If an opportunity arrives at 11:30 with a 75% probablitiy of targeting better than 1% yield, AND a 15% probablity of targeting less than -4% yield, AND a 10% probability of targeting between 1% to -4%, all in less that 1 day time frame, then SELL /STAY OUT the security. Cause the expected gain of the opportunity is -0.10. (0.75 X 1 + 0.10 X -2.5 + 0.15 X -4).