This model is equivalent to the IC model. ■lnlC,each edge(u,v)is“used”only once. o b Flip a coin to decide whether the edge“works”. Success with probability p(u,v). Thus we can just flip all the coins at the beginning,and then later follow the outcomes. 11
◼ This model is equivalent to the IC model. ◼ In IC, each edge 𝑢, 𝑣 is “used” only once. ❑ Flip a coin to decide whether the edge “works”. ❑ Success with probability 𝑝 𝑢, 𝑣 . ◼ Thus we can just flip all the coins at the beginning, and then later follow the outcomes. 11
Model 2:LT Linear threshold (LT)model In many situations,multiple and independent sources are needed for an individual to be convinced to adopt some idea. E.g.Seeing 1/3 of your friends using smart phone,you made the decision. 12
Model 2: LT ◼ Linear threshold (LT) model. ◼ In many situations, multiple and independent sources are needed for an individual to be convinced to adopt some idea. ◼ E.g. Seeing 1/3 of your friends using smart phone, you made the decision. 12
■In linear threshold model,.every edge(u,)∈ E has a influence weight w(u,v)E [0,1], o indicating the importance of u on influencing 0. The weights are normalized s.t.Vv,the sum of weights of all incoming edges is at most 1 ∑u:u,weEw(u,)≤1 13
◼ In linear threshold model, every edge 𝑢, 𝑣 ∈ 𝐸 has a influence weight 𝑤 𝑢, 𝑣 ∈ 0,1 , ◼ indicating the importance of 𝑢 on influencing 𝑣. ◼ The weights are normalized s.t. ∀𝑣, the sum of weights of all incoming edges is at most 1 σ𝑢: 𝑢,𝑣 ∈𝐸 𝑤 𝑢, 𝑣 ≤ 1 13