My focus is on large-scale structures of the Universe to understand the properties of dark energy, which occupies approximately 70% of the total energy of the Universe and drives the cosmic acceleration. Recently, I have been working on developing a theoretical model to extract the information of dark energy precisely from the observed gravitational clustering of galaxies. Here at Kavli IPMU, I intend to work on the analysis of the galaxy data from the Baryon Oscillation Spectroscopic Survey (BOSS), which is currently the largest three-dimensional survey of galaxies, considering its possible extensions to the SuMIRe survey at the Subaru Telescope, which involves Kavli IPMU.