本文使用44個國家3168家銀行的資料,探討銀行的市場佔有率與其獲利的關係,並簡稱為市場佔有率效果。過去文獻探討這個議題大多以單一國家為樣本,且彼此的結論常不一致,本文的目的是嘗試解決這不一致。我們藉由考慮五個因素變數,即市場結構(銀行集中度)、銀行效率(成本收入比)、法律規定(跨業限制與進入障礙)、政府治理(投資人保護、債權人保護、司法效率性)及經濟發展程度(每人GDP),說明市場佔有率效果的不一致。本文提出一個新論點,即集中的市場結構,較高的銀行效率,良好的政府治理,及良好的經濟發展程度,會增強銀行的市場佔有率的正向效果,或減輕市場佔有率的負向效果,至於法律規定的跨業限制及進入障礙,過去的理論及實證文獻都無定論,故無法推論其對市場佔有率效果的影響。我們的結果支持市場結構、銀行效率、及政府治理的推論,也支持嚴格的進入障礙會增強對市場佔有率的正向效果。至於跨業限制會因為不同產業的跨業限制,而對市場佔有率效果有不同的影響。經濟發展程度對市場佔有率效果的影響則不顯著。
This paper investigates the effects of bank market share on bank profit, which is referred to as the market share effects, using 3168 banks from 44 countries. Previous empirical studies which used single countries to probe the same issue have not reached consensus results. We resolve this puzzle by considering five conditional variables, which are Structure (bank concentration ratio), Efficiency (cost/income), Regulation (restriction on bank activities and entry barriers), Governance (investor protection, creditor protection and law efficiency) and Income (GDP per capita). This study proposes that in countries with concentrated market structure, strong operating efficiency and good governance structure, positive market share effect tends to be enhanced while negative market share effect tends to be mitigated. The opposite is true for countries with less market concentration, poor operating efficiency and weak governance structure. Our evidence also indicates positive market share effect for entry barriers, but not for banking restrictions. Finally, GDP per capita is not associated with market share effect in any significant way.