Backtesting is not only a way to check signal accuracy, but also a tool to continually improvement. Data can be used for self adjustment as each stock have a individual behavior. Accuracy and return is not the same. A stock signal may provide low statistical accuracy, but the signals may prove high return in average. Sharp market dips or fundamental changes (earning reports, news updates etc), may force a short term reaction and disturb the signals (Signals may jump quickly from buy to sell, just to return to buy).
|2019-05-09 - 2019-05-17||BUY||12.00|
|2019-03-22 - 2019-05-09||SELL||-6.23|
|2019-03-20 - 2019-03-22||HOLD||0.45|
|2019-03-18 - 2019-03-20||SELL||1.11|
|2019-03-15 - 2019-03-18||HOLD||-2.80|