The raw data behind the story "The Best MLB All-Star Teams Ever" https://fivethirtyeight.com/features/the-best-mlb-all-star-teams-ever/.

mlb_as_play_talent

Format

A data frame with 3930 rows representing Major League Baseball players in given seasons and 15 variables:

bbref_id

Player's ID at Baseball-Reference.com

yearid

The season in question

gamenum

Order of All-Star Game for the season (in years w/ multiple ASGs; set to 0 when only 1 per year)

gameid

Game ID at Baseball-Reference.com

lgid

League of All-Star team

startingpos

Position (according to baseball convention; 1=pitcher, 2=catcher, etc.) if starter

off600

Estimate of offensive talent, in runs above league average per 600 plate appearances

def600

Estimate of fielding talent, in runs above league average per 600 plate appearances

pitch200

Estimate of pitching talent, in runs above league average per 200 innings pitched

asg_pa

Number of plate appearances in the All-Star Game itself

asg_ip

Number of innings pitched in the All-Star Game itself

offper9innasg

Expected offensive runs added above average (from talent) based on PA in ASG, scaled to a 9-inning game

defper9innasg

Expected defensive runs added above average (from talent) based on PA in ASG, scaled to a 9-inning game

pitper9innasg

Expected pitching runs added above average (from talent) based on IP in ASG, scaled to a 9-inning game

totper9innasg

Expected runs added above average (from talent) based on PA/IP in ASG, scaled to a 9-inning game

Source

http://baseball-reference.com , http://chadwick-bureau.com, Fangraphs