Mike Berry is a money manager with $10 billion in assets. Berry reads financial publications to find securities that other money managers recommend. Berry includes these stocks as part of the portfolio but not before he consults with financial advisors to obtain positive information about future security price movements. Berry appears regularly on financial news televised programs as an expert stock picker, where he is celebrated as an investing guru. Berry recently made an investment decision in which he sold equity shares after a 15% decrease in value over the past month. Which behavioral issue least likely influenced his decision