Cosmic star formation history. The gray points are taken from Hopkins & Beacom (2006), the dashed line shows their fitting result. The triangular points are from Bouwens et al. (2009, 2011). The open circles are taken from Robertson & Ellis (2012). The filled circles are the SFR derived from GRBs in this work. The dotted line shows the effect SFR calculated from Eq. (19). The thick solid line shows the combination of dashed and dotted lines.