Table 1 Challenges, advantages, uncertainties and time allotted for each process involved in creation of sampling frame by student user with no prior experience
Process | Time required (h) | Challenges | Advantages | Uncertainties |
|---|---|---|---|---|
Stage 1: Creation of placemarks for all single-standing structures and bomas (Google Earth Pro) | 28.5 | Poor visibility and or contrast | Previous images easily referenced | Potential for structures to be missed |
Time consuming | Easy to mark precise location (independent of occassional mosaicking) | Structures appear and disppear within short time frames so most recent image may not reflect current conditions | ||
Most recent image not available for all areas | No official data necessary to include all potential residences | |||
Cloud cover | Potential for structures to be missed | |||
Bulky interface within Google Earth Pro when editing placemarks | Relatively quick process | Inaccuracy due to nomadism | ||
Stage 2: Compilation of metadata (Microsoft Excel) | 3 | Have to enter each placemark individually | Easily imported to ArcGIS | Potential for data entry error |
Time consuming | ||||
Stage 3: Cleaning sample frame with local expert | 3 | Orienting expert to this technique and aerial and satellite imagery | Elimination of non-household placemarks; robust sample frame | None |