Sergei Kovbasyuk

Assistant Professor of Economics at Einaudi Institute for Economics and Finance 

Curriculum Vitae,  skovbasyuk [at]

Research Interests Information Economics, Finance, Contract Theory. 

Working Papers

Information intermediary should not disclose all past records about market participants. Positive and negative records play different roles, and welfare is maximized for short positive records and long but bounded negative records.

The rating agency is paid by the issuer. When payments are non-transparent the equilibrium partition of information into ratings is coarse. When payments are transparent  perfect ratings are feasible and optimal.

An active arbitrageur advertising new information about his targets optimally concentrates his portfolio and advertising on one target. Multiple arbitrageurs also focus on a single target.  This concentration may be inefficient.

We statistically identify key investors that participate in the IPOs with abnormal initial returns in a given year. We show that key investors are persistent and keep participating in IPOs with abnormal initial returns in subsequent years. Key investors appear to be informed, while relationships with underwriters do not seem to explain their performance. 

Credit history in all countries is limited. This can cause endogenous transitions between phases of "lending" and "no lending" to borrowers with empty credit history and generate large fluctuations in aggregate lending in the absence of aggregate shocks.