Existing empirical evidence is inconclusive on whether professional investors show sophisticated behavior or not, a question which is at the heart of market efficiency. This ambiguous evidence is mostly based on trading data or laboratory evidence, which each has its limitations. We complement...

This paper presents an online-experiment on overconfidence in the context of financial markets. Our subject pool consists of institutional investors, investment advisors and individual investors, all of them being registered users of a large online platform for market sentiment data. Due to...