Peer effects at work: The common stock investments of co-workers

Stock market behavior of individual investors is highly correlated with stock market behavior of their co-workers. For example, a ten percentage point increase in the fraction of co-workers that purchase stocks in a given month is associated with a two percentage point increase in the likelihood of individuals making a purchase. The high correlation exists even after taking controlling for individual socio-demographic characteristics and for time, stock, zip code, and plant fixed effects. Using data on family relations and on residential zip code, we show that the high correlation is not driven by peer effects at the family or zip code level. Moreover, workplace peer effects appear to be strong relative to geographical peer effects

The Sovereign Debt Crisis: Rebalancing or Freezes?

Using high-frequency data we document that episodes of market turmoil in the European sovereign bond market are on average associated with large decreases in trading volume. The response of trading volume to market stress is conditional on transaction costs. Low transaction cost turmoil episodes are associated with volume increases (investors rebalance), while high transaction cost turmoil periods are associated with abnormally low volume (market freezes). We find suggestive evidence of market freezes in response to shocks to the risk bearing capacity of market makers while investor rebalancing is triggered by wealth shocks. Overall, our results show that the recent sovereign debt crisis was not associated with large-scale investor rebalancing