Supposing that all four runs were earned runs and it is a nine inning game, the ERA is 4.5... Earned runs divided by innings pitched multiplied by the the total innings of a standard game (4/8 * 9 = 4.5)
ERA means Earned Run Average. It is a statistic used for pitchers to calculate how many earned runs the pitcher allows on average over 9 innings (27 outs) pitched
ERA is based on 9 innings pitched. When you see a pitcher with a 4.94 ERA that means for every 9 innings pitched, he gives up 4.94 earned runs. Example: A pitcher has pitched 150 innings and given up 60 earned runs. 1) Divide the number of earned runs (60) by the number of innings pitched (150) =0.40. 2) Then take that number (0.4) and multiply it by 9 =3.60. A pitcher who has pitched 150 innings and given up 60 earned runs has an ERA of 3.60.
In MLB, for pitchers that threw at least 162 innings in a season, that would be Dutch Leonard who had an ERA of 0.96 for the Boston Red Sox in the 1914 season. Leonard pitched 224 2/3 innings and gave up 24 earned runs. For pitchers that threw at least 100 innings in a season it is Tim Keefe who had an ERA of 0.86 for the Troy Trojans in 1880. Keefe pitched 105 innings and gave up 10 earned runs.
A pitcher's era (earned run average) is calculated as follows: 1. Number of Earned Runs 2. Times 9 3. Divided by number of innings pitched So, if a pitcher gives up 3 earned runs in 5 innings then we first multiply 3 times 9 = 27. Then we take 27 and divide it by 5 (for innings pitched) to get an era of 5.4. Also, an earned run is a run that scores without the defense creating any errors.
In 1962, the NL ERA was 3.94 (6,345 earned runs in 14,490 innings pitched) and the AL ERA was 3.97 (6,402 earned runs in 14515 innings pitched) for an MLB average of 3.9553.
It is a measure to judge how effective a pitcher is. It calculated by taking the total earned runs a pitcher has allowed and dividing by (total #of innings pitched/9). Giving you an average number of runs a pitcher allows (earned runs) every 9 innings
1) 1.82 - Ed Walsh - 598 earned runs in 2964 1/3 innings between 1904-1917. 2) 1.89 - Addie Joss - 488 earned runs in 2327 innings between 1902-1910. 3) 2.02 - Jack Pfiester - 240 earned runs in 1067 1/3 innings between 1903-1911. 4) 2.03 - Joe Wood - 324 earned runs in 1436 1/3 innings between 1908-1920. 5) 2.05 - Jim Devlin - 320 earned runs in 1405 innings between 1875-1877. The current (through games of 4/22/09) pitcher with the lowest ERA with 1000+ innings pitched is Mariano Rivera of the New York Yankees with 2.27 - 260 earned runs in 1030 2/3 innings pitched.
For a pitcher to qualify for an earned runs average or wins title in the MLB he must have a minimum of 1.0 innings pitched per game. Therefore he must have a minimum of 162.0 innings pitched for the season
2.76 in the regular season (713 earned runs allowed in 2324 1/3 innings pitched) and 0.95 in the World Series (6 earned runs in 57 innings pitched).
Bob Gibson's regular season ERA was 2.91 (1258 earned runs in 3884 1/3 innings pitched) and his World Series ERA was 1.89 (17 earned runs in 81 innings pitched).
The ERA in baseball stands for Earned Run Average which is the average amount of runs given up by a pitcher per game. For example a 1.98 ERA is amazing but a 6.10 ERA is terrible. The lower your ERA the better.
In the 2001 MLB season, there was a total of 43,287 1/3 innings pitched and 21,215 earned runs allowed for an average ERA of 4.41.