  The Parton-Shower algorithm implement in the Pythia generator is applied
multiple times to the same parton-level configuration to estimate the
systematic uncertainty affecting large-radius jet substructure variables
associated with the stochastic nature of the algorithm. Results are presented
in the case of boosted $h\rightarrow b\bar{b}$ and $t\rightarrow bqq$. The code
is publicly available on the repository
https://github.com/rdisipio/ReShower.git
