Further Reading: Defensive Metrics and Analysis

Foundational Resources

Academic Papers

  1. "The Value of an Elite Pass Rusher" - MIT Sloan Sports Analytics - Quantifies impact of pressure on offensive efficiency - Develops framework for valuing pass rush - Establishes pressure rate as key metric

  2. "Coverage Metrics and Predictive Value" - Compares stability of coverage metrics - Analyzes what predicts future performance - Recommends target-based over total-based metrics

  3. "Opponent Adjustment Methodology for Defensive Statistics" - Establishes framework for schedule adjustment - Validates adjustment approaches - Provides league-wide benchmarks

  4. "Defensive EPA: Methodology and Application" - Adapts EPA framework for defense - Discusses play-type splits - Compares to traditional metrics

Books

  1. "Football Analytics: Understanding the Game Through Data" - Comprehensive coverage of defensive metrics - Position-specific evaluation chapters - Case studies from professional teams

  2. "The Hidden Game of Football" by Carroll, Palmer, and Thorn - Historical perspective on defensive value - Early development of adjusted statistics - Foundation for modern analytics

  3. "Pro Football Prospectus" (Annual) - DVOA methodology for defense - Team and player rankings - Opponent adjustment approaches

Online Resources

Data Sources

  1. cfbfastR (College Football) - Play-by-play with EPA - Defensive statistics - R/Python access - GitHub: github.com/sportsdataverse/cfbfastR

  2. nflfastR (NFL Reference) - Pass rush data - Coverage targets - Pre-calculated metrics - GitHub: github.com/nflverse/nflfastR

  3. Pro Football Focus (PFF) - Pressure data - Coverage grades - Target-based metrics - Premium subscription required

  4. Sports Info Solutions (SIS) - Detailed charting data - Missed tackle tracking - Coverage assignments

  5. Next Gen Stats (NGS) - Tracking-based metrics - Separation data - Pass rush win rate

Websites and Blogs

  1. Football Outsiders (footballoutsiders.com) - DVOA methodology - Opponent adjustment - Weekly defensive analysis

  2. Open Source Football (opensourcefootball.com) - EPA tutorials - Defensive metrics guides - Code examples

  3. The Athletic (theathletic.com) - In-depth defensive analysis - Advanced statistics coverage - Expert commentary

  4. PFF Edge (pff.com/edge) - Defensive grades methodology - Player evaluation articles - Premium analysis

Tools and Libraries

Python Packages

# Core data manipulation
import pandas as pd
import numpy as np

# Statistical analysis
from scipy import stats
import statsmodels.api as sm

# Machine learning
from sklearn.linear_model import LogisticRegression
from sklearn.ensemble import RandomForestClassifier

# Visualization
import matplotlib.pyplot as plt
import seaborn as sns

# Sports-specific data
# pip install sportsdataverse  # College football
# pip install nfl-data-py       # NFL data

R Packages

# College football data
install.packages("cfbfastR")

# NFL data
install.packages("nflfastR")

# Advanced statistics
install.packages("tidyverse")
install.packages("ggplot2")
install.packages("gt")

Advanced Topics

Pass Rush Analysis

  1. Time to Pressure Models - Measuring first-step quickness - Predicting NFL translation - Resource: Next Gen Stats methodology

  2. Double Team Win Rate - Measuring elite rusher impact - Scheme implications - PFF's double team tracking

  3. Interior vs. Edge Pressure - Comparative value analysis - Scheme-specific impact - Position-specific evaluation

Coverage Analysis

  1. Man vs. Zone Splits - Scheme-specific evaluation - Player fit analysis - Coverage type classification

  2. Target Quality Adjustment - Adjusting for receiver quality faced - Controlling for opportunity - EPA per target models

  3. Separation Data - Tracking-based metrics - Coverage tightness measurement - Next Gen Stats applications

Run Defense

  1. Gap Control Metrics - Assignment-based evaluation - Yards before contact attribution - Scheme responsibility

  2. Tackle Depth Analysis - Contact point measurement - Efficiency beyond tackle totals - Resource: PFF tackle data

  3. Box Count Impact - Run defense with light boxes - Scheme efficiency - Resource: cfbfastR pre-snap data

Research Questions

Team Defense

  1. How much does opponent adjustment change defensive rankings?
  2. What's the relative importance of pass vs. run defense?
  3. How stable are defensive metrics year-over-year?
  4. Does defensive consistency matter more than average performance?

Player Evaluation

  1. Which metrics best predict future pass rush success?
  2. How much of coverage success is scheme vs. player skill?
  3. What's the value of a shutdown corner who is avoided?
  4. How does workload affect defensive player efficiency?

Scheme Analysis

  1. Is blitzing positive EV on average?
  2. What determines man vs. zone effectiveness?
  3. How do defensive fronts affect run stopping?
  4. What's the optimal pressure rate?

Video Resources

YouTube Channels

  1. Brett Kollmann - Defensive film breakdown
  2. JT O'Sullivan (QB School) - Includes coverage analysis
  3. Baldy Breakdowns - Brian Baldinger's analysis
  4. The Film Room - Scheme-focused analysis

Courses and Lectures

  1. MIT Sloan Sports Analytics Conference - Defensive analytics talks
  2. Carnegie Mellon Sports Analytics - Academic perspective
  3. NFL Films - Visual understanding of defense

Community and Forums

Online Communities

  1. r/NFLstatheads - Football analytics discussion
  2. r/CFBAnalysis - College football analytics
  3. Football Outsiders Forums - DVOA methodology discussion
  4. Discord Analytics Communities - Real-time discussion

Twitter/X Accounts

  1. @benbbaldwin - nflfastR creator
  2. @SethWalder - ESPN analytics
  3. @PFF - Pro Football Focus
  4. @NextGenStats - NFL tracking data
  5. @FO_ASchatz - Football Outsiders

Conferences

  1. MIT Sloan Sports Analytics Conference - Premier sports analytics event
  2. NFL Combine Analytics Symposium - NFL-focused
  3. SABR Analytics Conference - General sports analytics
  4. Carnegie Mellon Sports Analytics Conference - Academic focus

Sample Projects

Beginner

  1. Calculate team defensive EPA - Use cfbfastR data - Compare to yards allowed - Visualize differences

  2. Pressure rate vs. sack rate correlation - Analyze relationship - Determine sample size needs - Project future sacks

Intermediate

  1. Coverage grade model - Build composite metric - Weight multiple factors - Validate against PFF grades

  2. Opponent adjustment system - Calculate adjustment factors - Re-rank defenses - Compare to unadjusted

Advanced

  1. Pass rush win rate model - Use tracking data if available - Feature engineering - Predict future success

  2. Defensive play prediction - Predict coverage type - Predict blitz likelihood - Evaluate model accuracy

Week 1-2: Foundation

  • Read Football Outsiders DVOA methodology
  • Calculate basic defensive stats
  • Understand EPA concept

Week 3-4: Pass Defense

  • Implement pressure rate calculations
  • Build coverage grade model
  • Analyze target-based metrics

Week 5-6: Run Defense

  • Calculate stuff rate
  • Analyze yards before contact
  • Build run defense composite

Week 7-8: Integration

  • Implement opponent adjustment
  • Build comprehensive grading system
  • Create visualization dashboard

Ongoing

  • Follow analytics community
  • Analyze weekly data
  • Contribute to open-source projects

Citation Format

When referencing defensive analytics:

Traditional metrics:
- Tackles, Sacks, Interceptions

Advanced metrics:
- Expected Points Added (EPA) - Burke, 2014
- DVOA - Football Outsiders, 2003
- Pass Rush Win Rate - NFL Next Gen Stats
- Coverage Grade - Pro Football Focus
- Opponent-Adjusted Statistics - Various