Determinants of bid-asked spreads in the over-the-counter market

Security market regulators, among others, are concerned to know whether or not dealers are natural monopolists. Based on a randomly drawn sample of 314 over-the-counter stocks, the results of this study suggest that while there are economies of scale, they are not on the dealer level. In addition, both systematic and unsystematic risk were tested for association with the transaction costs in this market. The evidence suggests unsystematic risk is related to spread.