Here some research results:
Admati et al.: Fallacies, Irrelevant Facts, and Myths in the Discussion of Capital Regulation: Why Bank Equity is Not Expensive
We examine the pervasive view that “equity is expensive,” which leads to claims that high capital requirements are costly and would affect credit markets adversely. We find that arguments made to support this view are either fallacious, irrelevant, or very weak. For example, the return on equity contains a risk premium that must go down if banks have more equity. It is thus incorrect to assume that the required return on equity remains fixed as capital requirements increase. It is also incorrect to translate higher taxes paid by banks to a social cost. Policies that subsidize debt and indirectly penalize equity through taxes and implicit guarantees are distortive.Miles et al.: Optimal bank capital
Any desirable public subsidies to banks’ activities should be given directly and not in ways that encourage leverage. Finally, suggestions that high leverage serves a necessary disciplining role are based on inadequate theory lacking empirical support.
We conclude that bank equity is not socially expensive, and that high leverage is not necessary for banks to perform all their socially valuable functions, including lending, taking deposits and issuing money-like securities. To the contrary, better capitalized banks suffer fewer distortions in lending decisions and would perform better. The fact that banks choose high leverage does not imply that this is socially optimal, and, viewed from an ex ante perspective, high leverage may not even be privately optimal for banks.
Setting equity requirements significantly higher than the levels currently proposed would entail large social benefits and minimal, if any, social costs. Approaches based on equity dominate alternatives, including contingent capital. To achieve better capitalization quickly and efficiently and prevent disruption to lending, regulators must actively control equity payouts and issuance. If remaining challenges are addressed, capital regulation can be a powerful tool for enhancing the role of banks in the economy.
This paper reports estimates of the costs and benefits of banks having higher levels of loss-absorbing capital. Measuring those costs requires careful consideration of a wide range of issues about how shifts in funding affect required rates of return and on how costs are influenced by the tax system; it also requires a clear distinction to be drawn between costs to individual institutions (private costs) and overall economic (or social) costs. Without a calculation of the benefits from having banks holding more capital no estimate of costs — however accurate — can tell us what the optimal level of bank capital is. We use empirical evidence on UK banks to assess costs; we use data from shocks to incomes from a wide range of countries over a long period to assess risks to banks and how equity funding (or capital) protects against those risks. We find that the amount of equity capital that is likely to be desirable for banks to hold is very much larger than banks have held in recent years and also higher than targets agreed under the Basel III framework.UPDATE: the government-induced link between bank size and risk taking: here.
