PMC:4331678 / 14458-15246 JSONTXT

{"project":"2_test","denotations":[{"id":"25707434-11101803-14839074","span":{"begin":648,"end":650},"obj":"11101803"},{"id":"25707434-14990442-14839075","span":{"begin":725,"end":727},"obj":"14990442"}],"text":"where N(i) is the set of proteins that have connections with the i-th protein, 0 ≤ Wij ≤ 1 is the (i, j)-th entry of W , and I is an n × n identity matrix. The first term in Eq. (1) enforces the prediction to be close to the initial annotation of the l proteins, and it is often viewed as the empirical loss term. The minimization of the second term enforces that the functions assigned to an unlabeled protein j are determined by the functions of its connected proteins in W; as such the second term acts as a smoothness loss term [33]. Eq. (1) is motivated by the observation that interacting proteins are more likely to share similar functions [31], and two proteins with similar amino acids often have similar functions [17]. The above equation can be rewritten in matrix notation as:"}