AUC, area under the curve; FEV1: forced expiratory volume in one second; FVC, Forced vital capacity; FEF25%, forced expiratory flow (FEF) at 25% of forced vital capacity; FEF50%, FEF at 50% of FVC; FEF75%, FEF at 75% of FVC; FEF25%-75%, FEF at 25% to 75% of FVC; R5, total airway resistance at 5 Hz; R20, central airway resistance at 20 Hz; R5-R20, peripheral airway resistance as the difference between 5 and 20 Hz; X5, reactance at 5 Hz; Fres, resonant frequency; FENO, fractional exhaled nitric oxide; Eos: eosinophils; PLT: platelet;
AUC (1st), take the first part as the test set and the rest as the training set, then compute AUC; Average AUC, the average AUC of five different cross-validation model; Whole Model, use all of the data set to compute AUC; Error Rate, Error Rate equals to abs (Average AUC – Whole Model AUC) / (Whole Model AUC).
We command that we calculated the four decimal places of AUC, and we kept three decimal places of AUC on the table 4. We use Tabular data which is three decimals to compute Error Rate.
Table 2. Accurate classification rates in 80/20 split-sample cross validation of prediction models.