Here are Mantle's career numbers:
Mantle walked in 20% of his plate appearances (PA) at home against righty pitchers, only 13.6% against southpaws. Even on the road he walked at a higher rate against righties: 18.2% to 15%. This accounts for all four of his on base percentages (OBP) being over .400 despite his road batting average against righties being only .271.
At home he made up a 29 point (.029) deficit in BA against righty pitchers for OBP that exceeded that against southpaws by 21 points (.021).
Pitchers feared his home run power, especially when The Mick batted lefty at home in Yankee Stadium. AB/HR home: 19.5 v lefties, 13.1 v righties; road almost dead even: 15.15, 15.33.
Subsequent posts will include graphs of annual data.