Kenneth R. Ahern
Marshall School of Business
University of Southern California
3670 Trousdale Parkway, HOH 718
Los Angeles, CA 90089
NBER Program Affiliations:
NBER Affiliation: Research Associate
NBER Working Papers and Publications
|February 2018||The Importance of Psychology in Economic Activity: Evidence from Terrorist Attacks|
Terrorist attacks influence economic growth and individual psychology. However, identifying the direct effect of terrorism on economics and psychology is difficult because institutions also change in response to terrorist attacks. This paper controls for institutional responses to terrorist attacks by studying people who live beyond the institutions' borders, but are exposed to the attacks. I find that terrorism leads to declines in trust, subjective well-being, and the importance of creativity and freedom. However, at the macro-level, terrorism leads to increases in economic output and household income. These results are consistent with a growing literature that finds counterintuitive responses to trauma.
|Do Proxies for Informed Trading Measure Informed Trading? Evidence from Illegal Insider Trades|
This paper exploits hand-collected data on illegal insider trades to test whether standard illiquidity measures can detect informed trading. Controlling for unobserved cross-sectional and time-series variation, sampling bias, and strategic timing of insider trades, I find that only absolute order imbalance and the negative autocorrelation of order flows are statistically and economically robust predictors of insider trading. However, this result only holds for short-lived information. When information is long-lived, none of the measures of illiquidity I consider detect informed trading, including bid-ask spreads, Kyle's lambda, and Amihud illiquidity. These results suggest that standard measures of illiquidity have limited applications.