4. Discussion
High variability in the feeding patterns of individual, healthy
pigs was found (Table 1) and is in agreement with the observations
of other researchers (Brown-Brandl et al., 2013; Hessel and Van
den Weghe, 2011).
For the HF RFID system, using two tags per pig, a sensitivity of
88.58% and a specificity of 98.34% could be achieved for a time
window of 9 s. These performance values were based on a minimal
sensitivity of 85%, but with the ROC curve in Fig. 8 the reader can