The joint-hypothesis problem casts doubt on the results of market efficiency research. Specifically, it is hard to assess to what extent financial markets reflect economic fundamentals or mispricing. To address this issue, we study price formation in a large virtual asset market where...

We explore if sleep deprivation affects how investors react to relevant news. Using the transition to Daylight Saving Time (DST) in the spring as a disruption to sleeping patterns, we show that investors underreact to a firm’s earnings surprise in the days after the transition to DST. Further,...

Can a short-squeeze incident trigger financial contagion over the entire stock markets? The recent GameStop frenzy provides a unique natural experiment to explore this question. In this study, we examine the static and dynamic return and volatility connectedness among the GameStop stock, the...

This paper improves continuous-time variance swap approximation formulas to derive exact returns on benchmark VIX option portfolios. The new methodology preserves the variance swap interpretation that decomposes returns into realized variance and option implied-variance.We apply this new...

We examine article, author and firm characteristics of investment articles published by non-professional analysts on the social media investment platform Seeking Alpha from 2006 to 2020 leading to visible market value changes. We show that there are differences between articles followed by stock...

We analyze the sentiment of emojis separately to the plain text-expressed sentiment in Reddit posts about meme stocks such as Gamestop during the Covid-19 pandemic. We document that a one-standard deviation change in emoji sentiment magnitude measured as the quantity of positive emoji sentiment...

The purpose of this research is to examine the impact of sentiment derived from news headlines on the direction of stock price changes. The study examines stocks listed on the WIG-banking sub-sector index on the Warsaw Stock Exchange. Two types of data were used: textual and market data. The...

We examine how the market valuation of firms varies on account of characteristics that make them vulnerable to the COVID-19 pandemic across different stages of the crisis. Using plant location data that uniquely identify the vulnerability of firms to operational disruptions, we find that firms...

We document a strong positive initial market reaction to merger announcements from bidders with either large earnings growth or significant earnings decline, relative to those with neutral earnings change, reflecting a U-shaped pattern between bidders’ earnings growth and announcement returns....

Donald Trump's election and his nomination of Scott Pruitt, a climate skeptic, to lead the Environmental Protection Agency drastically downshifted expectations on US climate-change policy. We study firms' stock-price reactions and institutional investors' portfolio adjustments after these...