Although the imagers were in agreement with respect to average entrance
count over the survey, it is clear from Fig. 3 that there is a degree of
disagreement in terms of presence or absence of entrances detected.
Output from the contingency tables (Table 5) show that the visual and
Vayu had agreement on presence or absence of entrances on 83% of
warrens, noting that the Vayu detected entrances where the visual had
not on 27% of warrens (Table 6). The Zenmuse was in poor agreement with
the visual (27%) and Vayu (34%) and it seems the Zenmuse was
particularly prone to detecting warrens that were “false positives”
when compared to visual (85%) and Vayu (100%) (Table 6).
Table 5: Contingency tables for the three pairings of methods (visual vs
Vayu, visual vs Zenmuse and Vayu vs Zenmuse) using classification of
entrance counts as equal to or greater than zero.