Competition, Market Structure, and Bid‐Ask Spreads in Stock Option Markets
研究1986至1997年间竞争和市场结构对股票期权买卖价差的影响，发现多交易所上市和指定做市商制度能缩小价差，但效果随交易量变化。
ABSTRACT This paper examines the effects of competition and market structure on equity option bid‐ask spreads from 1986 to 1997. Options listed on multiple exchanges have narrower spreads than those listed on a single exchange, but the difference diminishes as option volume increases. Option spreads become wider when a competing exchange delists the option. Options traded under a “Designated Primary Marketmaker” (DPM) have narrower quoted spreads than those traded in a traditional open outcry crowd. Effective spreads are found to be slightly narrower under the DPM than in the crowd, but only since 1992, and only on low‐volume options.