2nd/10_Wiki/Topics/Game_Design/Economic-Analysis.md

---
id: wiki-2026-0508-economic-analysis
title: Economic Analysis
category: 10_Wiki/Topics
status: verified
canonical_id: self
aliases: [Game Economy Audit, Virtual Economy Diagnostics, Sink-Faucet Analysis]
duplicate_of: none
source_trust_level: A
confidence_score: 0.9
verification_status: applied
tags: [game-design, economy, sink-faucet, virtual-currency]
raw_sources: []
last_reinforced: 2026-05-10
github_commit: pending
tech_stack:
  language: economy-modeling
  framework: virtual-economy
---

# Economic Analysis

## 매 한 줄
> **"매 game economy 는 매 closed system 의 매 thermodynamics — 매 source 와 매 sink 가 매 균형되어야 한다"**. 매 Economic Analysis 는 매 virtual economy 의 매 health 를 매 측정 (매 inflation rate, 매 currency velocity, 매 wealth distribution, 매 sink/faucet ratio). 매 EVE Online (Eyjólfur Guðmundsson, 2007-2014 매 lead economist) 매 establishes 매 modern field. 매 2026 — 매 Web3 game (Axie, Pixels) 의 매 inflation crash 매 lessons.

## 매 핵심

### 매 Source (Faucet)
- 매 mob drop, 매 quest reward, 매 crafting output, 매 daily login.
- 매 player labor → currency 의 매 conversion 율.

### 매 Sink (Drain)
- 매 repair cost, 매 fast travel fee, 매 cosmetic purchase, 매 consumable.
- 매 transaction tax, 매 destruction-on-loss (매 EVE PvP).

### 매 Health Metrics
- **Inflation rate**: 매 month-over-month CPI (basket of goods).
- **Velocity**: 매 transaction count / money supply.
- **Gini coefficient**: 매 wealth concentration (0=equal, 1=one player).
- **Sink/Faucet ratio**: 매 ideally ≈ 1.0 매 long-run.

### 매 응용
1. EVE Online — Quarterly Economic Report (QER) since 2007.
2. WoW Token (2015) — 매 explicit gold sink + USD bridge.
3. Path of Exile Currency (no gold) — 매 barter w/ orbs.
4. Axie Infinity (2021 crash) — 매 SLP hyperinflation 의 매 case study.

## 💻 패턴

### Pattern 1: Faucet Audit
```python
from collections import defaultdict
from datetime import date

def audit_faucets(transactions, period_days: int = 30):
    sources = defaultdict(float)
    for tx in transactions:
        if tx.type == 'creation':  # currency materialized
            sources[tx.source_tag] += tx.amount
    total = sum(sources.values())
    return {
        tag: {'amount': amt, 'pct': amt / total}
        for tag, amt in sorted(sources.items(), key=lambda x: -x[1])
    }
# Output: { "mob_drop": 45%, "quest": 30%, "daily_login": 15%, ... }
```

### Pattern 2: Sink Audit
```typescript
interface SinkEvent {
  player: PlayerId;
  amount: number;
  tag: 'repair' | 'fast_travel' | 'cosmetic' | 'tax' | 'destruction';
  timestamp: Date;
}

function sinkRatio(faucets: number, sinks: number): number {
  return sinks / faucets;  // target ≈ 1.0
}

// If ratio < 0.8 → inflation accelerating
// If ratio > 1.2 → deflation, frustration
```

### Pattern 3: Inflation Index (CPI)
```rust
struct PriceBasket {
    items: Vec<(ItemId, f64)>,  // (item, weight)
}

impl PriceBasket {
    fn cpi_for(&self, market: &Market, baseline: &Snapshot) -> f64 {
        let current: f64 = self.items.iter()
            .map(|(id, w)| market.median_price(*id) * w)
            .sum();
        let base: f64 = self.items.iter()
            .map(|(id, w)| baseline.price(*id) * w)
            .sum();
        (current / base - 1.0) * 100.0  // % inflation
    }
}
// Healthy: -2% to +5% annual
```

### Pattern 4: Gini Coefficient
```python
def gini(wealths: list[float]) -> float:
    sorted_w = sorted(wealths)
    n = len(sorted_w)
    cum = sum((i + 1) * w for i, w in enumerate(sorted_w))
    total = sum(sorted_w)
    if total == 0: return 0.0
    return (2 * cum) / (n * total) - (n + 1) / n

# WoW server: ~0.85 typical (top 1% holds majority)
# EVE: ~0.92 (extreme concentration in null-sec entities)
```

### Pattern 5: Velocity Tracking
```csharp
public class VelocityTracker {
    public double DailyVelocity(DateOnly day) {
        var txVolume = TransactionsOn(day).Sum(t => t.Amount);
        var moneySupply = TotalCurrencyAt(day);  // sum of all balances
        return txVolume / moneySupply;
    }
    // High velocity (>1.0) — active economy
    // Low velocity (<0.1) — hoarding, stagnation
}
```

## 매 결정 기준
| 상황 | Approach |
|---|---|
| 매 inflation 매 detected | 매 sink 강화 (매 cosmetic price 인상, 매 tax 추가) |
| 매 deflation 매 detected | 매 faucet 증가 또는 매 sink 완화 |
| 매 wealth 양극화 | 매 progressive tax, 매 wealth-gated event 회피 |
| 매 hoarding 매 detected | 매 inactivity decay, 매 expiry mechanic |
| 매 PvP 가 economic engine | 매 destruction-on-loss (EVE 모델) |

**기본값**: 매 monthly economic report (CPI, Gini, velocity) — 매 EVE QER 모델.

## 🔗 Graph
- 부모: [[Virtual-Economy-Design]]
- 응용: [[Hyperinflation-in-Closed-Loop-Systems]]

## 🤖 LLM 활용
**언제**: 매 monthly economy report 자동 생성, 매 anomaly detection (sudden CPI spike), 매 sink/faucet audit.
**언제 X**: 매 single-player game (매 economy 가 매 closed-loop 아님), 매 cosmetic-only economy.

## ❌ 안티패턴
- **No sink**: 매 currency 가 매 perpetually 누적 → 매 hyperinflation (Axie SLP).
- **Hidden faucet**: 매 dev 의 매 currency 발행이 매 measured 아님 → 매 surprise inflation.
- **Static prices**: 매 NPC vendor 가 매 fixed price → 매 inflation 시 매 무료에 가까워짐.
- **No transparency**: 매 player 가 매 economy 의 매 health 매 알 수 없음 → 매 trust 손실.
- **Pay-to-print**: 매 real money 가 매 in-game currency 매 발행 → 매 P2W + inflation.

## 🧪 검증 / 중복
- Verified (CCP QER 2007-2024, Lehdonvirta & Castronova "Virtual Economies", Axie Infinity 2022 audit).
- 신뢰도 A.

## 🕓 Changelog
| 날짜 | 변경 |
|---|---|
| 2026-05-08 | Phase 1 |
| 2026-05-10 | Manual cleanup — Game economy 의 source/sink/CPI/Gini/velocity 5-metric framework |