Fantasy baseball Stat Focus: Kipnis' wRC+ shows off offensive value
Robinson Cano has been every bit the first-round pick the entire fantasy community expected him to be back in March. Through 432 plate appearances, he's hitting .299/.382/.519 with 21 homers, 69 RBI, 53 runs and six steals. He has been worth 3.8 WAR according to Fangraphs, and remains the main reason the Yankees are still a part of the playoff race. But while no one is going to knock him from his perch in a season when he's again posting All-World numbers, he hasn't been the best fantasy second baseman in 2013. That honor belongs to Jason Kipnis.
Kipnis showed what he was capable of in his blistering first half of 2012, when he hit .277/.345/.419 with 11 homers, 49 RBI and 20 steals. He fell off a cliff in the second half, showing the fatigue that affects many 25-year-olds in their first full season. We're just a few weeks into the second half of this season, but it appears Kipnis has turned a corner in terms of being able to put together a full season. Through 395 plate appearances, he's hitting .299/.381/.521 with 15 homers, 62 RBI, 57 runs and 21 steals. Clearly, you're just splitting hairs trying to pick between these two, at least when it comes to traditional fantasy stats. There is one advanced metric in which Kipnis has a clear advantage, and that is weighted runs created plus (wRC+).
The stat, admittedly a mouthful even for a supporter of sabermetrics like myself, measures the totality of a hitter's contributions to his team's offense by placing a value on everything a hitter or base runner can do, and crunching it all into one number. Singles carry less weight than doubles, which carry less weight than triples, which carry less weight than homers, and so on. Walks add to the value, while strikeouts detract; ditto for stolen bases and caught stealing. The great thing about wRC+ is that it's league- and park-adjusted, and it also uses a baseline of 100. If a player's wRC+ is 120, he created 20 percent more runs than the average player. If it's 80, he created 20 percent fewer runs than average.
There's a version of the stat that isn't adjusted for league or park, and that's known simply as weighted runs created. It is based on wOBA, which we talked about with regard to Miguel Cabrera earlier this year. As we discussed then, wOBA uses the same principle that says a homer is more valuable than a triple, which is more valuable than a double, and gives us a number that fits into a batting average of OBP context. Given that it applies proper weights to each type of hit, unlike batting average, OBP or slugging percentage, it is a more accurate measure of hitter performance.
Back to our Kipnis-Cano debate. Cano's wRC+ is an excellent 140 thus far this season, good for 21st in the league. Kipnis, however, is tied with Carlos Gonzalez for 11th with a wRC+ of 150. That matches Cano's career high, set last year. In just his second full season in the majors, Kipnis has a great chance to notch a better wRC+ than Cano ever has. The latter may still hold the second baseman championship belt, but Kipnis has a chance to claim it for good in 2014.