Let F=[dfij] denote the weight matrix of G defined by Equation (1):(1)dfij=∑(FAij·wAij)MFCi,eij∈E,0,otherwise, where FAij is called Friendship Action, and may be a Comment, a Like, or any other action from user i on user j on a social network;wAij is the weight of the Action FAij and represents its importance over other actions. Its value is between 0 and 1. For example, for Facebook, a Comment is considered more important than a Like in the proposal. In particular, in the proposal, the weight of a positive Comment is 0.727, while the weight of a Like is 0.273, according to the values obtained from the data shown in the survey . The system may detect positive, negative and neutral Comments using machine learning algorithms ;MFCi is called the Maximal Friendship Coefficient, and represents the maximum sum of weighted actions performed by a user i. Its value is: maxj(∑(FAij·wAij)).