Formally-analysis Define a random variable Y for each clause i. If clause i is satisfied,then Yi 1,otherwise Yi 0. Define another random variable Y =i Yi Y has a clear meaning:number of satisfied clauses What's expectation of Y? 10Formally - analysis ◼ Define a random variable 𝑌𝑖 for each clause 𝑖. ❑ If clause 𝑖 is satisfied, then 𝑌𝑖 = 1, otherwise 𝑌𝑖 = 0. ◼ Define another random variable 𝑌 = σ𝑖 𝑌𝑖 ❑ 𝑌 has a clear meaning: number of satisfied clauses ◼ What’s expectation of 𝑌? 10