Fittings of the (XX-YY)/I intensity ratio of quasar J1744-3116 to determine polarization percentages and polarization position angles. Observations from the four individual spectral windows are presented in separate panels. For each panel, the best fits of polarization percentage, polarization position angle (in the receiver frame; PA), and a constant normalized Stokes Q offsets (Q offset) are provided in the upper left, which are represented by a black curve. For each observed frequency, the errors of fitted quantities were determined by one standard deviation of fittings of 1000 random realizations of noisy data. The gray lines in each panel plot 1 in every 100 of the random realizations.