Over on the Orlando Magic site Third Quarter Collapse is a FanPost with statistical analysis on referees that I find interesting. Especially who falls out of the two standard deviations (very few in each category). Measured were Games Refereed, Home Win %, Total Points Per Game, Total Fouls Per Game, Home and Road Foul %, and Home and Road Technicals Per Game. Especially this:

"Fouls per game had a mean of 42.08, with a standard deviation of 1.41. Normal was 39.26 to 44.90 fouls per game. This stat had four deviants, again all low. David Guthrie (38.4), Gary Zielinski (39.2), Ken Mauer (39.0), and Steve Javie (38.8) were on the most lenient crews in basketball.

Road Foul % averaged 50.96%, with a standard deviation of 0.81%, meaning the range was 49.34% to 52.59%. There were three deviants, one low and two high. The low was Violet Palmer, whose crews called only 48.8% of fouls against the road team. High were Courtney Kirkland (52.6%) and Ron Garretson (52.8%)."

Might help to explain why some refs are more popular with home crowds, however slightly their deviations? (Emphasis mine)