When we make decisions in life, the outcome normally provides direct feedback on the quality of the decision. For example, when choosing one apple over another because of a blemish turns out to be a good decision because the next customer found the worm ! However, in some domains– like the stock market – the feedback is trickier. In the short-term, the outcome is only a loose signal of decision quality. Engineers refer to such a system as having a low signal to noise ratio.

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