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Table 1 Challenges, advantages, uncertainties and time allotted for each process involved in creation of sampling frame by student user with no prior experience

From: Using remote, spatial techniques to select a random household sample in a dispersed, semi-nomadic pastoral community: utility for a longitudinal health and demographic surveillance system

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