Page 113 - Contributed Paper Session (CPS) - Volume 7

CPS2042 Anna Christine D. et al.
Mesh variability is also another important issue. The variability in the
percentage of area planted in rice inside the meshes increases the CVs of the
estimates of total area planted and the corresponding ratio estimates of total
rice production. One alternative that can be explored is the possibility of using
a different source of satellite data with a stronger discriminatory power for
stratifying the meshes. Future work could also test the interviewer effort
hypothesis to explain whether a mesh was visited and correctly enumerated
by using a logistic regression framework with distance to main road, terrain,
slope, enumerator fixed effects, and other covariates as explanatory factors.
The deviation between official statistics could be due to the presence of
non-sampling errors, subjective intervention, and political leadership at the
local government levels involving subsequent revisions in the administrative
data collection method. In Lao PDR, there is almost a doubling of yield
estimates from official data compared to crop cutting results, which warrants
further investigation into the existing administrative data collection methods.
Despite these challenges, the use of remote sensing and GIS techniques
to obtain rice area and production estimates with relatively high precision is a
major reason for the benefit of this methodology compared to the existing
administrative data collection system for which measures of precision are not
publicly available. With the aid of handheld devices with inbuilt GPS
functionalities, the field teams could navigate to the selected meshes, identify
plot owners, conduct area measurements, and implement crop cutting. The
European Space Agency recently launched the Sentinel-2 satellite which can
provide images at 10 m spatial resolution every 5 days for no charge. As
satellite data gets cheaper and better, there is a higher likelihood for
developing the methodology to adopt area frames.

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