Interpreting Results¶
Key Metrics¶
Cooperation Rate¶
The most basic metric: what fraction of rounds did the agent play C?
- ~0.65–0.79: Expected range for cooperative LLMs (per Fontana et al.)
- ~0.37: Human baseline in similar experiments
- 1.0: Always cooperates (ALLC)
- 0.0: Always defects (ALLD)
Mutual Cooperation Rate¶
Fraction of rounds where both agents played C. This is the "social welfare" metric — higher is better for both players.
- High (>0.6): Agents found a cooperative equilibrium
- Low (<0.2): Agents are in a defection spiral or one is exploiting the other
Mutual Defection Rate¶
Fraction of rounds where both played D. Indicates failure to cooperate.
- High: Both agents are defensive/retaliatory
- Low: At least one agent is cooperating (or exploiting)
Retaliation Rate¶
After the opponent defects, how often does the agent defect next round?
| Value | Interpretation |
|---|---|
| 1.0 | Perfect retaliation (TFT-like) |
| 0.5 | Sometimes retaliates, sometimes forgives |
| 0.0 | Never retaliates (ALLC-like) — exploitable |
Forgiveness Rate¶
After mutual defection, how often does the agent cooperate next round?
| Value | Interpretation |
|---|---|
| 1.0 | Always tries to rebuild cooperation |
| 0.5 | Sometimes forgives |
| 0.0 | Never forgives (GRIM-like) — defection spiral |
Reading the Cooperation-Over-Time Chart¶
This is the most important visualization. It shows cooperation rate (y-axis) over rounds (x-axis), using a 10-round sliding window.
Common Patterns¶
Sustained Cooperation:
Both agents cooperate throughout. Typical for Cooperative vs. ALLC.Collapse After Exploitation:
Agent cooperates initially, gets exploited, and reduces cooperation. Typical for Cooperative vs. ALLD.TFT Recovery:
Dip in cooperation followed by recovery. Typical for TFT vs. forgiving strategies.End-Game Defection (Fixed Horizon):
Agent cooperates then defects near the end (knowing the game will end). This is why geometric horizon is interesting — it removes this incentive.Comparing Conditions¶
When comparing conditions, look for:
- Level differences: Does one condition produce higher cooperation overall?
- Shape differences: Do the curves have different trajectories?
- Variance: Are replicates consistent? (Need CIs for this — not yet implemented)
- Asymmetry: Does Agent A cooperate more/less than Agent B?
What Makes a "Good" Result?¶
For the research paper, we want to show:
- Replication: LLM cooperation rates match Fontana (~65-79%) ✓
- Novel findings: Communication, protocols, or memory regimes change cooperation dynamics in measurable, statistically significant ways
- Practical implications: Specific recommendations for multi-agent governance (e.g., "Structured protocols reduce exploitation by X%")
For agent design, a good outcome is one where cooperative agents achieve high mutual cooperation without being exploitable — the sweet spot between naivety and paranoia.