Matthew and Stephen Fleming are experienced wealth managers in Manitoba. On August 20, 2018, Matthew and Stephen bought 200 shares of Steinbach Gold Inc. and Selkirk Technology Limited. On August 21, 2018, Steinbach put out a press release stating that the company found new gold reserves near the Atitaki Provincial Park. On the same day, Selkirk lost a patent lawsuit worth $1 billion. As a result of these news items, Steinbach’s share price went up by 15% and Selkirk’s share price dipped by 20%. Matthew considered himself as an ace stock picker while Stephen attributed the drop in shares of Selkirk to bad luck. Explain the behavioural finance concept Matthew and Stephen are exhibiting and how this is influencing their decision making.