Soft X-ray vs. UV flare relationships. Left: total transition region emission E_TR observed during the UVCS exposures corresponding to the peak O vi emission (i.e., L_TR times the exposure time), plotted against the variation in GOES X-ray luminosity ΔL_X between the UVCS exposures corresponding to the peak O vi emission and the following exposure. Right: transition region luminosity L_TR during the peak UVCS exposure plotted against the GOES X-ray luminosity L_X at the peak of the L_TR. Also shown are the least-square linear fits to the log-log data (solid line), i.e., the best fit power-law regressions, together with the respective 95% confidence intervals (dotted lines).