Statistics play an important role in summarizing baseball performance and evaluating players in the sport.
Since the flow of a baseball game has natural breaks to it, and normally players act individually rather than performing in clusters, the sport lends itself to easy record-keeping and statistics. Statistics have been kept for professional baseball since the creation of the National League and American League, now part of Major League Baseball.
In baseball statistics, earned run average (ERA) is the mean of earned runs given up by a pitcher per nine innings pitched (i.e. the traditional length of a game). It is determined by dividing the number of earned runs allowed by the number of innings pitched and multiplying by nine. Runs resulting from defensive errors (including pitchers' defensive errors) are recorded as unearned runs and are not used to determine ERA.
Zachary Ben Hample (born September 14, 1977, son of Stoo Hample and Naomi Cohen) is an American sports writer and Major League baseball collector. He is best known for having caught more than 7,000 baseballs in the stands at Major League stadiums.
The "juiced ball" theory suggested that the baseballs used in Major League Baseball (MLB) during the 1990s and early 2000s were altered in order to increase scoring.
It was claimed that a "juiced" ball bounces off the bat at a higher speed. Johnny Oates observed hits being made off pitches that should not have been elevated.