Improved visibility graph fractality with application for the diagnosis of Autism Spectrum Disorder

► Visibility graph (VG) algorithm converts a fractal time series to a scale-free graph. ► We investigate power of scale-freeness of VG (PSVG) for measuring fractality. ► We present an improved and robust PSVG for measurement of fractality of time series. ► We show that the improved PSVG is more robust compared with PSVG. ► We show using improved PSVG results in a more accurate diagnosis of autism.