(a)
(b)
Figure 4: Accuracy profile for NIR quantitative methods. (a) Quantification of cryptotanshinone content; (b) quantification of tanshinoneIIA content. The medium blue dashed lines are the 66.7% β-content, 90% γ-confidence tolerance intervals and the red lines are the acceptance limits (±20%); the black point at each concentration level represents the relative bias for each predictive value.