Ultimate ownership and bank competition
研究发现，考虑共同所有权和交叉所有权的广义赫芬达尔指数（GHHI）与银行分支机构的存款利率、维护费及费用门槛显著相关，而传统HHI则无此关联。
Abstract We document substantial time‐series and cross‐sectional variation in branch‐level deposit account interest rates, maintenance fees, and fee thresholds, and examine whether variation in bank concentration helps explain variation in these prices. Herfindahl–Hirschman Index (HHI) alone is not correlated with any of the outcome variables. A “generalized HHI” (GHHI) capturing both common ownership (the degree to which banks are commonly owned by the same investors) and cross‐ownership (the extent to which banks own shares in each other), is strongly correlated with all prices, even when we limit cross‐sectional variation in bank ownership to only that predicted by the growth of index funds.