The calculation of the WAR statistic is relatively complex, but the idea behind the statistic is simple. How much is a player worth above a replacement quality player? (A replacement player is generally considered to be a high quality minor league player or perhaps a bench player).
The statistic is normalized around 0. If a player's WAR value is > 0, the player is performing better than a replacement player. If the player is performing < 0, a team would be better off replacing that player with a replacement player.
I love this statistic because of what it represents. So much decision making in our lives comes down to a simple judgement of "Can I do better?". For example:
- Hiring Employees: "Sally is a good candidate, should we hire her or keep on interviewing more candidates?
- Firing Employees: "Joe is a bad performer, but still accomplishes a lot of stuff. Should we keep him?"
- Job: "Company A has a ton of problems, should I stay or go?"
- Job offers: "Company X just offered me Y thousand a year. Should I take this offer?"
- Dating: "Suzy is a great gal, but is she the right one for me?"