Why do we have an interbank money market?
IWH Discussion Papers,
The interbank money market plays a key role in the execution of monetary policy. Hence, it is important to know the functioning of this market and the determinants of the interbank money market rate. In this paper, we develop an interbank money market model with a heterogeneous banking sector. We show that besides for balancing daily liquidity fluctuations banks participate in the interbank market because they have different marginal costs of obtaining funds from the central bank. In the euro area, which we refer to, these cost differences occur because banks have different marginal cost of collateral which they need to hold to obtain funds from the central bank. Banks with relatively low marginal costs act as intermediaries between the central bank and banks with relatively high marginal costs. The necessary positive spread between the interbank market rate and the central bank rate is determined by transaction costs and credit risk in the interbank market, total liquidity needs of the banking sector, costs of obtaining funds from the central bank, and the distribution of the latter across banks.
Bank Concentration and Retail Interest Rates
Journal of Banking & Finance,
The recent wave of mergers in the euro area raises the question whether the increase in concentration has offset the increase in competition in European banking through deregulation. We test this question by estimating a simple Cournot model of bank pricing. We construct country and product specific measures of bank concentration and find that for loans and demand deposits increasing concentration may have resulted in less competitive pricing by banks, whereas for savings and time deposits, the model is rejected, suggesting increases in contestability and/or efficiency in these markets. Finally, the paper discusses some implications for tests of the effect of concentration on monetary policy transmission.