How (in)efficient is after-hours trading?

@article{Raudys2013HowI,
  title={How (in)efficient is after-hours trading?},
  author={A. Raudys and Esther Mohr and G{\"u}nter Schmidt},
  journal={2013 IEEE Conference on Computational Intelligence for Financial Engineering & Economics (CIFEr)},
  year={2013},
  pages={27-33}
}
In this paper we analyze US stock market after-hours trading. This is a trading outside the regular trading hours of 09:30-16:00. During this time the market is thinly traded and the possibility of price (in)efficiency arises. Price spikes up or down sometimes reaching several percent can be observed. This pattern can be exploited by a simple automated… CONTINUE READING