Key Takeaways: Special Teams Analytics

One-page reference for Chapter 11 concepts


Special Teams Impact

Aspect Value
% of plays ~17%
% of scoring ~15%
Close game impact Decisive in 45%
Field position value ~0.4 EP per 10 yards

Kicker Evaluation

# Expected FG% by distance
def expected_fg(distance):
    if distance <= 20: return 0.99
    elif distance <= 30: return 0.95
    elif distance <= 40: return 0.88
    elif distance <= 50: return 0.75
    elif distance <= 55: return 0.60
    else: return 0.45

# FG Over Expected
fg_over_expected = actual_makes - sum(expected_fg(d) for d in distances)

FG% by Distance Benchmarks

Distance League Avg Elite
0-30 95% 98%+
31-40 88% 92%+
41-50 75% 82%+
51+ 55% 65%+

Punter Evaluation

# Net average
net_avg = gross_yards - return_yards

# Inside 20 rate
inside_20 = (ending_position <= 20).mean()

# Better: EPA per punt
punt_epa = punts['epa'].mean()

Punting Benchmarks

Metric Average Elite
Gross Avg 45 yds 48+ yds
Net Avg 40 yds 43+ yds
Inside 20% 35% 45%+
Touchback% 10% <5%

Return Evaluation

# Kick return value
kr_avg = kickoff_returns['return_yards'].mean()
kr_value = kr_avg * 0.04  # EP per yard

# Punt return value
pr_avg = punt_returns['return_yards'].mean()

# Yards over expected
yoe = actual_yards - (attempts * league_avg)

Return Benchmarks

Type Average Elite
Kick Return 22 yds 27+ yds
Punt Return 8 yds 12+ yds

Coverage Quality

# Coverage score (higher = better)
coverage_score = (
    fair_catch_rate * 100 -
    long_return_rate * 100 -
    avg_return_allowed * 2
)

Field Position Value

Starting Position Expected Points
Own 10 -0.5
Own 25 0.0
Own 40 +0.6
Midfield +1.0
Opp 40 +1.6
Opp 20 +2.5

Every 10 yards ≈ 0.4 EP


Decision Framework

def should_go_for_it(yardline, ytg):
    """Simplified 4th down decision."""
    conv_prob = 0.75 - ytg * 0.05
    go_ev = conv_prob * 2.5 + (1-conv_prob) * (-field_position_value(yardline))
    punt_ev = -field_position_value(yardline - 40)
    return go_ev > punt_ev

Sample Size Warning

Play Type Season n 95% CI Width
FG ~30 ±15%
XP ~45 ±12%
Punts ~60 ±10%
KR ~25 ±18%
PR ~30 ±16%

Small samples = wide confidence intervals


Year-to-Year Stability

Metric Correlation
FG% ~0.35
Punt Net ~0.45
KR Avg ~0.25
PR Avg ~0.20

Lower correlation = higher variance/luck


Team ST Evaluation Framework

1. Kicking
   - FG over expected
   - XP%
   - Kickoff touchback rate

2. Punting
   - Net average
   - Inside 20 rate
   - Hangtime proxy (fair catch rate)

3. Returns
   - KR average
   - PR average
   - Return TDs

4. Coverage
   - KR allowed
   - PR allowed
   - Return TDs allowed

Common Pitfalls

Pitfall Better Approach
Raw FG% FG over expected
Gross punt avg Net average + inside 20
Return yards only Yards over expected
Ignoring samples Wide confidence intervals

Data Sources

Metric Source
FG/XP results Standard PBP
Punt distances Standard PBP
Return yards Standard PBP
Hangtime Not in public data
Individual grades PFF (subscription)

Key Limitations

  • Sample sizes too small for confidence
  • Environment effects hard to model
  • Unit coordination not captured
  • Year-to-year stability moderate
  • High-leverage context difficult

Preview: Part 3

Next: Team Analytics - how individual performances combine into team success and what drives winning.