Table 3.
Wilks lambda and the best sensor selection of different number of sensor taken from different sets (first column: RTIL, second column: conventional films, and third column: all sensors). (F) refers to frequency data and (R) refers to resistance data.
| RTIL | Conventional Films | All Sensors | ||||
|---|---|---|---|---|---|---|
| Sensors | Wilks Λ | Sensors | Wilks Λ | Sensors | Wilks Λ | |
| Frequency Data (4 features) | [Py41][Tf2N](F) | 3.5 × 10−5 | OV-17(F) | 1.6 × 10−4 | [Py41][Tf2N](F) | 1.3 × 10−6 |
| [C4mim][Cl](F) | Siponate DS-10(F) | [C4mim][Cl](F) | ||||
| [C4mim][otf](F) | TCP(F) | [C4mim][otf](F) | ||||
| [C4mim][Tf2N](F) | Apiezon-L(F) | OV-17(F) | ||||
| Resistance Data (4 features) | [Py41][Tf2N](R) | 1.2 × 10−4 | OV-17(R) | 4.2 × 10−3 | [Py41][Tf2N](R) | 6.8 × 10−5 |
| [C4mim][dca](R) | Siponate DS-10(R) | [C6mim][Br](R) | ||||
| [C6mim][Br](R) | TCP(R) | [C6mim][Tf2N](R) | ||||
| [C6mim][Tf2N](R) | PEG-1k(R) | TCP(R) | ||||
| Frequency and Resistance Data (8 features) | [Py41][Tf2N](F&R) | 4.6 × 10−6 | OV-17(F&R) | 9.2 × 10−6 | [Py41][Tf2N](F&R) | 9.8 × 10−8 |
| [P4441][Tf2N](F&R) | Siponate DS-10(F&R) | [C6mim][PF6](F&R) | ||||
| [C6mim][otf](F&R) | TCP(F&R) | TCP(F&R) | ||||
| [C10mim][BF4](F&R) | PEG-1k(F&R) | Apiezon-L(F&R) | ||||
| Frequency (8 features) | [C4mim][otf](F) | 5.6 × 10−6 | [Py41][Tf2N](F) | 1.7× 10−7 | ||
| [Py41][Tf2N](F) | OV-17(F) | |||||
| [C4mim][Cl](F) | [C10mim][BF4](F) | |||||
| [C4mim][Tf2N](F) | [C4mim][otf](F) | |||||
| [C6mim][Br](F) | Apiezon-L(F) | |||||
| [C4mim][Br](F) | [C4mim][Cl](F) | |||||
| [C6mim][Tf2N](F) | [C4mim][Tf2N](F) | |||||
| [N4111][Tf2N](F) | [C6mim][otf](F) | |||||