Stadium / home team effects in making field goals
DOES IT MATTER WHERE IT IS KICKED? ANALYSIS OF OVER 10,000 ATTEMPTS
Click to enlarge
In our third of not one, not two, but three posts on kicking a football in the NFL, we take on a reader question of whether the stadium / home team matters for making a field goal. We pulled up the data on every field goal since 2002 (over 10,000) of them and plotted the probability of scoring as a function of the stadium in which the field goal was kicked. The results are above. Bars are +/- 1 standard error.
Is it a statistically significant effect? Apparently so:
Pearson's Chi-squared test X-squared = 49.9556, df = 31, p-value = 0.01693
ADDENDUM 1
We had a request to see the broken down by home team or visiting team kicking. Here you go:
Click to enlarge
ADDENDUM 2:
Owing to the generosity of the great reader / Scottish economist Adam Smith (see comments), we now have the stadiums broken down by door (indoor or outdoor). The gray stadiums are either convertible (Houston) or have a small hole in the roof (Dallas).
Correlation is not causation, but it sure does seem plausible that having an indoor stadium helps the kicker.
Click to enlarge
APPENDIX
To decode the team names, use this list:
ARI: Arizona Cardinals ATL: Atlanta Falcons BAL: Baltimore Ravens BUF: Buffalo Bills CAR: Carolina Panthers CHI: Chicago Bears CIN: Cincinnati Bengals CLE: Cleveland Browns DAL: Dallas Cowboys DEN: Denver Broncos DET: Detroit Lions GB: Green Bay Packers HOU: Houston Texans IND: Indianapolis Colts JAX: Jacksonville Jaguars KC: Kansas City Chiefs MIA: Miami Dolphins MIN: Minnesota Vikings NE: New England Patriots NO: New Orleans Saints NYG: New York Giants NYJ: New York Jets OAK: Oakland Raiders PHI: Philadelphia Eagles PIT: Pittsburgh Steelers SD: San Diego Chargers SEA: Seattle Seahawks SF: San Francisco 49ers STL: Saint Louis Rams TB: Tampa Bay Buccaneers TEN Tennessee Titans WAS: Washington Redskins
Figure 1 Data:
Stadium Miss Hit ARI 67 292 ATL 45 257 BAL 45 322 BUF 61 253 CAR 51 269 CHI 64 295 CIN 53 293 CLE 56 266 DAL 53 281 DEN 50 303 DET 34 285 GB 72 274 HOU 53 271 IND 55 308 JAC 64 252 KC 58 285 MIA 58 286 MIN 35 267 NE 63 282 NO 48 285 NYG 59 271 NYJ 50 260 OAK 72 297 PHI 51 300 PIT 65 259 SD 48 258 SEA 55 285 SF 51 289 STL 50 284 TB 58 256 TEN 63 288 WAS 70 254
Figure 2 Data:
ARI Home_Team_Kicks 32 152
Visiting_Team_Kicks 35 140
ATL Home_Team_Kicks 24 142
Visiting_Team_Kicks 21 115
BAL Home_Team_Kicks 23 187
Visiting_Team_Kicks 22 135
BUF Home_Team_Kicks 36 129
Visiting_Team_Kicks 25 124
CAR Home_Team_Kicks 23 125
Visiting_Team_Kicks 28 144
CHI Home_Team_Kicks 32 150
Visiting_Team_Kicks 32 145
CIN Home_Team_Kicks 28 162
Visiting_Team_Kicks 25 131
CLE Home_Team_Kicks 20 130
Visiting_Team_Kicks 36 136
DAL Home_Team_Kicks 30 138
Visiting_Team_Kicks 23 143
DEN Home_Team_Kicks 23 154
Visiting_Team_Kicks 27 149
DET Home_Team_Kicks 17 152
Visiting_Team_Kicks 17 133
GB Home_Team_Kicks 39 144
Visiting_Team_Kicks 33 130
HOU Home_Team_Kicks 32 131
Visiting_Team_Kicks 21 140
IND Home_Team_Kicks 19 166
Visiting_Team_Kicks 36 142
JAC Home_Team_Kicks 36 131
Visiting_Team_Kicks 28 121
KC Home_Team_Kicks 29 127
Visiting_Team_Kicks 29 158
MIA Home_Team_Kicks 32 141
Visiting_Team_Kicks 26 145
MIN Home_Team_Kicks 11 138
Visiting_Team_Kicks 24 129
NE Home_Team_Kicks 30 164
Visiting_Team_Kicks 33 118
NO Home_Team_Kicks 22 129
Visiting_Team_Kicks 26 156
NYG Home_Team_Kicks 27 138
Visiting_Team_Kicks 32 133
NYJ Home_Team_Kicks 26 138
Visiting_Team_Kicks 24 122
OAK Home_Team_Kicks 29 150
Visiting_Team_Kicks 43 147
PHI Home_Team_Kicks 25 176
Visiting_Team_Kicks 26 124
PIT Home_Team_Kicks 34 149
Visiting_Team_Kicks 31 110
SD Home_Team_Kicks 23 134
Visiting_Team_Kicks 25 124
SEA Home_Team_Kicks 19 145
Visiting_Team_Kicks 36 140
SF Home_Team_Kicks 25 156
Visiting_Team_Kicks 26 133
STL Home_Team_Kicks 22 142
Visiting_Team_Kicks 28 142
TB Home_Team_Kicks 30 136
Visiting_Team_Kicks 28 120
TEN Home_Team_Kicks 28 155
Visiting_Team_Kicks 35 133
WAS Home_Team_Kicks 39 124
Visiting_Team_Kicks 31 130
Figure 3 Data: See Figure 1 data plus the comments
Graphs were made in R using Hadley Wickham’s ggplot2 package. Pointer to the data can be found at our previous post.
Stadium In/Out
ARI Out
ATL In
BAL Out
BUF Out
CAR Out
CHI Out
CIN Out
CLE Out
DAL mostly In (weird hole in roof)
DEN Out
DET In
GB Out
HOU In/out (retractable roof); no log of roof status available
IND In
JAC Out
KC Out
MIA Out
MIN In
NE Out
NO In
NYG Out
NYJ Out
OAK Out
PHI Out
PIT Out
SD Out (but it is San Diego!)
SEA Open
SF Open
STL In
TB Out
TEN Out
WAS Out
February 13, 2013 @ 2:58 pm
Sorry, I mean “In” for SEA and SF
February 13, 2013 @ 2:59 pm
Crap, make that “Out” for SEA and SF… Third time, right?
February 13, 2013 @ 2:59 pm
Are these conditionalized on distance? If not, then would the rational approach be for coaches in ‘good’ stadiums to go for longer kicks (and shorter kicks in ‘bad’ stadiums), so that all venues approach the same success rate?
February 14, 2013 @ 9:11 am
Hi Rob,
I could condition on distance in a regression model (though it would be hard to make pretty graphs from the result :). My prior is that this won’t matter much since, in general, the home and visiting teams tend to have rather correlated performance in a given stadium.
February 14, 2013 @ 9:15 am
One remark. Seemingly, with Tukey’s hsd test, only DET and WAS are found different (by Matlab, with P-value of 0.04). The rest of the Stadium are not different, with alpha 0.1.
February 14, 2013 @ 9:46 am
jr – I’d believe that. For the novice readers I should mention that there’s no contradiction implied by finding a variable to be significant when no pair is significant in a post hoc test.
February 14, 2013 @ 10:06 am
Hey Dan,
Since teams tend to have the same kicker across multiple years, could kicker-effects be driving the result? It could even be that some teams consistently attempt shorter/longer field goals (which is something you could control for). There’s probably even some persistence in visiting teams’ kicking performance because each team plays 6 division games each year against the same three teams.
February 15, 2013 @ 2:51 pm