A learning rate of 1e-3 is too high and results in very large differences between different runs (Figure ) and much fewer scaffolds of interest are found (Figure ). Figure compares the percentage of valid molecules generated by RL DF(scaffold) for compound 1 when learning rate is 1e-4 and 1e-3. It can be seen that learning rate 1e-4 produces stable output and a high percentage of valid molecules between different runs, while vast variance is observed when the learning rate is 1e-3.