Fig. 4

Selection of the genes trough the LASSO approach and distribution of risk score. (a) Selection of tuning parameter (λ) via 10-fold cross-verification with minimum criteria. The area under curve was plotted versus log (λ). Dotted vertical lines were drawn at the optimal values using the minimum criteria and the 1 standard error of the minimum criteria (the 1-SE criteria). The optimal λ value of 0.033, with log (λ) = − 3.411 was chosen based on minimum criteria. (b) LASSO coefficient profiles of the 186 differentially expressed RNAs. A coefficient profile plot was generated against the log (λ) sequence. Vertical line was drawn at the optimal value where optimal λ led to 23 nonzero coefficients. (c) Distribution of risk score in learning set. (d) Distribution of risk score in verification set