Table 2 Sensitivity (%) of approximation methods versus map-based measures for sample areas in Aberdeenshire and Ayrshire
Current method | |||||||||
|---|---|---|---|---|---|---|---|---|---|
All premises <1 km point distance | All premises <3 km point distance | All premises <5 km point distance | All premises <26 m field distance | All premises <151 m field distance | All premises <1 km field distance | By Voronoi tessellation | By area weighted tessellation | ||
Aberdeenshire | |||||||||
Gold standard | All <15 m | 29.4 | 90.8 | 94.8 | 100.0 | 100.0 | 100.0 | 73.2 | 82.4 |
All <15 m - river | 30.1 | 91.6 | 95.8 | 100.0 | 100.0 | 100.0 | 73.4 | 82.5 | |
All <15 m - road | 29.2 | 92.3 | 94.6 | 100.0 | 100.0 | 100.0 | 73.1 | 83.1 | |
All <15 m - river/road | 30.0 | 93.3 | 95.8 | 100.0 | 100.0 | 100.0 | 73.3 | 83.3 | |
All <15 m - river/road/ditch | 31.2 | 92.7 | 95.4 | 100.0 | 100.0 | 100.0 | 72.5 | 83.5 | |
All <15 m - river/ditch | 32.0 | 90.6 | 95.3 | 100.0 | 100.0 | 100.0 | 72.7 | 82.8 | |
Shared fence | 29.5 | 92.6 | 95.9 | 100.0 | 100.0 | 100.0 | 75.4 | 84.4 | |
Shared fence - river | 29.7 | 92.4 | 95.8 | 100.0 | 100.0 | 100.0 | 74.6 | 83.9 | |
Shared fence - river/ditch | 31.5 | 91.7 | 95.4 | 100.0 | 100.0 | 100.0 | 74.1 | 84.3 | |
Ayrshire | |||||||||
Gold standard | All <15 m | 32.8 | 87.1 | 95.7 | 100.0 | 100.0 | 100.0 | 62.6 | 67.2 |
All <15 m - river | 33.2 | 86.3 | 95.7 | 100.0 | 100.0 | 100.0 | 62.4 | 67.1 | |
All <15 m - road | 32.3 | 88.3 | 96.7 | 100.0 | 100.0 | 100.0 | 64.3 | 69.0 | |
All <15 m - river/road | 32.8 | 87.6 | 96.7 | 100.0 | 100.0 | 100.0 | 64.2 | 69.0 | |
All <15 m - river/road/ditch | 35.5 | 87.9 | 96.8 | 100.0 | 100.0 | 100.0 | 64.9 | 69.0 | |
All <15 m - river/ditch | 35.6 | 86.8 | 95.9 | 100.0 | 100.0 | 100.0 | 63.1 | 67.1 | |
Shared fence | 32.9 | 87.6 | 96.5 | 100.0 | 100.0 | 100.0 | 62.5 | 67.5 | |
Shared fence - river | 33.5 | 87.2 | 96.6 | 100.0 | 100.0 | 100.0 | 63.2 | 68.0 | |
Shared fence - river/ditch | 36.0 | 87.6 | 96.7 | 100.0 | 100.0 | 100.0 | 64.0 | 68.2 | |