E_IR/E_opt vs. E_X (left) and L_IR, pk/L_opt, pk vs. L_X, pk (right). E_opt and L_opt are derived either from the analysis of the CoRoT lightcurves (shown as circles) or estimated from the X-ray quantities and the correlation with the optical ones (squares). The remaining symbols are as in Fig. 4. The vertical scale on the right-hand axes indicate the temperature of the black body spectrum, assumed to be responsible for the emission in the optical and IR bands. The results of KS tests comparing the distributions of the optical/IR ratios for flares from Class II and Class III sources are shown in the upper-left corner, both for the higher quality flares (filled symbols) and for all flares. Note that, at least for the higher quality flares, the null probabilities reported indicate that the distributions are significantly different.