# Lecture 11 - *consistent:* given more accurate predictions, the online algorithm should perform close to the optimal offline algorithm, and - *robust:* if the prediction is wrong, the online algorithm performance should be close to the online algorithm without predictions: # Lecture 12 - *Uniform distribution:* All chances are equal: $\text{Pr}(X=k)=\frac{1}{|\text{codom}(X)}$ - *Geometric distribution:* Number of trials until the first success in a sequence of Bernoulli trials: $\text{Pr}(X=k)=(1-p)^{k-1}p$, $\mathbb{E}[X]=\frac{1}{p}$. # Lecture 13 - *Yao’s Principle, informal:* The worst-case performance of the best randomized algorithm is equal to the average performance of the best deterministic algorithm on the worst distribution of the inputs or - If $$\frac{a}{b}$$. In other words the average performance of the best deterministic algorithm is greater than $c$, then $$\frac{\mathcal{E}_{\text{Rand}}\left[\text{Rand}(I)\right]}{\text{Opt}(I)}\geq c$$ - *Coupon Collector’s Problem:* If each box of breakfast cereal contains a coupon, and there are $n$ different coupons, how many boxes do you need to buy in expectation to collect all $n$ coupon? Answer $nH_n$.