Oftentimes, as a proponent of advanced stats in baseball, I throw out my favorite stats in discussions and articles. For some fans, wOBA, wRC+, SIERA, and WAR have no value, especially compared to traditional numbers like ERA, batting average, OBP, SLG, and OPS.
What Makes wRC+ Valuable?
The best all-encompassing hitting stat, wRC+ (weight runs created plus) gives a player credit for how valuable each outcome is and adjusts for park and league factors. Using wRC+, 100 is the league average, and a point higher or lower is one percent better than the league average. For example, a 115 wRC+ is 15 percent more valuable than the league average hitter on a rate basis. This is what makes wRC+ so easy to use and understand, all it takes is a quick glance to understand the value of a hitter.
How is wRC+ Calculated?
The basis of wRC+ comes from wOBA (weight on-base average), so let us first understand how wOBA is calculated, and why it exists. wOBA is scaled to OBP (on-base percentage) but gives the correct run value to each type of hit. The weights for wOBA fluctuate each year, but a home run is always more valuable than a triple, which is more valuable than a double, and so on. OPS (on-base-plus slugging) tries to do the same, but slugging has its flaws, as a double is not twice as valuable as a single, and a home run is not twice as valuable as a double. Also, OBP is more valuable than SLG in pure run value, so simply adding these statistics gives an incomplete or inaccurate view.
wOBA is used in the calculation for wRAA (weighted runs above average), which is simply a player’s wOBA compared to the league average wOBA, then multiplied by plate appearances to turn it into a cumulative stat. wRC+ is wRAA, but adjusted based on park factors and league factors. For example, more http://online-pharmacy.org runs are scored at Coors Field than Oracle Park, and the average wOBA at these parks are also very different, so wRC+’s park adjustment makes up for this.
2021 wRC+ Leaders
Since wRC+ is a nearly all-encompassing offensive (not including baserunning) stat, the leaders are normally who you would expect them to be. So far, this year’s leader is Vladimir Guerrero Jr., who sports a 167 wRC+. He has been fading quickly, as Bryce Harper (163) and Shohei Ohtani (162) have begun to catch up. Rounding out the top five are Fernando Tatis Jr. and Jesse Winker. Generally speaking, the best hitters in wRC+ are the guys you would expect, but players who get on base a lot have a slight advantage.
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