最適品質管制下Cournot及Bertrand均衡之效率分析

Optimal Quality Requirements under Cournot and Bertrand Competition

本文以垂直產品差異化模型，探討最適品質管制下Cournot及Bertrand均衡之效率分析。我們發現在差別管制與單一管制下政府對廠商的最適品質管制政策隨廠商的市場競爭型態不同。若政府採差別品質管制，在Bertrand（Cournot）競爭下，應分別要求高、低品質廠商提高產品品質（應分別要求高（低）品質廠商提高（降低）產品品質），縮小（擴大）品質差距。若採取單一品質管制，在Bertrand （Cournot）競爭下，會使兩廠商的產品品質均提高，且低品質廠商生產最低品質標準（應放任廠商自由決定品質）。本文結論除了提供優質農產品品牌標章制訂參考外，也可提供政府對其他產業品質管制政策的參考。 This paper analyzes the optimal uniform and discriminatory quality requirements under Cournot and Bertrand competition when two firms produce high, and low, quality products respectively in a domestic market. We find that under uniform and discriminatory quality requirements, the government's optimal quality requirement depends on the type of competition in which firms engage. When discriminatory quality requirements are adopted, the government should ask both high and low quality firms to raise their quality standard under Bertrand competition and decrease the quality differentiation. However, the government should ask the high quality and low quality firm to raise and lower their quality respectively and increase the quality differentiation under Cournot competition. When uniform quality requirement is adopted, the government should set a quality requirement raising both firms' quality respectively under Bertrand competition, and the low quality firm will produce at the lowest quality standard, while under Cournot competition the government should not set any quality requirement. In addition to premium agricultural products seal, our results also provide useful strategic recommendations for the government's quality policy.

This paper analyzes the optimal uniform and discriminatory quality requirements under Cournot and Bertrand competition when two firms produce high, and low, quality products respectively in a domestic market. We find that under uniform and discriminatory quality requirements, the government's optimal quality requirement depends on the type of competition in which firms engage. When discriminatory quality requirements are adopted, the government should ask both high and low quality firms to raise their quality standard under Bertrand competition and decrease the quality differentiation. However, the government should ask the high quality and low quality firm to raise and lower their quality respectively and increase the quality differentiation under Cournot competition. When uniform quality requirement is adopted, the government should set a quality requirement raising both firms' quality respectively under Bertrand competition, and the low quality firm will produce at the lowest quality standard, while under Cournot competition the government should not set any quality requirement. In addition to premium agricultural products seal, our results also provide useful strategic recommendations for the government's quality policy.