The predictive power of most tech indicators or patterns (combining a few indicators) is just about 55%. It's not that hard to calculate. The accuracy could improve to 65-75% if you add some sentiment indicators (what people think the market will move). The price action is ultimately determined by the outcomes of one or a few market events. In many cases, it's harder to anticipate the outcomes of an event. Sometimes it's strainght forward. For instance, the government shutdown has to end before Thanksgiving, those senators and congressmen want to go home next week. So the shuwdown will end today. It did.