Among the most egregious, in his opinion, was the need for the number to be placed into a team context. Recall that the BRC formula accurately predicts a team’s runs to within 5 percent, and the adjustments for statistics available in a given season usually moves the estimate to well within 1 percent. James used the following examples to illustrate what he asserts was one of the shortcomings: Player A and B play on Team 1. Each has 400 AB + BB, 150 TB, and 150 H + BB, for BRC = (150)(150) / 400 = 56.25, or a total for the two of them of 112.25, which matches the sum of their accomplishments 800|300|300 for BRC = (300)(300) / 800 = 112.5. However, consider Player C and Player D on Team 2. Player C has 400 AB + BB, 100 TB, and 100 H + BB, or BRC = (100)(100) / 400 = 25. Player D has 400 AB + BB, 200 TB, and 200 H + BB, with BRC = (200)(200) / 400 = 100. Their total BRC as a sum of the individuals is 125, but their aggregate totals match the players from Team 1, 800|300|300 and BRC = 112.5.
What do You think about Understanding Sabermetrics?
