2.5. Application of machine learning
There were four factors in these experiments, namely, drum speed (rpm), drum surface temperature (°C), residual moisture content (% wb) and lipid yield (mg g-1 of dry biomass). Residual moisture content and lipid yield of corresponding drum speed and drum temperature were mapped to get two features. The training data sets were labelled good (1) or poor (2) based on the lipid yield and residual moisture content (Table 1). Logistic regression with regularisation was used to do the classification of the data gathered through experiments (Dreiseitl & Ohno-Machado, 2002). The following steps mentioned in the Figure 2 were employed.