A Brief History on Sabermetrics Part I (Hitting)

By Simon Stracher

(NOTE: This is not all of the advanced stats we use in the blog and future posts will explain more).

After getting some responses from viewers that they did not now the stats I was using, I took it upon myself to give the definitions on Sabermetric terms and what Sabermetrics really means. So, without further ado, A Brief History on Sabermetrics.

Hitting Stats:

1. OPS (On-base plus slugging)- On-base plus slugging sounds like what it is: the sum of a player's on-base percentage and slugging percentage. Many "saberists" do not like this stat because it does not weigh on-base percentage more than slugging, even though on-base has been proven to be twice as effective. Nevertheless, it is a good and easy stat to measure a hitter's contact, patience and power. This stat is much more common than others on the list.

Context: (from www.fangraphs.com)-2010 OPS Values

2. OPS+ (On-base plus slugging plus)- While not as well known as OPS, OPS+ is a much more effective tool to measure a players performance. It adjusts small variables such as park effect and the league in which a player plays in. 100 is league average, so therefore each point up or down is one percentage point above or below league average. It is still not entirely effective, because it weighs on-base percentage and and slugging percentage the same.

Context: Miguel Cabrera posted a 179 OPS+ last season (one of the highest) while Cesar Izturis posted an OPS+ of 50 last season (one of the lowest).

3. wOBA (Weighted on-base percentage)- Who do you think is a more effective hitter: Ichiro hitting .360 with the majority of his hits being singles, or Albert Pujols hitting .320 with the majority of his hits being extra base-hits. The answer is unequivocally Pujols, but according to batting average it is Ichiro. The simple fact is that not all hits are created equal. wOBA, unlike OPS and OPS+, weighs OBP more in its formula and is one of the most useful statistics out there today. It combines patience, power and contact, and weighs the most important ones the most, so we can truly see who are the great hitters in today's game.

Context: (from www.fangraphs.com)- wOBA is put on the same scale as OBP, so any score that would be a great OBP is also a great wOBA. League-average is typically around .330, although it varies from year to year.

2010 Values

4. wRAA (Weighted Runs Above Average)- wRAA is based off wOBA, and attempts to calculate the number of runs a player calculates for his team each season. Zero is league-average, so a positive wRAA shows above-average performance, while a negative wRAA shows below-average performance. This is a "counting statistic" (like RBIs) so players gain more runs the more they play. Also, wRAA is league-adjusted, so it is easy to compare players from different leagues and even from different eras.

Context: (from www.fangraphs.com)

2010 wRAA Values

5. wRC (Weighted Runs Created)- wRC is a stat that attempts to measure how many runs a player is worth to his team a year (similar to wRAA). It is not my favorite statistic, but helps make my favorite statistic which is coming up next. Also, if wRC and wRAA sound the very similar, don't worry, you’re not going insane. The stats are very alike – they’re both based off wOBA and attempt to show offensive ability in runs – but wRAA is scaled with zero as league average, while wRC is not. For that reason, if you want to see offensive ability in runs, use wRAA.

Context: (from www.fangraphs.com)

2010 wRC Values

6. wRC+ (Weighted Runs Created Plus)- In my opinion, if you want to be judging a player by his offensive performance only, and you had to pick one statistic, this would be the one I would pick. It is scaled to 100, like OPS+, and is based off wOBA, unlike OPS+, which makes it much more accurate. It measures all of the same things that wOBA does and on the correct weight, but is much easier to use because of how league average is 100 and always 100. Also, wRC+ is park and league adjusted, so you can compare players from different leagues, parks or even decades.

Context: (from www.fangraphs.com)

2010 wRC+ Values

7. ISO (Isolated Power)- ISO is the measure of a players power, or how good he is at hitting for extra bases. It is a relatively simple formula: SLG%-BA, which removes all of the singles that are accounted for in slugging percentage. I like this stat because it shows a hitter's true power and what you can expect from him in upcoming seasons (like if his doubles start becoming home-runs). Also, in order to project future ISO numbers, you should have a sample size of at least 600 PAs. If Brett Gardner has a .550 ISO after 50 PAs, don't take it too seriously.

Context: (from www.fangraphs.com)

2010 ISO Values

I'm sorry I didn't finish all of the hitting statistics, but I will post the rest of them in a day or two.