Is the free throw percentage of a player higher when playing in their stadium?
That's tough to say. At a glance in the NBA, it seems to be, but not by much. However, there isn't a hard and fast rule that says FT% is higher when a player is playing in their home stadium.
For this exercise, I selected six NBA players with 2,500+ free throw attempts at home and 2,500+ free throw attempts on the road and viewed their statistics on Basketball Reference (as of October 30, 2016). Two players have a FT% greater than .800, two players have a FT% between .700 and .800, and two players have a FT% less than .600. The reason for these different "categories" are to detect variance (if any exists).
Player | HFT | HFTA | HFT% | AFT | AFTA | AFT% | DIFF%
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Pau Gasol 2347 3090 .760 2094 2790 .751 .009
LeBron James 3087 4095 .754 3042 4146 .734 .020
Kevin Durant 2261 2565 .881 2354 2664 .884 -.003
Kobe Bryant 4244 5053 .840 4134 4958 .834 .006
Dwight Howard 2235 3971 .563 2213 3864 .573 -.010
Shaq O'Neal 3027 5718 .529 2908 5534 .525 .004
Looking at these statistics, there doesn't seem to be much variance, no matter the FT% (albeit this is a small sample size). The biggest difference in these examples is from LeBron James at .02 in favor of home, but the rest are .01 difference or less either way.
I thought Dwight Howard and Shaq would have a greater difference due to their well-documented ineffectiveness from the free throw line, but that didn't prove to be the case.
Summary:
- If you're great from the free throw line, you'll be great home or away.
- If you're good from the free throw line, you'll be good home or away.
- If you're not so good from the free throw line, you'll be not so good home or away.
Note: This answer considers NBA statistics only. I think collegiate statistics may vary more, but I'm not sure if it would be enough to provide a clear answer to this question.