http://repub.eur.nl/res/aut/6543/ List of Publications en http://repub.eur.nl/static-eur/img/logo.png http://repub.eur.nl http://repub.eur.nl/res/pub/35/ 2000-07-07T00:00:00Z In the early transition era in Russia entry barriers for commercial banks were about absent. It resulted in the mushrooming of hundreds of small, poorly-endowed and inexperienced banks. In this paper we address the question whether the claimed benefits of low entry barriers - competition and market dynamics - have resulted. We use a sample of commercial saving banks for the 1994-97 period. We conclude that there were important mobility barriers and that the removal of entry barriers did not lead to intensified competition. http://repub.eur.nl/res/pub/34/ 2000-07-05T00:00:00Z We investigate how sociological argumentation differs from the classical first-order logic. We focus on theories about age dependence of organizational mortality. The overall pattern of argument does not comply with the classical monotonicity principle: adding premises does not overturn conclusions in an argument. The cause of nonmonotonicity is the need to derive conclusions from partial knowledge. We identify meta-principles that appear to guide the observed sociological argumentation patterns, and we formalize a semantics to represent them. This semantics yields a new kind of logical consequence relation. We demonstrate that this new logic can reproduce the results of informal sociological theorizing and lead to new insights. It allows us to unify existing theory fragments and paves the way towards a complete classical theory.