On Number of Turns in Reduced Random Lattice Paths

Understand

We consider the tree-reduced path of symmetric random walk on $\ZZ^{d}$.

• It is interesting to ask about the number of turns $T_n$ in the reduced path after $n$ steps.
• This question arises from inverting signature for lattice paths.
• We show that, when $n$ is large, the mean and variance of $T_n$ have the same order as $n$, while the second order terms are O(1).