Comparison between experiment and theory after averaging over loop length and loop position respectively. Symbols: feature block 1, blue upward-pointing triangles; feature block 2, cyan circles; feature block 3, green downward-pointing triangles; feature block 4, magenta squares; average of all feature blocks, solid black line; prediction, solid red line. a) After averaging over all loop positions, the calculated and experimental hybridization signals as a function of loop length. PM signal is set to 1. b) The dependence of the calculated and experimental hybridization signals on loop position after averaging over all loop lengths. PM signal is set to 1. The experimentally observed hybridization signals are reproduced well by our theory.