Probability distributions of measured time lags τ_{LSST − grizy} (top-row), relative to reference band LSST-u, and source size R_{LSST − u} (bottom-left), using PyCS (blue), JAVELIN (orange), JAVELIN-Ext (green), and CREAM (purple). True delays and sizes are shown as red lines. In the table, the values represent the 50th, 16th, and 84th percentiles of the respective probability distributions. The last column (Truth) shows the input value of ⟨δt⟩_{LSST − grizy} − ⟨δt⟩_{LSST − u} using Eq. (10). The results from PyCS and JAVELIN are comparable and are 20% smaller than the true size. JAVELIN-Ext leads to even smaller sizes (30% smaller) but CREAM leads to unbiased measurements.