Bid-ask spreads and the avoidance of odd-eighth quotes on Nasdaq: An examination of exchange listings
研究472只从纳斯达克转至纽交所或美交所的股票，发现纳斯达克做市商避免八分之一奇数报价时价差较大且上市后大幅缩小，而使用奇偶报价时价差较小且变化不大，表明避免奇数报价是维持超竞争价差的协调手段。
This paper examines 472 securities that were listed on Nasdaq and moved to the NYSE or Amex. When Nasdaq market makers avoid odd-eighth quotes, bid-ask spreads are large and decline dramatically with exchange listing. When market makers use both odd and even eighths, spreads are smaller and decline only slightly with exchange listing. The large spreads observed when Nasdaq market makers avoid odd-eighths cannot be explained by security-specific characteristics. Instead, the results support the conclusion that the avoidance of odd-eighth quotes is used as a coordination device among Nasdaq market makers to maintain supra-competitive bid-ask spreads.