Considering era, park, Gwynn was the best

Tony Gwynn is the best hitter for average of all time.

That declarative statement is courtesy of Michael J. Schell, a professor of biostatistics at the University of North Carolina and author of “Baseball’s All-Time Best Hitters: How Statistics Can Level the Playing Field” (1999).

Traditionally, Ty Cobb has held the title of the best hitter for average. His .366 career batting average is the best of all time.

Gwynn, who was inducted into the Baseball Hall of Fame yesterday for his eight batting titles and 3,141 hits with the San Diego Padres, hit .338 — 17th among players with 4,000 at-bats.

Schell closes that gap and then some with four adjustments.

He eliminates the decline phase of long careers, using only a player’s first 8,000 at-bats.

Cobb’s average improves to .370. Gwynn’s improves to .340.

Schell adjusts for playing in different eras, using the mean batting average of a season.

Cobb remains at .370. Gwynn’s moves down to .338, but he moves up to seventh place, with other hitters being adjusted down.

The third variable is the talent pool of an era — how hard was it to dominate, integration, expansion, the designated hitter.

Cobb moves down to .346, still in first place. Gwynn improves to .339, moving into second place.

Finally, there are ballpark effects. Cobb played in the best hitter’s park in the American League. Gwynn played in a pitcher’s park.

Gwynn’s average is adjusted to .342. Cobb finishes at .340.

While Schell provides thorough statistical analysis, George F. Will examines the human side of Gwynn’s hitting in “Men at Work: The Craft of Baseball” (1990).

Will’s chapter on Gwynn concentrates on the 1988 season, when he won his third batting title with a .313 average, the lowest ever for a National League batting champion.

In spring training, Gwynn had surgery on his left hand. After 13 games, he was hitting .244.

Then Gwynn hit the disabled list after spraining his thumb rounding first base in Pittsburgh. On June 13, he was hitting .237.

But he hit .406 in July and .367 in the last 73 games of the season to finish at .313.

Gwynn won the batting title by watching videotapes of his previous at-bats, from 1984 when he won his first batting title (.351) and from 1987 when he won his second (.370).

Gwynn kept a taped record of every at-bat, starting with his first one. He was the first to use this technology, and it is his legacy.

Now every ballpark is equipped with a film room, where players can prepare for pitchers before the game or even between at-bats.

Early in his career, Gwynn was chided for lugging videotapes on the road. Yesterday, it paid off.