戰昇的部落格

以下是Week 13的課程內容摘要與心得，今天的講義包括「Repeated Game」、「Collusion」、「Consolidation」。以下是這週的重點整理：

一、重複博弈 (Repeated Game)

1. 重複博弈的應用

- 討論有限次與無限次重複博弈，分析企業如何透過長期合作提高獲益。

- 例如，航空公司限制運輸容量以維持高票價。

2. 均衡策略的特性

- 使用折現因子 delta 評估未來回報的影響。

- 修改版的「Grim Trigger」策略作為懲罰背叛的有效威脅，避免背叛。

二、合謀行為 (Collusion)

1. 合謀的特徵與範例

- 討論市場中企業如何透過合謀固定價格，例如OPEC控制石油供應、LCD製造商操控價格。

2. 穩定合謀的條件

- 透過重複博弈分析，當折現因子 delta > 0.5294  時，企業合謀更可能持續。

3. 反壟斷政策的挑戰

- 合謀多為默契式，難以在法院中舉證。

- 政府透過反壟斷政策，如罰款與調查，來威懾合謀行為。

三、市場整合 (Consolidation)

1. 市場整合的概念

- 討論企業合併、收購如何影響市場結構。

- 大型企業可能因為規模經濟與市場力量獲益。

2. 政策干預的影響

- 討論政府如何通過反壟斷法規限制企業整合的負面影響。

心得總結

這週的課程讓我深入理解重複博弈與合謀行為在市場中的應用，尤其是在企業如何平衡合作與背叛之間的取捨中，重複博弈策略顯得至關重要。合謀的分析讓我體會到反壟斷政策的重要性，尤其是在維持市場公平競爭中的挑戰。

然而，對於複雜的數學模型推導仍需多加練習，尤其是計算折現因子與其對合謀穩定性的影響。在未來課程中，我期待學習更多關於政策如何平衡市場效率與公平性的案例分析。

Below is the summary and reflection for Week 13. Today’s lecture covered Repeated Game, Collusion, and Consolidation. Here are the key points from this week:

A. Repeated Game

1. Applications of Repeated Games

- Discussed finite and infinite repeated games and analyzed how firms use long-term cooperation to increase profits.

- For example, airlines limiting transportation capacity to maintain high ticket prices.

2. Characteristics of Equilibrium Strategies

- Evaluated the impact of future returns using the discount factor \( \delta \).

- The modified "Grim Trigger" strategy serves as an effective threat to punish betrayal, discouraging defection.

B. Collusion

1. Features and Examples of Collusion

- Examined how firms collude to fix prices in markets, such as OPEC controlling oil supply or LCD manufacturers manipulating prices.

2. Conditions for Stable Collusion

- Through repeated game analysis, collusion is more likely to persist when the discount factor delta > 0.5294 

3. Challenges of Antitrust Policies

- Most collusion is tacit and difficult to prove in court.

- Governments deter collusion through antitrust policies, such as fines and investigations.

C. Market Consolidation

1. Concept of Market Consolidation

- Discussed how mergers and acquisitions impact market structure.

- Large firms benefit from economies of scale and market power.

2. Impact of Policy Intervention

- Analyzed how governments use antitrust laws to mitigate the negative effects of market consolidation.

Reflection Summary

This week’s lecture provided a deeper understanding of how repeated games and collusion function in markets. The strategies in repeated games, particularly the balance between cooperation and defection, are crucial for firms. The analysis of collusion highlighted the importance of antitrust policies and the challenges of maintaining fair competition in markets.

However, I still find the mathematical models, especially calculating the discount factor and its impact on collusion stability, to be challenging. I hope to practice these aspects further. In future lectures, I look forward to learning more about how policies balance market efficiency and fairness through case studies.