MLC classification has successfully analysed original
10 cm resolution images, while the SVM has failed to
do so. Finally, to create a fair comparison, we decided
to reduce and change the spatial resolution of raster
datasets and set rules for aggregating or interpolating
values across the new pixel size to 0.5.
The Kappa coefficient corrects standardized
measures of agreement between two categorical
scores produced by the two rates. Based on Landis
and Koch measurement of observer agreement The
Kappa interpretation of SVM classification gives us
an understanding that agreement is substantial for
values of 0.57, 0.72, and 0.64 and almost perfect
agreement for 0.89. The values for MLC
classification have a similar trend of values where
classification of images 1-4 have values of 0.54, 0.65,
0.71, and 0.69 respectively. In a comparison of the
two classifications, the Kappa coefficient for the
MLC classifier shows higher agreement with
exception of the last-date image where MLC yields
better results.
These results answer the research question,
indicating that the SVM classifier is superior and
gives better performance in classifying urban classes,,
that is refugee settlements in the context of the
research.
When it comes to calculating urbanization, the
research indicates that there has been an exponential
expansion of urban class from 24-12-17 to 24-09-18
from 2.01 km
2
to 5.37 km
2
for SVM. The non-urban
class however reduced from 12.58 km
2
to 9.95 km
2
.
The results found in the research are relevant for
urban sprawl analysis in refugee camp settlement and
Humanitarian actors.
The evolution and increase in the values of
Shannon’s Diversity Index indicate that there is an
increase in urban sprawl and development tends to be
more dispersed over a period of time. This indicates a
rapid increase in urban sprawl. The results of this
index give us the idea of spatiotemporal patterns of
urban growth in Kutupalong Refugee camp.
5 CONCLUSION
We demonstrated the application of remote sensing
classification techniques using 4 UAV images from
different dates to identify and calculate the urban
sprawl in Kutupalong Refugee Camp, Bangladesh
which is under great urban expansion due to the influx
of Rohingya refugees from neighbouring Myanmar.
The Rohingya emergency was one of the biggest
crises in 2017, which has severely affected the
change of the physical landscape of the host
community in Bangladesh.
The research analysed the expansion of the
refugee camp from 2017 to 2018. The objective was
to understand which of the techniques yielded better
results. The research was conducted to understand
and evaluate the performance and agreement of two
different machine learning classifiers – Support
Vector Machine and Maximum Likelihood
Classification.
To answer the research question of which
machine learning classifier technique yields better
performance in urban sprawl classification in
Refugee camp context, both of the classifiers’
performances were similar in terms of overall
accuracy for both of the classes under analysis. In
terms of overall accuracy, the advantage has been
given to SVM classifier as it produced slightly better
results.
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