Identification of a loan supply function: A cross-country test for the existence of a bank lending channel

Using the theoretical predictions of the Bernanke-Blinder [Bernanke, B.S., Blinder, A.S., 1988. Is it money or credit or both or neither? Credit, money, and aggregate demand. American Economic Review 78, 435-459] model, we seek to examine the existence of a bank lending channel through the empirical identification of a loan supply function and to assess the impact of differential bank characteristics on banks' ability to supply loans. To this end, we estimate a loan supply model and test for the restrictions implied by perfect substitutability between loans and bonds in bank portfolios. Estimations are carried out on bank panel data for six OECD countries, the results showing that a bank lending channel is at work in only two of them. Moreover, we find that the relevance of bank characteristics is hardly a decisive factor in the identification of a loan supply function.