Pekka Rinne, career:
at Home: 42-17-5, 2.21, .924, 29.12 SA/60
on Road: 20-15-4, 2.87, .897, 27.84 SA/60
Those splits certainly make one at least a bit skeptical about whether Rinne's save percentage is being accurately reported in his home rink in the Music City, and whether we can therefore rely on those numbers to accurately reflect his performance. Nashville has been one of the places suspected of a shot recording bias (for more info see Tom Awad or JLikens), which increases the probability that there may be overcounting going on in Rinne's favour.
Unfortunately, this case is not entirely clear cut, because former Predators goalie Dan Ellis doesn't have the same extreme splits. In fact, Ellis actually has a higher career save percentage on the road despite playing all but one game of his career for the same Predators team as Rinne:
Dan Ellis, career:
at Home: 18-16-5, 2.59, .910, 28.82 SA/60
on Road: 32-26-5, 2.68, .913, 30.78 SA/60
Backup goalies can sometimes have skewed numbers because of relief appearances, but even after taking out the 12 games where Ellis came in off the bench, the pattern persists:
at Home: 18-15-4, 2.57, .913, 29.58 SA/60
on Road: 30-22-4, 2.65, .916, 31.62 SA/60
This is a fairly small sample for both Rinne and Ellis, and I expect that some of the effect is simple random variance. It is likely that the .027 difference between Rinne's home and road performance has been a bit of a statistical quirk, as has his good fortune to face almost 4 fewer shots against per game than Dan Ellis while on the road, but I'm still slightly suspicious of the official scorer in Nashville. It will be interesting to see if similar results continue this season with Ellis in Tampa and Rinne expected to once again be the main man in the crease in Nashville.