f15_Trading Strategies2_sma_AAPL_Log return_EUR_OLS regress_df highlight_Lagrang_GaussianNB_DNNClass

[T]hey were silly[ˈsɪli]傻瓜，笨蛋 enough to think you can look at the past to predict the future. —The Economist

     This chapter is about the vectorized backtesting of algorithmic trading strategies. The term algorithmic trading strategy is used to describe any type of financial trading strategy that is based on an algorithm designed to take long, short, or neutral positions in financial instruments on its own without human interference. A simple algorithm, such as “altering every five minutes between a long and a neutral position in the stock of Apple, Inc.,” satisfies this definition. For the purposes of this chapter and a bit more technically, an algorithmic trading strategy is represented by some Python code that, giv