Stadium / home team effects in making field goals

February 13, 2013
By

(This article was first published on Decision Science News » R, and kindly contributed to R-bloggers)

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
```

We had a request to see the broken down by home team or visiting team kicking. Here you go:

Click to enlarge

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
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:

```
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.

The post Stadium / home team effects in making field goals appeared first on Decision Science News.

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