Case Study 2: Win Shares for Career Evaluation - Comparing All-Time Greats

Introduction

Win Shares provides a cumulative measure that naturally lends itself to career comparisons. This case study examines how Win Shares evaluates all-time great players and what the metric reveals about different paths to basketball immortality.

The All-Time Win Shares Leaders

Career Win Shares Top 10 (Through 2024)

Paths to Greatness

The Longevity Path: Kareem Abdul-Jabbar

Profile: - 20 seasons - Career WS: 273.4 - Never had an exceptional WS/48 season (peak 0.292) - But maintained high level (>10 WS) for 15 consecutive seasons

Win Shares Story: Kareem's total accumulation came from unprecedented durability. He played 1,560 games (most ever at retirement), averaging 13.7 WS per season from ages 22-40.

Key Insight: Win Shares rewards longevity. Kareem's total exceeds players with higher peaks but shorter careers.

The Peak Path: Michael Jordan

Profile: - 15 seasons (plus partial comeback seasons) - Career WS: 214.0 - Highest career WS/48: 0.250 - Multiple seasons with 20+ WS

Win Shares Story: Jordan's career Win Shares understate his dominance relative to peak impact. His WS/48 of 0.250 is among the highest ever for players with significant careers.

Key Insight: Jordan's Wizards seasons (13.3 WS at age 38-40) helped his career total but lowered his career WS/48 from 0.260 to 0.250.

The Balanced Path: Tim Duncan

Profile: - 19 seasons - Career WS: 206.4 - Remarkably consistent (11-15 WS range for most of career) - Elite two-way contribution

Win Shares Story: Duncan's OWS and DWS were remarkably balanced throughout his career:

Key Insight: Duncan's defensive excellence (87.7 career DWS) is captured well by Win Shares, distinguishing him from pure scorers.

The Volume Path: Karl Malone

Profile: - 19 seasons - Career WS: 234.6 - Extremely durable (1,476 games) - High-volume scorer with average efficiency

Win Shares Story: Malone accumulated Win Shares through extraordinary volume: - 36,928 career points (2nd all-time at retirement) - 27.4 MPG through age 39 - Never missed significant time to injury

Win Shares Critique: Some argue Malone's Win Shares total overstates his value relative to peers. His playoff record (1-4 in Finals) suggests regular season Win Shares don't capture clutch/playoff value.

Comparative Analysis

Adjusting for Era

Win Shares totals depend on era context:

Higher Pace Eras (1960s, 1980s): - More possessions = more opportunity for Win Shares - Wilt's 247 WS in 14 seasons benefited from pace

Lower Pace Eras (1990s-2000s): - Fewer possessions reduced Win Shares opportunities - Jordan's 214 WS in 15 seasons was in slower era

Era-Adjusted WS/48:

Position Comparisons

Win Shares varies by position due to different contribution patterns:

Centers (Traditional): - Historically highest WS due to rebounding credit - Kareem, Wilt, Shaq dominated Win Shares

Guards: - Lower DWS typically limits totals - Jordan, Magic exceptional among guards

Modern Positionless: - LeBron, Giannis blur categories - Can accumulate both OWS and DWS

Win Shares per Championship

Analyzing Win Shares accumulated during championship seasons:

Insight: Jordan's championship seasons averaged the highest Win Shares, suggesting peak performance in winning contexts.

Case Comparison: Jordan vs. LeBron

Career Arc Comparison

Jordan Advantages: - Higher peak WS/48 (0.268 vs. 0.218) - More 20+ WS seasons (3 vs. 1) - Higher WS in championship contexts

LeBron Advantages: - More total seasons at high level - Will likely pass Kareem's total - More consistent (never fell below 5 WS until very late career)

What Win Shares Reveals

1. Peak vs. longevity trade-off: Jordan higher peaks, LeBron longer career
2. Efficiency matters: Jordan's WS/48 edge reflects higher efficiency
3. Two-way value: Both have strong OWS and DWS, unlike pure scorers
4. Era context: Direct comparison complicated by era differences

Limitations in Historical Comparisons

Data Quality Issues

Pre-1973-74: - Win Shares estimated with less precision - Some statistics unavailable - Wilt's numbers involve assumptions

Rule Changes: - Three-point line (1979) - Zone defense legalization (2001) - Pace variations across eras

Contextual Factors Not Captured

1. Teammate quality: Playing with other stars affects opportunities
2. System effects: Some systems inflate individual statistics
3. Competition level: League depth varies by era
4. Load management: Modern rest patterns reduce counting stats

Conclusions

What Win Shares Gets Right

1. Longevity reward: Appropriately credits sustained excellence
2. Efficiency capture: Higher efficiency = higher WS/48
3. Two-way credit: Both offense and defense contribute
4. Relative ranking: Top 10 includes consensus all-time greats

What Win Shares Misses

1. Playoff performance: Regular season focus limits championship context
2. Era adjustment: Raw totals not directly comparable
3. Team context: Good teams inflate individual Win Shares
4. Peak value: Career totals may underweight transcendent peaks

Recommendations for Career Evaluation

1. Use both career WS (total) and WS/48 (rate)
2. Consider era and position context
3. Supplement with playoff Win Shares
4. Integrate with other metrics (BPM, VORP, etc.)

Discussion Questions

1. Should career Win Shares totals or WS/48 rates be weighted more heavily in all-time rankings?

2. How should we adjust Win Shares for different eras when comparing players?

3. Does Kareem's Win Shares total accurately reflect his all-time ranking relative to Jordan and LeBron?

4. What adjustments to Win Shares would improve its utility for historical comparisons?

Data Exercise

Using Basketball-Reference career data:

1. Calculate WS/48 for all players with 200+ career Win Shares
2. Identify the 10 most efficient players (by WS/48) among those with 150+ career Win Shares
3. Analyze the relationship between career length and career WS/48 for Hall of Famers
4. Create an era-adjusted Win Shares metric and rerank the all-time top 10