Using a different method, I estimate the league league LEAGUE road rates for Yaz' career to be .309 and .362 on base and slugging percentage. His career road rates were .357 and.422.

That would give him a relative OB% of 1.155 and a relative slugging percentage of 1.166 for a road OPS+ of 132.

Once more I've decided to calculate Yaz home OPS+ relative to park and home field advantage. Since the league road rates for his career are .309 and .362, and his overall league rates adjusted for ballpark are .334 and .398, then the home rates that should be used for the league to calculate his home OPS+ are .359 and .434.

his home rates once again were .408 and .503 which would give him a home relativized relative OB% of 1.136 and a home relativized relative slugging of 1.159 for an overall home relative OPS+ of 129.5

So it turns out Yaz actually was just as good of a relative hitter on the road and outside of Fenway as he was a relative hitter at home and in Fenway.

Here's the crux of it.

League road rates: .309/.362

his road rates: .359/.422

OPS+ about 132.5

League home rates adjusted for Fenway: .359/.434

His home rates: .408/.503

OPS+ about 129.5

Compare the league adjusted rates on the road to the league adjusted rates in Fenway with a normal home field advantage:

LEAGUE

Road to Home/Boston

.309 to .359

.362 to .434

That's what an average player would be expected to do in each of those settings, but ultimately the point is that his .359/.422 rates on the road versus a league that went .309 and .359 on the road are just as good as his home rates were relative to his home park, if not a little better.

My earlier estimates tried to estimate league adjusted rates from park factors which ended up being inaccurate and surprising.

Consider that Boston has a park factor of about 107, meaning that it produced about 114% of the league average offense, all else being equal, however Boston produced about 11% higher on base percentage and 15% higher slugging percentage than the rest of the league. That means that an average hitter in Boston would have a 126 OPS+ if we didn't account for park factors, and yet we only get 14% more offense. If the "ops+ is linear with offense" hypothesis were true we'd expect scoring to be 26% higher in Boston, but park factors say it was only 14% higher.

That would give him a relative OB% of 1.155 and a relative slugging percentage of 1.166 for a road OPS+ of 132.

Once more I've decided to calculate Yaz home OPS+ relative to park and home field advantage. Since the league road rates for his career are .309 and .362, and his overall league rates adjusted for ballpark are .334 and .398, then the home rates that should be used for the league to calculate his home OPS+ are .359 and .434.

his home rates once again were .408 and .503 which would give him a home relativized relative OB% of 1.136 and a home relativized relative slugging of 1.159 for an overall home relative OPS+ of 129.5

So it turns out Yaz actually was just as good of a relative hitter on the road and outside of Fenway as he was a relative hitter at home and in Fenway.

Here's the crux of it.

League road rates: .309/.362

his road rates: .359/.422

OPS+ about 132.5

League home rates adjusted for Fenway: .359/.434

His home rates: .408/.503

OPS+ about 129.5

Compare the league adjusted rates on the road to the league adjusted rates in Fenway with a normal home field advantage:

LEAGUE

Road to Home/Boston

.309 to .359

.362 to .434

That's what an average player would be expected to do in each of those settings, but ultimately the point is that his .359/.422 rates on the road versus a league that went .309 and .359 on the road are just as good as his home rates were relative to his home park, if not a little better.

My earlier estimates tried to estimate league adjusted rates from park factors which ended up being inaccurate and surprising.

Consider that Boston has a park factor of about 107, meaning that it produced about 114% of the league average offense, all else being equal, however Boston produced about 11% higher on base percentage and 15% higher slugging percentage than the rest of the league. That means that an average hitter in Boston would have a 126 OPS+ if we didn't account for park factors, and yet we only get 14% more offense. If the "ops+ is linear with offense" hypothesis were true we'd expect scoring to be 26% higher in Boston, but park factors say it was only 14% higher.

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