Ratios of the observed radio fluxes to the modeled radio fluxes for all the quasi-simultaneous radio–X-ray observations of the four outbursts. Each outburst is represented using a different symbol (see legend). In blue are shown the rising phases and in red the decaying phases. The modeled radio fluxes were obtained using Eq. (2). The parameters are (α = −0.67, β = 0.94) for the rising phases and (α = −0.15, β = 0.9) for the decaying phases. Top panel: used for all outbursts. Bottom panel: different used for each phase of the outbursts. All values of used are reported in Table 3. The horizontal dashed lines represent a 20% error margin (ratio of 0.8 and 1.2, respectively).