Related Securities, Allocation of Attention and Price Discovery: Evidence from NYSE-Listed Non-U.S. Stocks

In this paper we explore how the composition of a market maker's portfolio and allocation of attention across securities in the portfolio affect pricing. We analyze whether more attention devoted to similar securities enables a market maker to extract information relevant to a stock from order flow to related securities and consequently whether it leads to improved price discovery of the stock. We base on the recent literature on allocation of attention in share trading (Corwin and Coughenour, 2008; Boulatov et al., 2009) and define the prominence of a security as the proportion of its dollar volume in the total volume of the specialist portfolio it belongs to. Our empirical tests are focused on New York Stock Exchange specialists and the U.S. share in price discovery of 64 British and French companies cross-listed on the NYSE. We define related securities as stocks from the same country, the same region or other foreign stocks. We find strong evidence that an increase in the prominence of related stocks in the specialist portfolio leads to a higher U.S. share in price discovery of our sample stocks. We interpret our findings as evidence that concentrating market makers in similar stocks reduces information asymmetries and improves the information environment. To support our argument, we show that an increase in the prominence of other foreign stocks in the specialist portfolio significantly reduces the adverse selection component of the bid-ask spread.