We develop a positive theory of how interest-group competition shapes the organization of Congress and use it to explain campaign contribution patterns in financial services. Since interest groups cannot enforce fee-for-service contracts with legislators, legislators have an incentive to create specialized, standing committees which foster repeated dealing between interests and committee members. The resulting reputational equilibrium supports high contributions and high legislative effort for the interests. Contribution patterns by competing interests in the congressional battle over whether banks can enter new businesses support the theory, which also has implications for term limits and campaign reform.

A number of authors have found that firm size and book-to-market-value capture the cross-sectional variation in average stock returns. More importantly, these variables have been shown to out-perform the CAPM's β coefficient in explaining the cross-section of US stock returns. However, these studies all employ variants of the two-step estimator due to Fama and MacBeth (Fama, E.F., MacBeth, J.D., 1973. Risk, return and equilibrium: Empirical tests. Journal of Political Economy 71, 607–636), which impose implicitly the restriction that idiosyncratic returns are uncorrelated. In this paper we use a one-step estimator due to McElroy et al. (McElroy, M.B., Burmeister, E., Wall, K.D., 1985. Two estimators for the APT model when factors are measured. Economics Letters 19, 271–275) and find a highly significant role for β risk in the UK stock market when we allow for correlation amongst idiosyncratic returns.