Lemma 2 Derivation

[gunnxx]

Hi, thanks for the great paper and the reproducible code! I am trying to follow through the derivation and can't quite follow the jump in Lemma B.2. I wonder if you can elaborate more on the "???" part? Thanks in advance!

[ben-eysenbach]

Thanks for the kind words!
We're using $p(h)$ to denote a geometric distribution: $p(h) = (1 - \gamma) \gamma^h$. So, $\sum_h p(t) r_h = (1 - \gamma) \sum_h \gamma^h r_h$. Dividing both sizes by $1 - \gamma$ gives the ``???''

Quick note: I think the second "=" under ``Lemma 2'' in the screenshot above should also have a $\frac{1}{1 - \gamma}$ out in front.

Hope this helps!