Trend of galaxy size (in arcsec and logarithmic scale) with UV absolute magnitude (1500 Å rest frame) at z = 7 and the comparison with some simple power-law relations. The data point at M_UV ~ −20.5 is related to galaxies in the magnitude range 25.6 ≤ J ≤ 26.6, the one at –19.5 is derived using objects with 26.6 ≤ J ≤ 27.6, while the faint bin at –18.5 is the combination of GDS, HUDF, and P12HUDF fields (where the maximum likelihood has been computed restricting to 27.6 ≤ J ≤ 28.6).