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STS2319 Lakshman N. R. et al.
                  level  yield  data  for  Thai  Binh.  Results  show  that  while  the  Landsat–MODIS
                  fused data does not necessarily show benefits for paddy rice mapping, it has
                  provided great benefits for crop yield estimation. Only through the fusion data
                  from  Landsat  and  MODIS  can  we  recover  the  peak  growth  trajectory  of
                  vegetation indexes. This information is the most critical input for our current
                  algorithm. Our results also confirm the value of optical data for crop yield
                  estimation  if  the  cloudiness  issue  can  be  alleviated  or  overcome  to  some
                  degree.  We  recognize  that  the  current  fusion  approach  still  has  room  for
                  improvement as has been reviewed by Gao et al. (2015), and as is being further
                  improved by Zhu et al. (2016).
                      One possible issue here is how to best utilize the Landsat–MODIS fused
                  data  and  original  Landsat  data.  More  advanced  smoothing  or  weighted
                  regression  approaches  are  needed  to  deal  with  the  possible  discrepancy
                  between the fused and original data. Meanwhile, emerging new datasets of
                  surface  reflectance,  such  as  Sentinel-2  (20  m  resolution,  16-day  revisiting
                  frequency) and Project for On-Board Autonomy - Vegetation (PROBA-V) from
                  Satellite  Pour  l'Observation  de  la  Terre-  VEGETATION  (SPOT-VGT)  (100  m
                  resolution, 16-day revisiting frequency), can further improve the temporal and
                  spatial  samplings  to  alleviate  cloudiness  issue  in  tropics.  New  fusion
                  algorithms thus should consider multiple sources of data for fusion, instead of
                  only for Landsat and MODIS.

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