Officiating Statistics The NFL zebras come under intense scrutiny for their calls (and non-calls) and for several years now they have also had to suffer the indignity of instant replay. How significant is the influence an officiating crew exerts on the way a game plays out?

Handicappers looking to get an edge are often found digging around in areas that the casual fan doesn't give much thought to, in the hopes that they come across some nugget of predictive value. While there has been attention placed on baseball umpires, NBA officials and other sports arbiters for their possible effects on the outcome of a game, we haven't come across much on NFL officials, even though their calls are more commonly found to be controversial.

We start by compiling data for the 2002 regular season games, and since the officiating crew tends to stay together throughout the season, we'll identify the NFL flag-throwers by the referee who heads up the unit.

In terms of attempting to find bias in how the crew calls a game, two things spring to mind:

• the record of the home team in the games they call may be indicative of a crew's favoritism (or lack thereof -- a crew might be overly generous to the away team in an attempt to prove they are impartial)
• the total scoring of both teams in a game may suggest a crew's officiating "style" lends itself more to benefit of the offense or the defense

ANALYSIS: Of the seventeen refs above, six had records that were slightly away from the norm (33% or less, 67% or higher). That may seem to be suggestive of a possible bias on the part of the crew towards either the home (67%+) or away (33% or less) sides. Of course with random coin-flip series of fifteen tosses, you'd expect about three of every ten series to be in the <34/67+ group, so it's easy to believe the numbers are just a matter of normal (random) distribution over a small set of games.

Still, if you were a conspiracy-theory lover, you would turn your attention first to the games overseen by Carey, White, McAuley, Blum, Hochuli, and Kukar.

Perhaps, we thought, there might be a bias as well towards favorites/underdogs or even better, an officiating crew that likes to keep games "close" and would thus provide very favorable situations for a large underdog to over-achieve! Well, when we defined a "big favorite game" as one with a five plus point line, two of the names on our "list of six" reappear: the big dog covered 6 of 7 in Kukar games, and 5 of 6 in Blum games. Those are again a tiny number of events to worry about however.

Turning to the over/under tallies --

Another case of six of the seventeen being somewhat divergent, but again not in a particularly statistically significant way. Playing under in Carey-led games, and over in Leavy-led games was a winning strategy in 2002, but the real question is was there any kind of historical precedent on those two crews?

There's only one way to find out -- build another year's worth of "ref stats" and re-test! We'll come back with an update in the not too distant future.