When the disposition effect proves to be rational: Experimental evidence from professional traders.

Area of Science:

• Behavioral Finance
• Financial Markets
• Decision Science

Background:

• The disposition effect, a behavioral finance anomaly, impacts trading performance across investor types.
• Most studies examine the disposition effect in non-mean reverting markets, leaving its behavior in mean-reverting markets under-explored.

Purpose of the Study:

• To investigate how the disposition effect varies in professional traders' decision-making for mean-reverting versus non-mean reverting securities.
• To assess the impact of a simple informational intervention on the disposition effect and trading decisions.

Main Methods:

• A within-subject experiment was conducted with 193 professional traders.
• Traders' decisions were analyzed before and after an informational intervention highlighting the disposition effect.
• The study differentiated between decisions on mean-reverting and non-mean reverting securities.

Main Results:

• Prior to intervention, traders displayed the disposition effect rationally in mean-reverting markets.
• The informational intervention effectively altered the disposition effect and decision-making for both security types.
• The intervention improved returns for non-mean reverting securities but negatively impacted returns for mean-reverting securities.

Conclusions:

• Simple informational interventions can significantly alter decision-making, irrespective of whether the changes are beneficial.
• The effectiveness and impact of such interventions are context-dependent, particularly concerning market properties like mean reversion.
• Understanding these nuances is crucial for optimizing trading strategies and mitigating behavioral biases.