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        What Is the FanGraphs Library, and How Do I Use It?

        by Piper Slowinski
        January 26, 2011

        After Dave Cameron’s introduction yesterday, I wanted to take a brief minute to explain the purpose and goal of the Library for those that haven’t seen it before. And before I begin, thanks to everyone for the kind words yesterday about the Library.

        The Saber Library was initially created around a year ago, in response to some criticism we’d received at DRaysBay. Many (most) of our columns there deal with advanced stats, like the work done here on FanGraphs, yet many readers were having a tough time accessing the information and learning about sabermetrics. We’d tried running a saber primer or two, yet those could never be comprehensive enough to cover everything that needed to be said. Readers wanted to learn, but didn’t have a place to go to do so.

        And so, being naive and stupid, I decided to spend the time putting together a comprehensive learning resource where saber newbies could learn practical knowledge about the statistics and concepts that undergird sabermetrics. It was an ambitious project, but I received help from a couple of my fellow writers at DRaysBay and input from living legend Graham MacAree. I made the pages easily linkable, so writers wouldn’t need to re-explain a statistic every time they used it in an article, but could link to the Library and direct their readers there for more information (like, say, wOBA).

        FanGraphs has long needed an updated glossary, so moving the Library here was a no-brainer. I made a number of changes when moving it over – updating content, adding percentile charts, and incorporating more content from elsewhere in the saber-sphere – but its general purpose is still the same: the FanGraphs Library is meant to be used as a learning tool. I provide a concise description of every statistic, document the most important facts to know about each stat, and link to resources to expand your knowledge even further. I hope to continue expanding the Library in the future, and to update pages continuously as need be.

        Some links may have gone on the fritz as we transferred everything, but all old links to the Library should still work. The old saberlibrary.com address is now being redirected to the new site, so if you are a writer and want to continue (or start) linking to the Library in your articles, you can still use our old URLs to make it easier for you. I think they’re pretty intuitive, but you can decide for yourself:

        wOBA
        FIP
        UZR
        WAR

        You can access the FanGraphs Library by clicking on the “Glossary” button above. When you arrive at the Library main page, you’ll see the biggest new feature of the site: a blog! I’ll be writing content over at the FanGraphs Library page, focusing primarily on saber education. I plan to highlight work done around the saber-sphere (so pass along any links if you find something good), while also writing original pieces geared toward helping people understand sabermetrics better. It’s a new space and I want the content to best help you readers, so please send me feedback along the way.

        In short, if you want to learn about sabermetrics, make your articles more accessible for new readers, or teach a friend why batting average isn’t the be-all-end-all, come check out the FanGraphs Library. No Dewey Decimal system required.





        Statistic Percentile Charts
         
        Heat Maps: What They Show, and Mistakes to Avoid

        Piper was the editor-in-chief of DRaysBay and the keeper of the FanGraphs Library.

        7 Comments
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        matt
        14 years ago

        What happened to the online course that was offered offsite?

        -1
        Piper Slowinski
        14 years ago
        Reply to  matt

        That’s offline at the moment while their site goes through some restructuring. I hope to bring it back eventually, new and improved. No time table on that, though…really depends on the course site.

        0
        Eric
        14 years ago

        I just want to say that adding the percentiles is a great thing to have. I think I have at least a basic understanding of a lot of the stats but sometimes have a problem hearing a number and placing it in context, and this makes my life a whooole lot easier. Love the library, thanks guys for all your great work.

        0
        Steven
        14 years ago

        This is a thing of beauty. For a fan who doesn’t have the time to invest otherwise, it’s a godsend. THANK YOU.

        0
        bcp33bosox
        14 years ago

        This is *AWESOME!*

        Steve (and FanGraphs) thank you so much for doing this, I really look forward to using the library and learning more about sabermetrics!

        0
        studes
        13 years ago

        Question: how is RS (Run Support) calculated? Is it based on the innings in which the pitcher pitched? How does it account for partial innings?

        I’m not sure if this is the place to ask this. If not, sorry.

        0
        GK
        10 years ago

        Hi,

        It looks like I am years late to this party, but now that I am here, I thought I should let you know that none of the links work for wOBA, FIP, UZR or WAR. It appears that saberlibrary.com is no longer accessible, which would make sense if the site is no longer used and everything has been ported from that site.

        You may want to take some time to update the links as well as any other information provided on this page, as this is one of the places that is suggested as a starting point for people new to saber metrics. I am sure the info is still available somewhere, but it would be a big help if the links provided here actually worked.

        1
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