 percent owned)

Much like those of us long on JMBA, Rashard Mendenhall owners have been sorely disappointed this year. After back-to-back weeks above 10 points however, there seemed to be hope. Unfortunately, Mendenhall produced his seventh game under 10 points on Sunday night in what seemed like a great matchup against Kansas City and the fighting Palkos, frustrating those who started him again beyond belief. Further, Mendenhall has not even been the most efficient running back on the Steelers! Isaac Redman has a beastly 52.24 percent success rate, much better than Mendenhall's 36.60 percent. Someone get Kevin Colbert on the phone!

Greg Olsen, TE, Panthers (75 percent owned)

It's feast or famine with Olsen. And like that vegetarian friend we all have who swears by Tofurkey, the feast isn't so tasty. Olsen has scored 10-plus just three times this year, and has never broken 15. Add in four games with less than three points -- including each of his last three contests -- and you've got dead weight on your fantasy roster. Olsen may be second on the Panthers in targets, but has a mediocre 54 percent catch rate, well below league average for a tight end. Dustin Keller, Fred Davis and Jake Ballard are all better options.

Nik Bonaddio is the CEO of numberFire, a sports analytics platform that provides algorithmic modeling for sports. You can follow him @numberfire. Keith Goldner is the Chief Analyst at numberFire. You can follow him @drivebyfootball. And be sure to visit numberFire on Facebook.