After the selection of study area, the map showing halka
boundaries is downloaded and is geo-referenced after which the shapefile of
union councils is overlayed on it and is edited to make new shapefile of halka
boundaries. The map is shown in figure 2.
Figure 2: Map showing the georeferenced basemap and new halka boundary
We have configured freely available open source plugin twitter2qgiswithQGIS. This plugin is still in the experimental state and requires the tweepy package to be installed manually by the user. The installation process of tweepy involves number of steps and requires other packages to be installed first. Initially a .bat file is to be created using the the path for multiple python variables.This file was named as pythonpath.bat and was run using command line (run as administrator). Then setuptools was downloaded and installed using the following command:
Finally after installing setuptools, tweepy package was installed using the following command:
This tool requires twitter access tokens and keys to pull
geo-located tweets. To get these tokens and keys an app was created on
apps.twitter.com and required information was retrieved. Twitter2qgis
is slow and often leave qgis in the not responding state, the tool is under experiment
to be used for downloading geo-tagged tweets data for districts of South
Punjab. The data of the required halka’s available on the Election commission
website is documented in an excel file. The data fields added in the excel file
contain the total number of voters as per the previous elections, the voting
percentage and then the party ranking on the basis of votes gained. The data
collected can be seen in figure 15. To get the value for halka importance the values
for voting percentage were used. All the values were imported into RStudio to
generate a boxplot, outliers were identified and neglected in range calculation,
the new range was then divided into 3 classes and the halka’s having least
voting percentage were ranked 3, medium as 2 and highest were ranked 1.
This
data is then combined with the shapefile on the basis of Halka names to
generate layers. The tweets points shapefile is used as input for point for the
Point Kernel Density tool and radius value of 8 is used to over whole study
area. In order to spatial join the results of the raster generated with the Halka
shapefile, we needed to generate the raster attribute table. The "generate
raster attribute table" requires a single band raster with the integer
type values. Now our raster was single but it had float values so we used raster
calculator to multiply the values with 10000 and then used "int" tool
to generate an integer value raster. The results can be seen in the figure
below:
Figure 3: Showing the results of point kernel density on geo-located tweets
After this "raster to
point" tool was used to generate a points layer which was then joined with
the halka boundaries shapefile using spatial join with mean option. After
spatially join the values, the range was divided into three classes and classes
were named 1,2,3 with 1 showing the high popularity and 3 least popularity. The
results are shown in the figure 4.
An online survey was
conducted to get the second layer of current part popularity. For this, a
simple form was made using google forms and was shared with people through
social platforms like Facebook and the responses were used to get the layer
shown in figure 5. Once the layers are ready, they were converted to raster
layers using polygon to raster
Figure 4: Map showing the popularity of PTI according to online twitter tweets
Figure 5: Map showing the popularity of PTI according to online survey
Figure 6: Map showing the voting percentage (General Elections,2013) wise Halka ranking
Figure 7: Map showing the ranking of PTI according results of General elections 2013
tool. There was no need for
using the reclassify tool as this was already done in the excel sheet. Reclassify
tool is only used for the twitter popularity layer to assign classes 1,2,3.
Then weighted overlay tool is used to assign weights and generate the areas of
high campaign importance. the weight for different layers are shown in the
table below:
Factor Weights
Halka Importance 30%
2013 Ranking 30%
Current Survey Ranking 25%
Twitter Ranking 15%
Table 1: Layers and weights used in weighted overlay tool
Figure 8: Final map highlighting the areas of high, moderate and low campaigns requirement for PTI
After getting the areas of strong,
medium and low campaigns requirement, we have selected one halka of Muzaffargarh,
Punjab due to the availability of the data and to keep our scope limited for
this project. Area is shown in figure below. For the next step we have prepared
layers to highlight the locations of high suitability together arrange an event
for high campaign. For this the data-sets of parcels, roads, higher
Figure 9: Map showing the location of Muzaffargarh
order health facilities,
and built-up area boundaries are used. The landuses of parcels are studied and
all the landuses except vacant land, plots and open spaces are declared as
unsuitable for such events. The agriculture area and orchards are specially
preserved due to their high agriculture value. The figure below shows the query
used to select attribute and add suitability value. After setting suitability
the layer is converted into a raster and can be seen in figure 10.
Figure 10: Map showing parcels divided into suitable and unsuitable classes on the basis of their
current land-use
The attribute value for
urban block name was used to identify parcels that come within the city limit
and the parcels that are in the outskirts, they were merged to get 2 classes
and the layer was then rasterized. This was particularly done to make a layer
that gives consideration to the parking issue that is likely to rise from the
high vehicle movement during such campaigns. The results can be seen in the
figure 11.
Figure 11: Map showing the division of parcels in inner city limits and outskirts
To make the layer for
distance from the health facilities, the health facilities were selected and
converted into the points. Roads network was created and service area polygons
were generated for 1 km and 3 km using the ring option for polygons. The process
can be seen in the figure 12.
Figure 12: Map showing the parcels categorized on the basis of distance from higher order health
facilities
A layer for distance from
primary roads was created by creatingmultiple ring buffer of 1km and 3km around
the primary roads and then the parcels being intersected by the buffer layers
were assigned the respective distance attributes. The layer was then rasterized
and can be seen in the figure 13.
Once all the layers were
ready they were loaded into the weighted overlay tool and output was generated
using equal weights for each layer. The final suitability map is shown in
figure 14. The map shows that area within the built-up area and faraway fromprimary
roads is not suitable for organizing a campaign event.
Figure 13: Map showing parcels categorized on the basis of distance from primary roads
Figure 14: Map showing parcels categorized on the basis of distance from primary roads
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