How do we choose the probability for Russian roulette and at what luminance we should involve it at?

How is p_rr selected?

Is it true that in this case we don't bound the number of bounces?

Is p_rr more optimal when its value is large?

I am also confused what this means. If we didn't do this then wouldn't we have E(x/prr)? How does the expected value not change?

Wouldn't this increase the variance?

How do we decide what prr is

How do we choose the probability for Russian roulette and at what luminance we should involve it at?

How is p_rr selected?

Is it true that in this case we don't bound the number of bounces?

Is p_rr more optimal when its value is large?

I am also confused what this means. If we didn't do this then wouldn't we have E(x/prr)? How does the expected value not change?

Wouldn't this increase the variance?

How do we decide what prr is