In this exercise, we will gain hands-on experience on how to delineate homogeneous region by using geographically referenced multivariate data. There are two major analysis, namely: 1. hierarchical cluster analysis; and 2. spatially constrained cluster analysis.
By the end of this hands-on exercise, we will able: - to convert GIS polygon data into R’s simple feature data.frame by using appropriate functions of sf package of R; - to convert simple feature data.frame into R’s SpatialPolygonDataFrame object by using appropriate sf of package of R; - to perform custer analysis by using hclust() of Base R; - to perform spatially constrained cluster analysis using skater() of Base R; and - to visualise the analysis output by using ggplot2 and tmap package.
In geobusiness and spatial policy, it is a common practice to delineate the market or planning area into homogeneous regions by using multivariate data. In this hands-on exercise, we are interested to delineate Shan State, Myanmar into homogeneous regions by using multiple Information and Communication technology (ICT) measures, namely: Radio, Television, Land line phone, Mobile phone, Computer, and Internet at home.
Two data sets will be used in this study. They are: 1. Myanmar Township Boundary Data (i.e. myanmar_township_boundaries) : This is a GIS data in ESRI shapefile format. It consists of township bondary information of Myanmar. The spatial data are casptured in polygon features. 2. Shan-ICT.csv: This is an extract of The 2014 Myanmar Population and Housing Census Myanmar at the township level. Both data sets are download from Myanmar Information Management Unit (MIMU)
Before we get started, it is important for us to install the necessary R packages into R and launch these R packages into R environment.
The R packages needed for this exercise are as follows: - Spatial data handling: sf, and spdep - Geospatial analysis package: ClustGeo - Attribute data handling: tidyverse, especially readr, ggplot2 and dplyr - Choropleth mapping: tmap
packages = c('rgdal', 'spdep', 'ClustGeo', 'tmap', 'sf', 'ggpubr', 'cluster', 'heatmaply', 'corrplot', 'tidyverse', 'psych')
for (p in packages){
if(!require(p, character.only = T)){
install.packages(p)
}
library(p,character.only = T)
}
## Loading required package: rgdal
## Loading required package: sp
## rgdal: version: 1.4-8, (SVN revision 845)
## Geospatial Data Abstraction Library extensions to R successfully loaded
## Loaded GDAL runtime: GDAL 2.4.2, released 2019/06/28
## Path to GDAL shared files: /Library/Frameworks/R.framework/Versions/3.6/Resources/library/rgdal/gdal
## GDAL binary built with GEOS: FALSE
## Loaded PROJ.4 runtime: Rel. 5.2.0, September 15th, 2018, [PJ_VERSION: 520]
## Path to PROJ.4 shared files: /Library/Frameworks/R.framework/Versions/3.6/Resources/library/rgdal/proj
## Linking to sp version: 1.3-2
## Loading required package: spdep
## Loading required package: spData
## To access larger datasets in this package, install the spDataLarge
## package with: `install.packages('spDataLarge',
## repos='https://nowosad.github.io/drat/', type='source')`
## Loading required package: sf
## Linking to GEOS 3.7.2, GDAL 2.4.2, PROJ 5.2.0
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##
## Attaching package: 'plotly'
## The following object is masked from 'package:ggplot2':
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## ======================
## Welcome to heatmaply version 1.1.0
##
## Type citation('heatmaply') for how to cite the package.
## Type ?heatmaply for the main documentation.
##
## The github page is: https://github.com/talgalili/heatmaply/
## Please submit your suggestions and bug-reports at: https://github.com/talgalili/heatmaply/issues
## Or contact: <tal.galili@gmail.com>
## ======================
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With tidyverse, we do not have to install readr, ggplot2 and dplyr packages seperately. In fact, tidyverse also installes other very useful R packages such as tidyr.
In this section, you will import Myanmar Township Boundary GIS data and its associated attrbiute table into R environment.
The Myanmar Township Boundary GIS data is in ESRI shapefile format. It will be imported into R environment by using the st_read() function of sf.
shan_sf <- st_read(dsn = "data/geospatial", layer = "myanmar_township_boundaries") %>%
filter(ST %in% c("Shan (East)", "Shan (North)", "Shan (South)"))
## Reading layer `myanmar_township_boundaries' from data source `/Users/theodora/Desktop/IS415/Lesson 10/data/geospatial' using driver `ESRI Shapefile'
## Simple feature collection with 330 features and 14 fields
## geometry type: MULTIPOLYGON
## dimension: XY
## bbox: xmin: 92.17275 ymin: 9.671252 xmax: 101.1699 ymax: 28.54554
## CRS: 4326
The imported township boundary object is called shan_sf. It is saved in simple feature data.frame format. We can view the content of the newly created shan_sf simple features data.frame by using the code chun below.
shan_sf
## Simple feature collection with 55 features and 14 fields
## geometry type: MULTIPOLYGON
## dimension: XY
## bbox: xmin: 96.15107 ymin: 19.29932 xmax: 101.1699 ymax: 24.15907
## CRS: 4326
## First 10 features:
## OBJECTID ST ST_PCODE DT DT_PCODE TS TS_PCODE
## 1 163 Shan (North) MMR015 Mongmit MMR015D008 Mongmit MMR015017
## 2 203 Shan (South) MMR014 Taunggyi MMR014D001 Pindaya MMR014006
## 3 240 Shan (South) MMR014 Taunggyi MMR014D001 Ywangan MMR014007
## 4 106 Shan (South) MMR014 Taunggyi MMR014D001 Pinlaung MMR014009
## 5 72 Shan (North) MMR015 Mongmit MMR015D008 Mabein MMR015018
## 6 40 Shan (South) MMR014 Taunggyi MMR014D001 Kalaw MMR014005
## 7 194 Shan (South) MMR014 Taunggyi MMR014D001 Pekon MMR014010
## 8 159 Shan (South) MMR014 Taunggyi MMR014D001 Lawksawk MMR014008
## 9 61 Shan (North) MMR015 Kyaukme MMR015D003 Nawnghkio MMR015013
## 10 124 Shan (North) MMR015 Kyaukme MMR015D003 Kyaukme MMR015012
## ST_2 LABEL2 SELF_ADMIN ST_RG T_NAME_WIN
## 1 Shan State (North) Mongmit\n61072 <NA> State rdk;rdwf
## 2 Shan State (South) Pindaya\n77769 Danu State yif;w,
## 3 Shan State (South) Ywangan\n76933 Danu State &GmiH
## 4 Shan State (South) Pinlaung\n162537 Pa-O State yifavmif;
## 5 Shan State (North) Mabein\n35718 <NA> State rbdrf;
## 6 Shan State (South) Kalaw\n163138 <NA> State uavm
## 7 Shan State (South) Pekon\n94226 <NA> State z,fcHk
## 8 Shan State (South) Lawksawk <NA> State &yfapmuf
## 9 Shan State (North) Nawnghkio\n128357 <NA> State aemifcsdK
## 10 Shan State (North) Kyaukme\n172874 <NA> State ausmufrJ
## T_NAME_M3 AREA geometry
## 1 မိုးမိတ\u103a 2703.611 MULTIPOLYGON (((96.96001 23...
## 2 ပင\u103aးတယ 629.025 MULTIPOLYGON (((96.7731 21....
## 3 ရ\u103dာငံ 2984.377 MULTIPOLYGON (((96.78483 21...
## 4 ပင\u103aလောင\u103aး 3396.963 MULTIPOLYGON (((96.49518 20...
## 5 မဘိမ\u103aး 5034.413 MULTIPOLYGON (((96.66306 24...
## 6 ကလော 1456.624 MULTIPOLYGON (((96.49518 20...
## 7 ဖယ\u103aခုံ 2073.513 MULTIPOLYGON (((97.14738 19...
## 8 ရပ\u103aစောက\u103a 5145.659 MULTIPOLYGON (((96.94981 22...
## 9 နောင\u103aခ\u103bို 3271.537 MULTIPOLYGON (((96.75648 22...
## 10 က\u103bောက\u103aမဲ 3920.869 MULTIPOLYGON (((96.95498 22...
Notice that sf.data.frame is conformed to Hardy Wickham’s tidy framework.
Since shan_sf is conformed to tidy framework, we can also glimpse() to reveal the data type of it’s fields.
glimpse(shan_sf)
## Observations: 55
## Variables: 15
## $ OBJECTID <dbl> 163, 203, 240, 106, 72, 40, 194, 159, 61, 124, 71, 155, 10…
## $ ST <fct> Shan (North), Shan (South), Shan (South), Shan (South), Sh…
## $ ST_PCODE <fct> MMR015, MMR014, MMR014, MMR014, MMR015, MMR014, MMR014, MM…
## $ DT <fct> Mongmit, Taunggyi, Taunggyi, Taunggyi, Mongmit, Taunggyi, …
## $ DT_PCODE <fct> MMR015D008, MMR014D001, MMR014D001, MMR014D001, MMR015D008…
## $ TS <fct> Mongmit, Pindaya, Ywangan, Pinlaung, Mabein, Kalaw, Pekon,…
## $ TS_PCODE <fct> MMR015017, MMR014006, MMR014007, MMR014009, MMR015018, MMR…
## $ ST_2 <fct> Shan State (North), Shan State (South), Shan State (South)…
## $ LABEL2 <fct> Mongmit
## 61072, Pindaya
## 77769, Ywangan
## 76933, Pinlaung
## 1625…
## $ SELF_ADMIN <fct> NA, Danu, Danu, Pa-O, NA, NA, NA, NA, NA, NA, NA, NA, NA, …
## $ ST_RG <fct> State, State, State, State, State, State, State, State, St…
## $ T_NAME_WIN <fct> "rdk;rdwf", "yif;w,", "&GmiH", "yifavmif;", "rbdrf;", "uav…
## $ T_NAME_M3 <fct> မိုးမိတ်, ပင်းတယ, ရွာငံ, ပင်လောင်း, မဘိမ်း, ကလော, ဖယ်ခုံ, …
## $ AREA <dbl> 2703.611, 629.025, 2984.377, 3396.963, 5034.413, 1456.624,…
## $ geometry <MULTIPOLYGON [°]> MULTIPOLYGON (((96.96001 23..., MULTIPOLYGON …
The csv file will be import using read_csv function of readr package.
The code chunks used are shown below:
ict <- read_csv ("data/aspatial/Shan-ICT.csv")
## Parsed with column specification:
## cols(
## `District Pcode` = col_character(),
## `District Name` = col_character(),
## `Township Pcode` = col_character(),
## `Township Name` = col_character(),
## `Total households` = col_double(),
## Radio = col_double(),
## Television = col_double(),
## `Land line phone` = col_double(),
## `Mobile phone` = col_double(),
## Computer = col_double(),
## `Internet at home` = col_double()
## )
The imported InfoComm variables extract of The 2014 Myanmar Population and Housing Census Myanmar attribute data set is called ict. It is saved in R’s * tibble data.frame* format.
The code chunk below reveal the summary statistics of ict data.frame.
summary(ict)
## District Pcode District Name Township Pcode Township Name
## Length:55 Length:55 Length:55 Length:55
## Class :character Class :character Class :character Class :character
## Mode :character Mode :character Mode :character Mode :character
##
##
##
## Total households Radio Television Land line phone
## Min. : 3318 Min. : 115 Min. : 728 Min. : 20.0
## 1st Qu.: 8711 1st Qu.: 1260 1st Qu.: 3744 1st Qu.: 266.5
## Median :13685 Median : 2497 Median : 6117 Median : 695.0
## Mean :18369 Mean : 4487 Mean :10183 Mean : 929.9
## 3rd Qu.:23471 3rd Qu.: 6192 3rd Qu.:13906 3rd Qu.:1082.5
## Max. :82604 Max. :30176 Max. :62388 Max. :6736.0
## Mobile phone Computer Internet at home
## Min. : 150 Min. : 20.0 Min. : 8.0
## 1st Qu.: 2037 1st Qu.: 121.0 1st Qu.: 88.0
## Median : 3559 Median : 244.0 Median : 316.0
## Mean : 6470 Mean : 575.5 Mean : 760.2
## 3rd Qu.: 7177 3rd Qu.: 507.0 3rd Qu.: 630.5
## Max. :48461 Max. :6705.0 Max. :9746.0
The unit of measurement of the values are number of household. Using these values directly will be bais by the underlying total number of households. In general, the townships with relatively higher total number of households will also have higher number of households owning radio, TV, etc.
In order to overcome this problem, we will derive the penetration rate of each ICT variable by using the code chunk below.
ict_derived <- ict %>%
mutate(`RADIO_PR` = `Radio`/`Total households`*1000) %>%
mutate(`TV_PR` = `Television`/`Total households`*1000) %>%
mutate(`LLPHONE_PR` = `Land line phone`/`Total households`*1000) %>%
mutate(`MPHONE_PR` = `Mobile phone`/`Total households`*1000) %>%
mutate(`COMPUTER_PR` = `Computer`/`Total households`*1000) %>%
mutate(`INTERNET_PR` = `Internet at home`/`Total households`*1000) %>%
rename(`DT_PCODE` =`District Pcode`,`DT`=`District Name`,
`TS_PCODE`=`Township Pcode`, `TS`=`Township Name`,
`TT_HOUSEHOLDS`=`Total households`,
`RADIO`=`Radio`, `TV`=`Television`,
`LLPHONE`=`Land line phone`, `MPHONE`=`Mobile phone`,
`COMPUTER`=`Computer`, `INTERNET`=`Internet at home`)
Let us review the summary statistics of the newly derived penetration rates using the code chunk below.
summary(ict_derived)
## DT_PCODE DT TS_PCODE TS
## Length:55 Length:55 Length:55 Length:55
## Class :character Class :character Class :character Class :character
## Mode :character Mode :character Mode :character Mode :character
##
##
##
## TT_HOUSEHOLDS RADIO TV LLPHONE
## Min. : 3318 Min. : 115 Min. : 728 Min. : 20.0
## 1st Qu.: 8711 1st Qu.: 1260 1st Qu.: 3744 1st Qu.: 266.5
## Median :13685 Median : 2497 Median : 6117 Median : 695.0
## Mean :18369 Mean : 4487 Mean :10183 Mean : 929.9
## 3rd Qu.:23471 3rd Qu.: 6192 3rd Qu.:13906 3rd Qu.:1082.5
## Max. :82604 Max. :30176 Max. :62388 Max. :6736.0
## MPHONE COMPUTER INTERNET RADIO_PR
## Min. : 150 Min. : 20.0 Min. : 8.0 Min. : 21.05
## 1st Qu.: 2037 1st Qu.: 121.0 1st Qu.: 88.0 1st Qu.:138.95
## Median : 3559 Median : 244.0 Median : 316.0 Median :210.95
## Mean : 6470 Mean : 575.5 Mean : 760.2 Mean :215.68
## 3rd Qu.: 7177 3rd Qu.: 507.0 3rd Qu.: 630.5 3rd Qu.:268.07
## Max. :48461 Max. :6705.0 Max. :9746.0 Max. :484.52
## TV_PR LLPHONE_PR MPHONE_PR COMPUTER_PR
## Min. :116.0 Min. : 2.78 Min. : 36.42 Min. : 3.278
## 1st Qu.:450.2 1st Qu.: 22.84 1st Qu.:190.14 1st Qu.:11.832
## Median :517.2 Median : 37.59 Median :305.27 Median :18.970
## Mean :509.5 Mean : 51.09 Mean :314.05 Mean :24.393
## 3rd Qu.:606.4 3rd Qu.: 69.72 3rd Qu.:428.43 3rd Qu.:29.897
## Max. :842.5 Max. :181.49 Max. :735.43 Max. :92.402
## INTERNET_PR
## Min. : 1.041
## 1st Qu.: 8.617
## Median : 22.829
## Mean : 30.644
## 3rd Qu.: 41.281
## Max. :117.985
We can plot the distribution of the variables (i.e. Number of households with radio) by using appropriate Exploratory Data Analysis (EDA) as shown in the code chunk below.
Histogram is useful to identify the overall distribution of the data values (i.e. left skew, right skew or normal distribution)
ggplot(data=ict_derived, aes(x=`RADIO`)) +
geom_histogram(bins=20, color="black", fill="light blue")
Boxplot is useful to detect if there are outliers.
ggplot(data=ict_derived, aes(x=`RADIO`)) +
geom_boxplot(color="black", fill="light blue")
Next, we will also plotting the distribution of the newly derived variables (i.e. Radio penetration rate) by using the code chunk below.
ggplot(data=ict_derived, aes(x=`RADIO_PR`)) +
geom_histogram(bins=20, color="black", fill="light blue")
ggplot(data=ict_derived, aes(x=`RADIO_PR`)) +
geom_boxplot(color="black", fill="light blue")
The code chunks below are used to create the data visualisation. They consist of two main parts. First, we will create the individual histograms using the code chunk below.
radio <- ggplot(data=ict_derived,
aes(x= `RADIO_PR`)) +
geom_histogram(bins=20,
color="black",
fill="light blue")
tv <- ggplot(data=ict_derived,
aes(x= `TV_PR`)) +
geom_histogram(bins=20,
color="black",
fill="light blue")
llphone <- ggplot(data=ict_derived,
aes(x= `LLPHONE_PR`)) +
geom_histogram(bins=20,
color="black",
fill="light blue")
mphone <- ggplot(data=ict_derived,
aes(x= `MPHONE_PR`)) +
geom_histogram(bins=20,
color="black",
fill="light blue")
computer <- ggplot(data=ict_derived,
aes(x= `COMPUTER_PR`)) +
geom_histogram(bins=20,
color="black",
fill="light blue")
internet <- ggplot(data=ict_derived,
aes(x= `INTERNET_PR`)) +
geom_histogram(bins=20,
color="black",
fill="light blue")
Use the ggarange() function of ggpubr package is used to group these histograms together.
ggarrange(radio, tv, llphone, mphone, computer, internet,
ncol = 3,
nrow = 2)
Before we can prepare the choropleth map, we need to combine both the geospatial data object (i.e. shan_sf) and aspatial data.frame object (i.e. ict_derived) into one. This will be performed by using the left_join function of dplyr package. The shan_sf simple feature data.frame will be used as the base data object and the ict_derived data.frame will be used as the join table.
The code chunks below is used to perform the task. The unique identifier used to join both data objects is TS_PCODE.
shan_sf <- left_join(shan_sf, ict_derived, by=c("TS_PCODE"="TS_PCODE"))
## Warning: Column `TS_PCODE` joining factor and character vector, coercing into
## character vector
The message above shows that TS_CODE field is the common field used to perform the left-join.
It is important to note that there is no new output data been created. Instead, the data fields from ict_derived data frame are now updated into the data frame of shan_sf.
To have a quick look at the distribution of Radio penetration rate of Shan State at township level, a choropleth map will be prepared.
The code chunks below are used to prepare the choropleth by using the qtm() function of tmap package
qtm(shan_sf, "RADIO_PR")
In order to reveal that the distribution shown in the choropleth map above are bias to the underlying total number of households at the townships, we will create two choropleth maps, one for the total number of households (i.e. TT_HOUSEHOLDS.map) and one for the total number of household with Radio (RADIO.map) by using the code chunk below.
TT_HOUSEHOLDS.map <- tm_shape(shan_sf) +
tm_fill(col = "TT_HOUSEHOLDS",
n = 5,
style = "jenks",
title = "Total households") +
tm_borders(alpha = 0.5)
RADIO.map <- tm_shape(shan_sf) +
tm_fill(col = "RADIO",
n = 5,
style = "jenks",
title = "Number Radio ") +
tm_borders(alpha = 0.5)
tmap_arrange(TT_HOUSEHOLDS.map, RADIO.map,
asp=NA, ncol=2)
Notice that the choropleth maps above clearly show that townships with relatively larger number ot households are also showing relatively higher number of radio ownership.
Now let us plot the choropleth maps showing the dsitribution of total number of households and Radio penetration rate by using the code chunk below.
tm_shape(shan_sf) +
tm_polygons(c("TT_HOUSEHOLDS", "RADIO_PR"),
style="jenks") +
tm_facets(sync = TRUE, ncol = 2) +
tm_legend(legend.position = c("right", "bottom"))+
tm_layout(outer.margins=0, asp=0)
Before we perform cluster analysis, it is important for us to endure that the input variables use are not highly correlated.
In this section, you will learn how to use corrplot.mixed() function of corrplot package to visualise and analyse the correlation of the input variables.
cluster_vars.cor = cor(ict_derived[,12:17])
corrplot.mixed(cluster_vars.cor,
lower = "ellipse",
upper = "number",
tl.pos = "lt",
diag = "l",
tl.col = "black")
The correlation plot above shows that COMPUTER_PR and INTERNET_PR are highly correlated. This suggest that only one of them should be used in the cluster analysis instead of both.
The code chunk below will be used to extract the clustering variables from the shan_sf simple feature object into data.frame
cluster_vars <- shan_sf %>%
st_set_geometry(NULL) %>%
select("TS.x", "RADIO_PR", "TV_PR", "LLPHONE_PR", "MPHONE_PR", "COMPUTER_PR")
cluster_vars
## TS.x RADIO_PR TV_PR LLPHONE_PR MPHONE_PR COMPUTER_PR
## 1 Mongmit 286.18517 554.1313 35.306182 260.69440 12.159391
## 2 Pindaya 417.46466 505.1300 19.835841 162.39170 12.881897
## 3 Ywangan 484.52147 260.5734 11.935906 120.28559 4.414650
## 4 Pinlaung 231.64994 541.7189 28.544542 249.49028 13.762547
## 5 Mabein 449.49027 708.6423 72.752549 392.60890 16.450417
## 6 Kalaw 280.76244 611.6204 42.064778 408.79514 29.631601
## 7 Pekon 318.61183 535.8494 39.832703 214.84764 18.970325
## 8 Lawksawk 387.10175 630.0035 31.513657 320.56863 21.766768
## 9 Nawnghkio 349.33590 547.9456 38.449603 323.02011 15.764647
## 10 Kyaukme 210.95485 601.1773 39.582672 372.49304 30.947094
## 11 Muse 175.88008 842.5317 139.551634 712.92878 91.293779
## 12 Laihka 153.35609 590.5575 65.529010 261.43345 27.758817
## 13 Mongnai 182.51928 515.9062 5.141388 267.51285 28.277635
## 14 Mawkmai 97.44231 234.5010 2.780095 36.41924 7.784265
## 15 Kutkai 238.71578 474.0161 62.897378 264.62088 21.070884
## 16 Mongton 193.51808 388.4453 25.129169 290.51198 21.841240
## 17 Mongyai 168.44238 364.2707 20.333133 135.12905 9.378752
## 18 Mongkaing 156.74749 116.0299 6.000490 50.75925 8.388440
## 19 Lashio 235.73893 680.7891 66.685148 463.83909 60.216842
## 20 Mongpan 228.74008 517.2477 21.582734 437.74211 46.485888
## 21 Matman 244.12297 219.4093 8.438819 45.20796 6.027728
## 22 Tachileik 363.35354 759.4214 59.751756 735.43090 92.401937
## 23 Narphan 75.27012 210.0886 42.187690 305.26891 3.277892
## 24 Mongkhet 79.37695 313.3956 29.034268 114.64174 6.853583
## 25 Hsipaw 198.12167 475.8613 32.316784 269.08669 14.588719
## 26 Monghsat 107.67490 460.1169 34.508769 189.51537 22.817273
## 27 Mongmao 120.05744 512.6855 85.495452 424.98803 11.297271
## 28 Nansang 203.99724 585.6969 37.586810 314.63712 30.641998
## 29 Laukkaing 53.26400 778.5117 134.354578 716.74513 35.556180
## 30 Pangsang 97.44765 490.3358 62.569694 440.83757 50.427456
## 31 Namtu 240.01374 630.6159 35.220342 105.05970 19.929559
## 32 Monghpyak 405.02839 503.3252 42.497972 381.83293 25.141930
## 33 Konkyan 21.05456 287.0743 169.351886 316.73380 10.801904
## 34 Mongping 161.90476 330.8817 24.611033 190.75908 11.598303
## 35 Hopong 205.55645 455.8395 32.311550 209.96441 14.477515
## 36 Nyaungshwe 323.70878 554.4870 18.998921 351.19857 15.691701
## 37 Hsihseng 246.77306 505.5689 31.796405 145.09780 9.917305
## 38 Mongla 82.18126 673.1951 86.981567 555.10753 62.596006
## 39 Hseni 257.32235 628.8310 44.825537 431.87028 19.696069
## 40 Kunlong 121.92071 589.7806 181.485758 237.58661 20.785219
## 41 Hopang 127.60443 556.8737 81.746586 487.68817 24.523976
## 42 Namhkan 134.98623 653.5462 91.796237 596.48877 30.162955
## 43 Kengtung 267.50939 637.7874 63.203895 487.32989 47.542234
## 44 Langkho 227.46781 587.1483 74.391989 403.91035 32.308059
## 45 Monghsu 235.95261 464.9495 11.629171 231.06184 12.389958
## 46 Taunggyi 365.30919 755.2661 81.545688 586.66651 81.170403
## 47 Pangwaun 76.24025 366.7406 28.992770 518.14733 6.013315
## 48 Kyethi 268.62150 447.1408 22.357039 89.65285 12.807550
## 49 Loilen 142.92267 552.6099 21.649390 253.00431 32.015411
## 50 Manton 194.32513 188.3379 8.069764 54.79630 3.644410
## 51 Mongyang 71.74622 569.3250 113.944066 469.01868 12.847119
## 52 Kunhing 161.48796 473.0853 73.085339 340.48140 26.039387
## 53 Mongyawng 278.08501 739.2953 121.978196 324.06383 15.326276
## 54 Tangyan 223.86318 453.2753 22.594047 105.23021 12.065335
## 55 Namhsan 230.83668 390.5005 23.090976 97.77128 8.987943
Notice that the final clustering variables list does not include variable INTERNET_PR because it is highly correlated with variable COMPUTER_PR.
Next, we need to change the rows by township name instead of row number by using the code chunk below
row.names(cluster_vars) <- cluster_vars$"TS.x"
cluster_vars
## TS.x RADIO_PR TV_PR LLPHONE_PR MPHONE_PR COMPUTER_PR
## Mongmit Mongmit 286.18517 554.1313 35.306182 260.69440 12.159391
## Pindaya Pindaya 417.46466 505.1300 19.835841 162.39170 12.881897
## Ywangan Ywangan 484.52147 260.5734 11.935906 120.28559 4.414650
## Pinlaung Pinlaung 231.64994 541.7189 28.544542 249.49028 13.762547
## Mabein Mabein 449.49027 708.6423 72.752549 392.60890 16.450417
## Kalaw Kalaw 280.76244 611.6204 42.064778 408.79514 29.631601
## Pekon Pekon 318.61183 535.8494 39.832703 214.84764 18.970325
## Lawksawk Lawksawk 387.10175 630.0035 31.513657 320.56863 21.766768
## Nawnghkio Nawnghkio 349.33590 547.9456 38.449603 323.02011 15.764647
## Kyaukme Kyaukme 210.95485 601.1773 39.582672 372.49304 30.947094
## Muse Muse 175.88008 842.5317 139.551634 712.92878 91.293779
## Laihka Laihka 153.35609 590.5575 65.529010 261.43345 27.758817
## Mongnai Mongnai 182.51928 515.9062 5.141388 267.51285 28.277635
## Mawkmai Mawkmai 97.44231 234.5010 2.780095 36.41924 7.784265
## Kutkai Kutkai 238.71578 474.0161 62.897378 264.62088 21.070884
## Mongton Mongton 193.51808 388.4453 25.129169 290.51198 21.841240
## Mongyai Mongyai 168.44238 364.2707 20.333133 135.12905 9.378752
## Mongkaing Mongkaing 156.74749 116.0299 6.000490 50.75925 8.388440
## Lashio Lashio 235.73893 680.7891 66.685148 463.83909 60.216842
## Mongpan Mongpan 228.74008 517.2477 21.582734 437.74211 46.485888
## Matman Matman 244.12297 219.4093 8.438819 45.20796 6.027728
## Tachileik Tachileik 363.35354 759.4214 59.751756 735.43090 92.401937
## Narphan Narphan 75.27012 210.0886 42.187690 305.26891 3.277892
## Mongkhet Mongkhet 79.37695 313.3956 29.034268 114.64174 6.853583
## Hsipaw Hsipaw 198.12167 475.8613 32.316784 269.08669 14.588719
## Monghsat Monghsat 107.67490 460.1169 34.508769 189.51537 22.817273
## Mongmao Mongmao 120.05744 512.6855 85.495452 424.98803 11.297271
## Nansang Nansang 203.99724 585.6969 37.586810 314.63712 30.641998
## Laukkaing Laukkaing 53.26400 778.5117 134.354578 716.74513 35.556180
## Pangsang Pangsang 97.44765 490.3358 62.569694 440.83757 50.427456
## Namtu Namtu 240.01374 630.6159 35.220342 105.05970 19.929559
## Monghpyak Monghpyak 405.02839 503.3252 42.497972 381.83293 25.141930
## Konkyan Konkyan 21.05456 287.0743 169.351886 316.73380 10.801904
## Mongping Mongping 161.90476 330.8817 24.611033 190.75908 11.598303
## Hopong Hopong 205.55645 455.8395 32.311550 209.96441 14.477515
## Nyaungshwe Nyaungshwe 323.70878 554.4870 18.998921 351.19857 15.691701
## Hsihseng Hsihseng 246.77306 505.5689 31.796405 145.09780 9.917305
## Mongla Mongla 82.18126 673.1951 86.981567 555.10753 62.596006
## Hseni Hseni 257.32235 628.8310 44.825537 431.87028 19.696069
## Kunlong Kunlong 121.92071 589.7806 181.485758 237.58661 20.785219
## Hopang Hopang 127.60443 556.8737 81.746586 487.68817 24.523976
## Namhkan Namhkan 134.98623 653.5462 91.796237 596.48877 30.162955
## Kengtung Kengtung 267.50939 637.7874 63.203895 487.32989 47.542234
## Langkho Langkho 227.46781 587.1483 74.391989 403.91035 32.308059
## Monghsu Monghsu 235.95261 464.9495 11.629171 231.06184 12.389958
## Taunggyi Taunggyi 365.30919 755.2661 81.545688 586.66651 81.170403
## Pangwaun Pangwaun 76.24025 366.7406 28.992770 518.14733 6.013315
## Kyethi Kyethi 268.62150 447.1408 22.357039 89.65285 12.807550
## Loilen Loilen 142.92267 552.6099 21.649390 253.00431 32.015411
## Manton Manton 194.32513 188.3379 8.069764 54.79630 3.644410
## Mongyang Mongyang 71.74622 569.3250 113.944066 469.01868 12.847119
## Kunhing Kunhing 161.48796 473.0853 73.085339 340.48140 26.039387
## Mongyawng Mongyawng 278.08501 739.2953 121.978196 324.06383 15.326276
## Tangyan Tangyan 223.86318 453.2753 22.594047 105.23021 12.065335
## Namhsan Namhsan 230.83668 390.5005 23.090976 97.77128 8.987943
Notice that the row number has been replaced into the township name.
Now, we will delete the TS.x field by using the code chunk below.
shan_ict <- select(cluster_vars, c(2:6))
head(shan_ict)
## RADIO_PR TV_PR LLPHONE_PR MPHONE_PR COMPUTER_PR
## Mongmit 286.1852 554.1313 35.30618 260.6944 12.15939
## Pindaya 417.4647 505.1300 19.83584 162.3917 12.88190
## Ywangan 484.5215 260.5734 11.93591 120.2856 4.41465
## Pinlaung 231.6499 541.7189 28.54454 249.4903 13.76255
## Mabein 449.4903 708.6423 72.75255 392.6089 16.45042
## Kalaw 280.7624 611.6204 42.06478 408.7951 29.63160
In general, multiple variables will be used in cluster analysis. It is not unusual their values range are different. In order to avoid the cluster analysis result is baised to clustering variables with large values, it is useful to standardise the input variables before performing cluster analysis.
In the code chunk below, normalize() of heatmaply package is used to stadardisation the clustering variables by using Min-Max method. The summary() is then used to display the summary statistics of the standardised clustering variables.
shan_ict.std <- normalize(shan_ict)
summary(shan_ict.std)
## RADIO_PR TV_PR LLPHONE_PR MPHONE_PR
## Min. :0.0000 Min. :0.0000 Min. :0.0000 Min. :0.0000
## 1st Qu.:0.2544 1st Qu.:0.4600 1st Qu.:0.1123 1st Qu.:0.2199
## Median :0.4097 Median :0.5523 Median :0.1948 Median :0.3846
## Mean :0.4199 Mean :0.5416 Mean :0.2703 Mean :0.3972
## 3rd Qu.:0.5330 3rd Qu.:0.6750 3rd Qu.:0.3746 3rd Qu.:0.5608
## Max. :1.0000 Max. :1.0000 Max. :1.0000 Max. :1.0000
## COMPUTER_PR
## Min. :0.00000
## 1st Qu.:0.09598
## Median :0.17607
## Mean :0.23692
## 3rd Qu.:0.29868
## Max. :1.00000
Notice that the values range of the Min-max standardised clustering variables are 0-1 now.
Z-score standardisation can be performed easily by using scale() of Base R. The code chunk below will be used to stadardisation the clustering variables by using Z-score method.
shan_ict.z <- scale(shan_ict)
describe(shan_ict.z)
## vars n mean sd median trimmed mad min max range skew kurtosis
## RADIO_PR 1 55 0 1 -0.04 -0.06 0.94 -1.85 2.55 4.40 0.48 -0.27
## TV_PR 2 55 0 1 0.05 0.04 0.78 -2.47 2.09 4.56 -0.38 -0.23
## LLPHONE_PR 3 55 0 1 -0.33 -0.15 0.68 -1.19 3.20 4.39 1.37 1.49
## MPHONE_PR 4 55 0 1 -0.05 -0.06 1.01 -1.58 2.40 3.98 0.48 -0.34
## COMPUTER_PR 5 55 0 1 -0.26 -0.18 0.64 -1.03 3.31 4.34 1.80 2.96
## se
## RADIO_PR 0.13
## TV_PR 0.13
## LLPHONE_PR 0.13
## MPHONE_PR 0.13
## COMPUTER_PR 0.13
Notice the mean and standard deviation of the Z-score standardised clustering variables are 0 and 1 respectively.
Note: describe() of psych package is used here instead of summary() of Base R because the earlier provides standard deviation.
Warning: Z-score standardisation method should only be used if we would assume all variables come from some normal distribution.
Beside reviewing the summary statistics of the standardised clustering variables, it is also a good practice to visualise their distribution graphical.
The code chunk below plot the scaled Radio_PR field.
r <- ggplot(data=ict_derived,
aes(x= `RADIO_PR`)) +
geom_histogram(bins=20,
color="black",
fill="light blue")
shan_ict_s_df <- as.data.frame(shan_ict.std)
s <- ggplot(data=shan_ict_s_df,
aes(x=`RADIO_PR`)) +
geom_histogram(bins=20,
color="black",
fill="light blue") +
ggtitle("Min-Max Standardisation")
shan_ict_z_df <- as.data.frame(shan_ict.z)
z <- ggplot(data=shan_ict_z_df,
aes(x=`RADIO_PR`)) +
geom_histogram(bins=20,
color="black",
fill="light blue") +
ggtitle("Z-score Standardisation")
ggarrange(r, s, z,
ncol = 3,
nrow = 1)
shan_ict_mat <- data.matrix(shan_ict)
Notice that the overall distribution of the clustering variables will change after the data standardisation. Hence, it is advisible NOT to perform data standardisation if the values range of the clustering variables are not very large.
In R, many packages provide functions to calculate distance matrix. We will compute the proximity matrix by using dist() of R.
dist() supports six distance proximity calculations, they are: euclidean, maximum, manhattan, canberra, binary and minkowski. The default is euclidean proximity matrix.
The code chunk below is used to compute the proximity matrix using euclidean method.
proxmat <- dist(shan_ict, method = 'euclidean')
The code chunk below can then be used to list the content of proxmat for visual inspection.
proxmat
## Mongmit Pindaya Ywangan Pinlaung Mabein Kalaw
## Pindaya 171.86828
## Ywangan 381.88259 257.31610
## Pinlaung 57.46286 208.63519 400.05492
## Mabein 263.37099 313.45776 529.14689 312.66966
## Kalaw 160.05997 302.51785 499.53297 181.96406 198.14085
## Pekon 59.61977 117.91580 336.50410 94.61225 282.26877 211.91531
## Lawksawk 140.11550 204.32952 432.16535 192.57320 130.36525 140.01101
## Nawnghkio 89.07103 180.64047 377.87702 139.27495 204.63154 127.74787
## Kyaukme 144.02475 311.01487 505.89191 139.67966 264.88283 79.42225
## Muse 563.01629 704.11252 899.44137 571.58335 453.27410 412.46033
## Laihka 141.87227 298.61288 491.83321 101.10150 345.00222 197.34633
## Mongnai 115.86190 258.49346 422.71934 64.52387 358.86053 200.34668
## Mawkmai 434.92968 437.99577 397.03752 398.11227 693.24602 562.59200
## Kutkai 97.61092 212.81775 360.11861 78.07733 340.55064 204.93018
## Mongton 192.67961 283.35574 361.23257 163.42143 425.16902 267.87522
## Mongyai 256.72744 287.41816 333.12853 220.56339 516.40426 386.74701
## Mongkaing 503.61965 481.71125 364.98429 476.29056 747.17454 625.24500
## Lashio 251.29457 398.98167 602.17475 262.51735 231.28227 106.69059
## Mongpan 193.32063 335.72896 483.68125 192.78316 301.52942 114.69105
## Matman 401.25041 354.39039 255.22031 382.40610 637.53975 537.63884
## Tachileik 529.63213 635.51774 807.44220 555.01039 365.32538 373.64459
## Narphan 406.15714 474.50209 452.95769 371.26895 630.34312 463.53759
## Mongkhet 349.45980 391.74783 408.97731 305.86058 610.30557 465.52013
## Hsipaw 118.18050 245.98884 388.63147 76.55260 366.42787 212.36711
## Monghsat 214.20854 314.71506 432.98028 160.44703 470.48135 317.96188
## Mongmao 242.54541 402.21719 542.85957 217.58854 384.91867 195.18913
## Nansang 104.91839 275.44246 472.77637 85.49572 287.92364 124.30500
## Laukkaing 568.27732 726.85355 908.82520 563.81750 520.67373 427.77791
## Pangsang 272.67383 428.24958 556.82263 244.47146 418.54016 224.03998
## Namtu 179.62251 225.40822 444.66868 170.04533 366.16094 307.27427
## Monghpyak 177.76325 221.30579 367.44835 222.20020 212.69450 167.08436
## Konkyan 403.39082 500.86933 528.12533 365.44693 613.51206 444.75859
## Mongping 265.12574 310.64850 337.94020 229.75261 518.16310 375.64739
## Hopong 136.93111 223.06050 352.85844 98.14855 398.00917 264.16294
## Nyaungshwe 99.38590 216.52463 407.11649 138.12050 210.21337 95.66782
## Hsihseng 131.49728 172.00796 342.91035 111.61846 381.20187 287.11074
## Mongla 384.30076 549.42389 728.16301 372.59678 406.09124 260.26411
## Hseni 189.37188 337.98982 534.44679 204.47572 213.61240 38.52842
## Kunlong 224.12169 355.47066 531.63089 194.76257 396.61508 273.01375
## Hopang 281.05362 443.26362 596.19312 265.96924 368.55167 185.14704
## Namhkan 386.02794 543.81859 714.43173 382.78835 379.56035 246.39577
## Kengtung 246.45691 385.68322 573.23173 263.48638 219.47071 88.29335
## Langkho 164.26299 323.28133 507.78892 168.44228 253.84371 67.19580
## Monghsu 109.15790 198.35391 340.42789 80.86834 367.19820 237.34578
## Taunggyi 399.84278 503.75471 697.98323 429.54386 226.24011 252.26066
## Pangwaun 381.51246 512.13162 580.13146 356.37963 523.44632 338.35194
## Kyethi 202.92551 175.54012 287.29358 189.47065 442.07679 360.17247
## Loilen 145.48666 293.61143 469.51621 91.56527 375.06406 217.19877
## Manton 430.64070 402.42888 306.16379 405.83081 674.01120 560.16577
## Mongyang 309.51302 475.93982 630.71590 286.03834 411.88352 233.56349
## Kunhing 173.50424 318.23811 449.67218 141.58836 375.82140 197.63683
## Mongyawng 214.21738 332.92193 570.56521 235.55497 193.49994 173.43078
## Tangyan 195.92520 208.43740 324.77002 169.50567 448.59948 348.06617
## Namhsan 237.78494 228.41073 286.16305 214.33352 488.33873 385.88676
## Pekon Lawksawk Nawnghkio Kyaukme Muse Laihka
## Pindaya
## Ywangan
## Pinlaung
## Mabein
## Kalaw
## Pekon
## Lawksawk 157.51129
## Nawnghkio 113.15370 90.82891
## Kyaukme 202.12206 186.29066 157.04230
## Muse 614.56144 510.13288 533.68806 434.75768
## Laihka 182.23667 246.74469 211.88187 128.24979 526.65211
## Mongnai 151.60031 241.71260 182.21245 142.45669 571.97975 100.53457
## Mawkmai 416.00669 567.52693 495.15047 512.02846 926.93007 429.96554
## Kutkai 114.98048 224.64646 147.44053 170.93318 592.90743 144.67198
## Mongton 208.14888 311.07742 225.81118 229.28509 634.71074 212.07320
## Mongyai 242.52301 391.26989 319.57938 339.27780 763.91399 264.13364
## Mongkaing 480.23965 625.18712 546.69447 586.05094 995.66496 522.96309
## Lashio 303.80011 220.75270 230.55346 129.95255 313.15288 238.64533
## Mongpan 243.30037 228.54223 172.84425 110.37831 447.49969 210.76951
## Matman 368.25761 515.39711 444.05061 505.52285 929.11283 443.25453
## Tachileik 573.39528 441.82621 470.45533 429.15493 221.19950 549.08985
## Narphan 416.84901 523.69580 435.59661 420.30003 770.40234 392.32592
## Mongkhet 342.08722 487.41102 414.10280 409.03553 816.44931 324.97428
## Hsipaw 145.37542 249.35081 176.09570 163.95741 591.03355 128.42987
## Monghsat 225.64279 352.31496 289.83220 253.25370 663.76026 158.93517
## Mongmao 293.70625 314.64777 257.76465 146.09228 451.82530 185.99082
## Nansang 160.37607 188.78869 151.13185 60.32773 489.35308 78.78999
## Laukkaing 624.82399 548.83928 552.65554 428.74978 149.26996 507.39700
## Pangsang 321.81214 345.91486 287.10769 175.35273 460.24292 214.19291
## Namtu 165.02707 260.95300 257.52713 270.87277 659.16927 185.86794
## Monghpyak 190.93173 142.31691 93.03711 217.64419 539.43485 293.22640
## Konkyan 421.48797 520.31264 439.34272 393.79911 704.86973 351.75354
## Mongping 259.68288 396.47081 316.14719 330.28984 744.44948 272.82761
## Hopong 138.86577 274.91604 204.88286 218.84211 648.68011 157.48857
## Nyaungshwe 139.31874 104.17830 43.26545 126.50414 505.88581 201.71653
## Hsihseng 105.30573 257.11202 209.88026 250.27059 677.66886 175.89761
## Mongla 441.20998 393.18472 381.40808 241.58966 256.80556 315.93218
## Hseni 243.98001 171.50398 164.05304 81.20593 381.30567 204.49010
## Kunlong 249.36301 318.30406 285.04608 215.63037 547.24297 122.68682
## Hopang 336.38582 321.16462 279.84188 154.91633 377.44407 230.78652
## Namhkan 442.77120 379.41126 367.33575 247.81990 238.67060 342.43665
## Kengtung 297.67761 209.38215 208.29647 136.23356 330.08211 258.23950
## Langkho 219.21623 190.30257 156.51662 51.67279 413.64173 160.94435
## Monghsu 113.84636 242.04063 170.09168 200.77712 633.21624 163.28926
## Taunggyi 440.66133 304.96838 344.79200 312.60547 250.81471 425.36916
## Pangwaun 423.81347 453.02765 381.67478 308.31407 541.97887 351.78203
## Kyethi 162.43575 317.74604 267.21607 328.14177 757.16745 255.83275
## Loilen 181.94596 265.29318 219.26405 146.92675 560.43400 59.69478
## Manton 403.82131 551.13000 475.77296 522.86003 941.49778 458.30232
## Mongyang 363.58788 363.37684 323.32123 188.59489 389.59919 229.71502
## Kunhing 213.46379 278.68953 206.15773 145.00266 533.00162 142.03682
## Mongyawng 248.43910 179.07229 220.61209 181.55295 422.37358 211.99976
## Tangyan 167.79937 323.14701 269.07880 306.78359 736.93741 224.29176
## Namhsan 207.16559 362.84062 299.74967 347.85944 778.52971 273.79672
## Mongnai Mawkmai Kutkai Mongton Mongyai Mongkaing
## Pindaya
## Ywangan
## Pinlaung
## Mabein
## Kalaw
## Pekon
## Lawksawk
## Nawnghkio
## Kyaukme
## Muse
## Laihka
## Mongnai
## Mawkmai 374.50873
## Kutkai 91.15307 364.95519
## Mongton 131.67061 313.35220 107.06341
## Mongyai 203.23607 178.70499 188.94166 159.79790
## Mongkaing 456.00842 133.29995 428.96133 365.50032 262.84016
## Lashio 270.86983 638.60773 289.82513 347.11584 466.36472 708.65819
## Mongpan 178.09554 509.99632 185.18173 200.31803 346.39710 563.56780
## Matman 376.33870 147.83545 340.86349 303.04574 186.95158 135.51424
## Tachileik 563.95232 919.38755 568.99109 608.76740 750.29555 967.14087
## Narphan 329.31700 273.75350 314.27683 215.97925 248.82845 285.65085
## Mongkhet 275.76855 115.58388 273.91673 223.22828 104.98924 222.60577
## Hsipaw 52.68195 351.34601 51.46282 90.69766 177.33790 423.77868
## Monghsat 125.25968 275.09705 154.32012 150.98053 127.35225 375.60376
## Mongmao 188.29603 485.52853 204.69232 206.57001 335.61300 552.31959
## Nansang 92.79567 462.41938 130.04549 199.58124 288.55962 542.16609
## Laukkaing 551.56800 882.51110 580.38112 604.66190 732.68347 954.11795
## Pangsang 204.25746 484.14757 228.33583 210.77938 343.30638 548.40662
## Namtu 209.35473 427.95451 225.28268 308.71751 278.02761 525.04057
## Monghpyak 253.26470 536.71695 206.61627 258.04282 370.01575 568.21089
## Konkyan 328.82831 339.01411 310.60810 248.25265 287.87384 380.92091
## Mongping 202.99615 194.31049 182.75266 119.86993 65.38727 257.18572
## Hopong 91.53795 302.84362 73.45899 106.21031 124.62791 379.37916
## Nyaungshwe 169.63695 502.99026 152.15482 219.72196 327.13541 557.32112
## Hsihseng 142.36728 329.29477 128.21054 194.64317 162.27126 411.59788
## Mongla 354.10985 686.88950 388.40984 411.06668 535.28615 761.48327
## Hseni 216.81639 582.53670 229.37894 286.75945 408.23212 648.04408
## Kunlong 202.92529 446.53763 204.54010 270.02165 299.36066 539.91284
## Hopang 243.00945 561.24281 263.31986 273.50305 408.73288 626.17673
## Namhkan 370.05669 706.47792 392.48568 414.53594 550.62819 771.39688
## Kengtung 272.28711 632.54638 279.19573 329.38387 460.39706 692.74693
## Langkho 174.67678 531.08019 180.51419 236.70878 358.95672 597.42714
## Monghsu 84.11238 332.07962 62.60859 107.04894 154.86049 400.71816
## Taunggyi 448.55282 810.74692 450.33382 508.40925 635.94105 866.21117
## Pangwaun 312.13429 500.68857 321.80465 257.50434 394.07696 536.95736
## Kyethi 210.50453 278.85535 184.23422 222.52947 137.79420 352.06533
## Loilen 58.41263 388.73386 131.56529 176.16001 224.79239 482.18190
## Manton 391.54062 109.08779 361.82684 310.20581 195.59882 81.75337
## Mongyang 260.39387 558.83162 285.33223 295.60023 414.31237 631.91325
## Kunhing 110.55197 398.43973 108.84990 114.03609 238.99570 465.03971
## Mongyawng 275.77546 620.04321 281.03383 375.22688 445.78964 700.98284
## Tangyan 180.37471 262.66006 166.61820 198.88460 109.08506 348.56123
## Namhsan 218.10003 215.19289 191.32762 196.76188 77.35900 288.66231
## Lashio Mongpan Matman Tachileik Narphan Mongkhet
## Pindaya
## Ywangan
## Pinlaung
## Mabein
## Kalaw
## Pekon
## Lawksawk
## Nawnghkio
## Kyaukme
## Muse
## Laihka
## Mongnai
## Mawkmai
## Kutkai
## Mongton
## Mongyai
## Mongkaing
## Lashio
## Mongpan 172.33279
## Matman 628.11049 494.81014
## Tachileik 311.95286 411.03849 890.12935
## Narphan 525.63854 371.13393 312.05193 760.29566
## Mongkhet 534.44463 412.17123 203.02855 820.50164 217.28718
## Hsipaw 290.86435 179.52054 344.45451 576.18780 295.40170 253.80950
## Monghsat 377.86793 283.30992 313.59911 677.09508 278.21548 167.98445
## Mongmao 214.23677 131.59966 501.59903 472.95568 331.42618 375.35820
## Nansang 184.47950 144.77393 458.06573 486.77266 398.13308 360.99219
## Laukkaing 334.65738 435.58047 903.72094 325.06329 708.82887 769.06406
## Pangsang 236.72516 140.23910 506.29940 481.31907 316.30314 375.58139
## Namtu 365.88437 352.91394 416.65397 659.56458 494.36143 355.99713
## Monghpyak 262.09281 187.85699 470.46845 444.04411 448.40651 462.63265
## Konkyan 485.51312 365.87588 392.40306 730.92980 158.82353 254.24424
## Mongping 454.52548 318.47482 201.65224 727.08969 188.64567 113.80917
## Hopong 345.31042 239.43845 291.84351 632.45718 294.40441 212.99485
## Nyaungshwe 201.58191 137.29734 460.91883 445.81335 427.94086 417.08639
## Hsihseng 369.00833 295.87811 304.02806 658.87060 377.52977 256.70338
## Mongla 179.95877 253.20001 708.17595 347.33155 531.46949 574.40292
## Hseni 79.41836 120.66550 564.64051 354.90063 474.12297 481.88406
## Kunlong 295.23103 288.03320 468.27436 595.70536 413.07823 341.68641
## Hopang 170.63913 135.62913 573.55355 403.82035 397.85908 451.51070
## Namhkan 173.27153 240.34131 715.42102 295.91660 536.85519 596.19944
## Kengtung 59.85893 142.21554 613.01033 295.90429 505.40025 531.35998
## Langkho 115.18145 94.98486 518.86151 402.33622 420.65204 428.08061
## Monghsu 325.71557 216.25326 308.13805 605.02113 311.92379 247.73318
## Taunggyi 195.14541 319.81385 778.45810 150.84117 684.20905 712.80752
## Pangwaun 362.45608 232.52209 523.43600 540.60474 264.64997 407.02947
## Kyethi 447.10266 358.89620 233.83079 728.87329 374.90376 233.25039
## Loilen 268.92310 207.25000 406.56282 573.75476 354.79137 284.76895
## Manton 646.66493 507.96808 59.52318 910.23039 280.26395 181.33894
## Mongyang 209.33700 194.93467 585.61776 448.79027 401.39475 445.40621
## Kunhing 255.10832 137.85278 403.66587 532.26397 281.62645 292.49814
## Mongyawng 172.70139 275.15989 601.80824 432.10118 572.76394 522.91815
## Tangyan 429.84475 340.39128 242.78233 719.84066 348.84991 201.49393
## Namhsan 472.04024 364.77086 180.09747 754.03913 316.54695 170.90848
## Hsipaw Monghsat Mongmao Nansang Laukkaing Pangsang
## Pindaya
## Ywangan
## Pinlaung
## Mabein
## Kalaw
## Pekon
## Lawksawk
## Nawnghkio
## Kyaukme
## Muse
## Laihka
## Mongnai
## Mawkmai
## Kutkai
## Mongton
## Mongyai
## Mongkaing
## Lashio
## Mongpan
## Matman
## Tachileik
## Narphan
## Mongkhet
## Hsipaw
## Monghsat 121.78922
## Mongmao 185.99483 247.17708
## Nansang 120.24428 201.92690 164.99494
## Laukkaing 569.06099 626.44910 404.00848 480.60074
## Pangsang 205.04337 256.37933 57.60801 193.36162 408.04016
## Namtu 229.44658 231.78673 365.03882 217.61884 664.06286 392.97391
## Monghpyak 237.67919 356.84917 291.88846 227.52638 565.84279 315.11651
## Konkyan 296.74316 268.25060 281.87425 374.70456 635.92043 274.81900
## Mongping 168.92101 140.95392 305.57166 287.36626 708.13447 308.33123
## Hopong 62.86179 100.45714 244.16253 167.66291 628.48557 261.51075
## Nyaungshwe 169.92664 286.37238 230.45003 131.18943 520.24345 257.77823
## Hsihseng 136.54610 153.49551 311.98001 193.53779 670.74564 335.52974
## Mongla 373.47509 429.00536 216.24705 289.45119 202.55831 217.88123
## Hseni 231.48538 331.22632 184.67099 136.45492 391.74585 214.66375
## Kunlong 205.10051 202.31862 224.43391 183.01388 521.88657 258.49342
## Hopang 248.72536 317.64824 78.29342 196.47091 331.67199 92.57672
## Namhkan 382.79302 455.10875 223.32205 302.89487 196.46063 231.38484
## Kengtung 284.08582 383.72138 207.58055 193.67980 351.48520 229.85484
## Langkho 183.05109 279.52329 134.50170 99.39859 410.41270 167.65920
## Monghsu 58.55724 137.24737 242.43599 153.59962 619.01766 260.52971
## Taunggyi 462.31183 562.88102 387.33906 365.04897 345.98041 405.59730
## Pangwaun 298.12447 343.53898 187.40057 326.12960 470.63605 157.48757
## Kyethi 195.17677 190.50609 377.89657 273.02385 749.99415 396.89963
## Loilen 98.04789 118.65144 190.26490 94.23028 535.57527 207.94433
## Manton 359.60008 317.15603 503.79786 476.55544 907.38406 504.75214
## Mongyang 267.10497 312.64797 91.06281 218.49285 326.19219 108.37735
## Kunhing 90.77517 165.38834 103.91040 128.20940 500.41640 123.18870
## Mongyawng 294.70967 364.40429 296.40789 191.11990 454.80044 336.16703
## Tangyan 167.69794 144.59626 347.14183 249.70235 722.40954 364.76893
## Namhsan 194.47928 169.56962 371.71448 294.16284 760.45960 385.65526
## Namtu Monghpyak Konkyan Mongping Hopong Nyaungshwe
## Pindaya
## Ywangan
## Pinlaung
## Mabein
## Kalaw
## Pekon
## Lawksawk
## Nawnghkio
## Kyaukme
## Muse
## Laihka
## Mongnai
## Mawkmai
## Kutkai
## Mongton
## Mongyai
## Mongkaing
## Lashio
## Mongpan
## Matman
## Tachileik
## Narphan
## Mongkhet
## Hsipaw
## Monghsat
## Mongmao
## Nansang
## Laukkaing
## Pangsang
## Namtu
## Monghpyak 346.57799
## Konkyan 478.37690 463.39594
## Mongping 321.66441 354.76537 242.02901
## Hopong 206.82668 267.95563 304.49287 134.00139
## Nyaungshwe 271.41464 103.97300 432.35040 319.32583 209.32532
## Hsihseng 131.89940 285.37627 383.49700 199.64389 91.65458 225.80242
## Mongla 483.49434 408.03397 468.09747 512.61580 432.31105 347.60273
## Hseni 327.41448 200.26876 448.84563 395.58453 286.41193 130.86310
## Kunlong 233.60474 357.44661 329.11433 309.05385 219.06817 285.13095
## Hopang 408.24516 304.26577 348.18522 379.27212 309.77356 247.19891
## Namhkan 506.32466 379.50202 481.59596 523.74815 444.13246 333.32428
## Kengtung 385.33554 221.47613 474.82621 442.80821 340.47382 177.75714
## Langkho 305.03473 200.27496 386.95022 343.96455 239.63685 128.26577
## Monghsu 209.64684 232.17823 331.72187 158.90478 43.40665 173.82799
## Taunggyi 518.72748 334.17439 650.56905 621.53039 513.76415 325.09619
## Pangwaun 517.03554 381.95144 263.97576 340.37881 346.00673 352.92324
## Kyethi 186.90932 328.16234 400.10989 187.43974 136.49038 288.06872
## Loilen 194.24075 296.99681 334.19820 231.99959 124.74445 206.40432
## Manton 448.58230 502.20840 366.66876 200.48082 310.58885 488.79874
## Mongyang 413.26052 358.17599 329.39338 387.80686 323.35704 294.29500
## Kunhing 296.43996 250.74435 253.74202 212.59619 145.15617 189.97131
## Mongyawng 262.24331 285.56475 522.38580 455.59190 326.59925 218.12104
## Tangyan 178.69483 335.26416 367.46064 161.67411 106.82328 284.14692
## Namhsan 240.95555 352.70492 352.20115 130.23777 132.70541 315.91750
## Hsihseng Mongla Hseni Kunlong Hopang Namhkan
## Pindaya
## Ywangan
## Pinlaung
## Mabein
## Kalaw
## Pekon
## Lawksawk
## Nawnghkio
## Kyaukme
## Muse
## Laihka
## Mongnai
## Mawkmai
## Kutkai
## Mongton
## Mongyai
## Mongkaing
## Lashio
## Mongpan
## Matman
## Tachileik
## Narphan
## Mongkhet
## Hsipaw
## Monghsat
## Mongmao
## Nansang
## Laukkaing
## Pangsang
## Namtu
## Monghpyak
## Konkyan
## Mongping
## Hopong
## Nyaungshwe
## Hsihseng
## Mongla 478.66210
## Hseni 312.74375 226.82048
## Kunlong 231.85967 346.46200 276.19175
## Hopang 370.01334 147.02444 162.80878 271.34451
## Namhkan 492.09476 77.21355 212.11323 375.73885 146.18632
## Kengtung 370.72441 202.45004 66.12817 317.14187 164.29921 175.63015
## Langkho 276.27441 229.01675 66.66133 224.52741 134.24847 224.40029
## Monghsu 97.82470 424.51868 262.28462 239.89665 301.84458 431.32637
## Taunggyi 528.14240 297.09863 238.19389 471.29032 329.95252 257.29147
## Pangwaun 433.06326 319.18643 330.70182 392.45403 206.98364 310.44067
## Kyethi 84.04049 556.02500 388.33498 298.55859 440.48114 567.86202
## Loilen 158.84853 338.67408 227.10984 166.53599 242.89326 364.90647
## Manton 334.87758 712.51416 584.63341 479.76855 577.52046 721.86149
## Mongyang 382.59743 146.66661 210.19929 247.22785 69.25859 167.72448
## Kunhing 220.15490 306.47566 206.47448 193.77551 172.96164 314.92119
## Mongyawng 309.51462 315.57550 173.86004 240.39800 290.51360 321.21112
## Tangyan 70.27241 526.80849 373.07575 268.07983 412.22167 542.64078
## Namhsan 125.74240 564.02740 411.96125 310.40560 440.51555 576.42717
## Kengtung Langkho Monghsu Taunggyi Pangwaun Kyethi
## Pindaya
## Ywangan
## Pinlaung
## Mabein
## Kalaw
## Pekon
## Lawksawk
## Nawnghkio
## Kyaukme
## Muse
## Laihka
## Mongnai
## Mawkmai
## Kutkai
## Mongton
## Mongyai
## Mongkaing
## Lashio
## Mongpan
## Matman
## Tachileik
## Narphan
## Mongkhet
## Hsipaw
## Monghsat
## Mongmao
## Nansang
## Laukkaing
## Pangsang
## Namtu
## Monghpyak
## Konkyan
## Mongping
## Hopong
## Nyaungshwe
## Hsihseng
## Mongla
## Hseni
## Kunlong
## Hopang
## Namhkan
## Kengtung
## Langkho 107.16213
## Monghsu 316.91914 221.84918
## Taunggyi 186.28225 288.27478 486.91951
## Pangwaun 337.48335 295.38434 343.38498 497.61245
## Kyethi 444.26274 350.91512 146.61572 599.57407 476.62610
## Loilen 282.22935 184.10672 131.55208 455.91617 331.69981 232.32965
## Manton 631.99123 535.95620 330.76503 803.08034 510.79265 272.03299
## Mongyang 217.08047 175.35413 323.95988 374.58247 225.25026 453.86726
## Kunhing 245.95083 146.38284 146.78891 429.98509 229.09986 278.95182
## Mongyawng 203.87199 186.11584 312.85089 287.73864 475.33116 387.71518
## Tangyan 429.95076 332.02048 127.42203 592.65262 447.05580 47.79331
## Namhsan 466.20497 368.20978 153.22576 631.49232 448.58030 68.67929
## Loilen Manton Mongyang Kunhing Mongyawng Tangyan
## Pindaya
## Ywangan
## Pinlaung
## Mabein
## Kalaw
## Pekon
## Lawksawk
## Nawnghkio
## Kyaukme
## Muse
## Laihka
## Mongnai
## Mawkmai
## Kutkai
## Mongton
## Mongyai
## Mongkaing
## Lashio
## Mongpan
## Matman
## Tachileik
## Narphan
## Mongkhet
## Hsipaw
## Monghsat
## Mongmao
## Nansang
## Laukkaing
## Pangsang
## Namtu
## Monghpyak
## Konkyan
## Mongping
## Hopong
## Nyaungshwe
## Hsihseng
## Mongla
## Hseni
## Kunlong
## Hopang
## Namhkan
## Kengtung
## Langkho
## Monghsu
## Taunggyi
## Pangwaun
## Kyethi
## Loilen
## Manton 419.06087
## Mongyang 246.76592 585.70558
## Kunhing 130.39336 410.49230 188.89405
## Mongyawng 261.75211 629.43339 304.21734 295.35984
## Tangyan 196.60826 271.82672 421.06366 249.74161 377.52279
## Namhsan 242.15271 210.48485 450.97869 270.79121 430.02019 63.67613
In R, there are several packages provide hierarchical clustering function. In this hands-on exercise, hclust() of R stats will be used.
hclust() employed agglomeration method to compute the cluster. Eight clustering algorithms are supported, they are: ward.D, ward.D2, single, complete, average(UPGMA), mcquitty(WPGMA), median(WPGMC) and centroid(UPGMC).
The code chunk below performs hierarchical cluster analysis using ward.D method. The hierarchical clustering output is stored in an object of class hclust which describes the tree produced by the clustering process.
hclust_ward <- hclust(proxmat, method = 'ward.D')
We can then plot the tree by using plot() of R Graphicas as shown in the code chunk below
plot(hclust_ward, cex = 0.6)
One of the challenge in performing hierarchical clustering is to identify stronger clustering structures. The issue can be solved by using use agnes() function of cluster package. It functions like hclus(), however, with the agnes() function you can also get the agglomerative coefficient, which measures the amount of clustering structure found (values closer to 1 suggest strong clustering structure).
The code chunk below will be used to compute the agglomerative coefficients of all hierarchical clustering algorithms.
m <- c( "average", "single", "complete", "ward")
names(m) <- c( "average", "single", "complete", "ward")
ac <- function(x) {
agnes(shan_ict, method = x)$ac
}
map_dbl(m, ac)
## average single complete ward
## 0.8131144 0.6628705 0.8950702 0.9427730
With reference to the output above, we can see that Ward’s method provides the strongest clustering structure among the four methods assessed. Hence, in the subsequent analysis, only Ward’s method will be used.
In the dendrogram displayed above, each leaf corresponds to one observation. As we move up the tree, observations that are similar to each other are combined into branches, which are themselves fused at a higher height.
The height of the fusion, provided on the vertical axis, indicates the (dis)similarity between two observations. The higher the height of the fusion, the less similar the observations are. Note that, conclusions about the proximity of two observations can be drawn only based on the height where branches containing those two observations first are fused. We cannot use the proximity of two observations along the horizontal axis as a criteria of their similarity.
It’s also possible to draw the dendrogram with a border around the selected clusters by using rect.hclust() of R stats. The argument border is used to specify the border colors for the rectangles.
plot(hclust_ward, cex = 0.6)
rect.hclust(hclust_ward, k = 5, border = 2:5)
### Visually-driven hierarchical clustering analysis In this section, we will learn how to perform visually-driven hiearchical clustering analysis by using heatmaply package.
With heatmaply, we are able to build both highly interactive cluster heatmap or static cluster heatmap.
The data was loaded into a data frame, but it has to be a data matrix to make your heatmap.
The code chunk below will be used to transform shan_ict data frame into a data matrix.
shan_ict_mat <- data.matrix(shan_ict)
In the code chunk below, the heatmaply() is used to build an interactive cluster heatmap.
heatmaply(shan_ict_mat,
Colv=NA,
dist_method = "euclidean",
hclust_method = "ward.D",
seriate = "OLO",
colors = Blues,
k_row = 5,
margins = c(NA,200,60,NA),
fontsize_row = 4,
fontsize_col = 5,
main="Geographic Segmentation of Shan State by ICT indicators",
xlab = "ICT Indicators",
ylab = "Townships of Shan State"
)
## Warning in doTryCatch(return(expr), name, parentenv, handler): unable to load shared object '/Library/Frameworks/R.framework/Resources/modules//R_X11.so':
## dlopen(/Library/Frameworks/R.framework/Resources/modules//R_X11.so, 6): Library not loaded: /opt/X11/lib/libSM.6.dylib
## Referenced from: /Library/Frameworks/R.framework/Resources/modules//R_X11.so
## Reason: image not found
With closed examination of the dendragram above, we have decided to retain five clusters.
cutree() of R Base will be used in the code chunk below to derive a 5-cluster model.
groups <- as.factor(cutree(hclust_ward, k=5))
The output is called groups. It is a list object.
In order to visualise the clusters, the groups object need to be appended onto shan_sf simple feature object.
The code chunk below form the join in three steps: 1. the groups list object will be converted into a matrix; 2. cbind() is used to append groups matrix onto shan_sf to produce an output simple feature object called shan_sf_cluster; and 3. rename of dplyr package is used to rename as.matrix.groups field as CLUSTER.
shan_sf_cluster <- cbind(shan_sf, as.matrix(groups)) %>%
rename(`CLUSTER`=`as.matrix.groups.`)
Next, qtm() of tmap package is used to plot the choropleth map showing the cluster formed.
qtm(shan_sf_cluster, "CLUSTER")
The choropleth map above reveals the clusters are very fragmented. The is one of the major limitation when non-spatial clustering algorithm such as hierarchical cluster analysis method is used.
In this section, you will learn how to derive spatially constrained cluster by using SKATER method.
First, we need to convert shan_sf into SpatialPolygonDataFrame. This is because SKATER function only support sp objects such as SpatialPolygonDataFrame.
The code chunk below uses as_Spatial() of sf package to convert shan_sf into a SpatialPolygonDataFrame called shan_sp.
shan_sp <- as_Spatial(shan_sf)
Next, poly2nd() of spdep package will be used to compute the neighbours list from polygon list.
shan.nb <- poly2nb(shan_sp)
summary(shan.nb)
## Neighbour list object:
## Number of regions: 55
## Number of nonzero links: 264
## Percentage nonzero weights: 8.727273
## Average number of links: 4.8
## Link number distribution:
##
## 2 3 4 5 6 7 8 9
## 5 9 7 21 4 3 5 1
## 5 least connected regions:
## 3 5 7 9 47 with 2 links
## 1 most connected region:
## 8 with 9 links
We can plot the neighbours list on shan_sp by using the code chunk below. Since we now can plot the community area boundaries as well, we plot this graph on top of the map. The first plot command gives the boundaries. This is followed by the plot of the neighbor list object, with coordinates applied to the original SpatialPolygonDataFrame (Shan state township boundaries) to extract the centroids of the polygons. These are used as the nodes for the graph representation. We also set the color to blue and specify add=TRUE to plot the network on top of the boundaries.
plot(shan_sp, border=grey(.5))
plot(shan.nb, coordinates(shan_sp), col="blue", add=TRUE)
Note that if you plot the network first and then the boundaries, some of the areas will be clipped. This is because the plotting area is determined by the characteristics of the first plot. In this example, because the boundary map extends further than the graph, we plot it first.
Next, nbcosts() of spdep package is used to compute the cost of each edge. It is the distance between it nodes. This function compute this distance using a data.frame with observations vector in each node.
The code chunk below is used to compute the cost of each edge.
lcosts <- nbcosts(shan.nb, shan_ict)
For each observation, this gives the pairwise dissimilarity between its values on the five variables and the values for the neighbouring observation (from the neighbour list). Basically, this is the notion of a generalised weight for a spatial weights matrix.
Next, We will incorporate these costs into a weights object in the same way as we did in the calculation of inverse of distance weights. In other words, we convert the neighbour list to a list weights object by specifying the just computed lcosts as the weights.
In order to achieve this, nb2listw() of spdep package is used as shown in the code chunk below.
Note that we specify the style as B to make sure the cost values are not row-standardised
shan.w <- nb2listw(shan.nb, lcosts, style="B")
summary(shan.w)
## Characteristics of weights list object:
## Neighbour list object:
## Number of regions: 55
## Number of nonzero links: 264
## Percentage nonzero weights: 8.727273
## Average number of links: 4.8
## Link number distribution:
##
## 2 3 4 5 6 7 8 9
## 5 9 7 21 4 3 5 1
## 5 least connected regions:
## 3 5 7 9 47 with 2 links
## 1 most connected region:
## 8 with 9 links
##
## Weights style: B
## Weights constants summary:
## n nn S0 S1 S2
## B 55 3025 76267.65 58260785 522016004
The minimum spanning tree is computed by mean of the mstree() of spdep package as shown in the code chunk below.
shan.mst <- mstree(shan.w)
After computing the MST, we can check its class and dimension by using the code chunk below.
class(shan.mst)
## [1] "mst" "matrix"
dim(shan.mst)
## [1] 54 3
Note that the dimension is 54 and not 55. This is because the minimum spanning tree consists on n-1 edges (links) in order to traverse all the nodes.
We can display the content of shan.mst by using head() as shown in the code chunk below.
head(shan.mst)
## [,1] [,2] [,3]
## [1,] 23 47 264.64997
## [2,] 47 27 187.40057
## [3,] 27 30 57.60801
## [4,] 27 41 78.29342
## [5,] 30 51 108.37735
## [6,] 51 38 146.66661
The plot method for the MST include a way to show the observation numbers of the nodes in addition to the edge. As before, we plot this together with the township boundaries. We can see how the initial neighbour list is simplified to just one edge connecting each of the nodes, while passing through all the nodes.
plot(shan_sp, border=gray(.5))
plot.mst(shan.mst, coordinates(shan_sp),
col="blue", cex.lab=0.7, cex.circles=0.005, add=TRUE)
The code chunk below compute the spatially constrained cluster using skater() of spdep package.
clust5 <- skater(shan.mst[,1:2], shan_ict, 4)
The skater() takes three mandatory arguments: - the first two columns of the MST matrix (i.e. not the cost), - the data matrix (to update the costs as units are being grouped), and - the number of cuts. Note: It is set to one less than the number of clusters. So, the value specified is not the number of clusters, but the number of cuts in the graph, one less than the number of custers.
The result of the skater() is an object of class skater. We can examine its contents by using the code chunk below.
str(clust5)
## List of 8
## $ groups : num [1:55] 3 3 3 3 3 3 3 3 3 3 ...
## $ edges.groups:List of 5
## ..$ :List of 3
## .. ..$ node: num 23
## .. ..$ edge: num[0 , 1:3]
## .. ..$ ssw : num 0
## ..$ :List of 3
## .. ..$ node: num [1:22] 13 48 54 55 45 37 34 16 25 52 ...
## .. ..$ edge: num [1:21, 1:3] 48 55 54 37 34 16 45 25 13 13 ...
## .. ..$ ssw : num 3423
## ..$ :List of 3
## .. ..$ node: num [1:12] 10 9 6 2 8 1 4 36 46 3 ...
## .. ..$ edge: num [1:11, 1:3] 2 6 8 1 36 4 6 10 10 8 ...
## .. ..$ ssw : num 1846
## ..$ :List of 3
## .. ..$ node: num [1:2] 44 20
## .. ..$ edge: num [1, 1:3] 44 20 95
## .. ..$ ssw : num 95
## ..$ :List of 3
## .. ..$ node: num [1:18] 47 53 38 42 15 41 51 43 32 30 ...
## .. ..$ edge: num [1:17, 1:3] 53 15 42 38 41 51 15 47 15 43 ...
## .. ..$ ssw : num 3759
## $ not.prune : NULL
## $ candidates : int [1:5] 1 2 3 4 5
## $ ssto : num 12613
## $ ssw : num [1:5] 12613 10977 9962 9540 9123
## $ crit : num [1:2] 1 Inf
## $ vec.crit : num [1:55] 1 1 1 1 1 1 1 1 1 1 ...
## - attr(*, "class")= chr "skater"
The most interesting component of this list structure is the groups vector containing the labels of the cluster to which each observation belongs (as before, the label itself is arbitary). This is followed by a detailed summary for each of the clusters in the edges.groups list. Sum of squares measures are given as ssto for the total and ssw to show the effect of each of the cuts on the overall criterion.
We can check the cluster assignment by using the conde chunk below.
ccs5 <- clust5$groups
ccs5
## [1] 3 3 3 3 3 3 3 3 3 3 5 2 2 2 5 2 2 2 5 4 2 5 1 2 2 2 5 2 5 5 2 5 5 2 2 3 2 5
## [39] 5 5 5 5 5 4 2 3 5 2 2 2 5 2 5 2 2
We can find out how many observations are in each cluster by means of the table command. Parenthetially, we can also find this as the dimension of each vector in the lists contained in edges.groups. For example, the first list has node with dimension 12, which is also the number of observations in the first cluster.
table(ccs5)
## ccs5
## 1 2 3 4 5
## 1 22 12 2 18
Lastly, we can also plot the pruned tree that shows the five clusters on top of the townshop area.
plot(shan_sp, border=gray(.5))
plot(clust5, coordinates(shan_sp), cex.lab=.7,
groups.colors=c("red","green","blue", "brown", "pink"), cex.circles=0.005, add=TRUE)
## Warning in segments(coords[id1, 1], coords[id1, 2], coords[id2, 1],
## coords[id2, : "add" is not a graphical parameter
## Warning in segments(coords[id1, 1], coords[id1, 2], coords[id2, 1],
## coords[id2, : "add" is not a graphical parameter
## Warning in segments(coords[id1, 1], coords[id1, 2], coords[id2, 1],
## coords[id2, : "add" is not a graphical parameter
## Warning in segments(coords[id1, 1], coords[id1, 2], coords[id2, 1],
## coords[id2, : "add" is not a graphical parameter
The code chunk below is used to plot the newly derived clusters by using SKATER method.
groups_mat <- as.matrix(clust5$groups)
shan_sf_spatialcluster <- cbind(shan_sf_cluster, as.factor(groups_mat)) %>%
rename(`SP_CLUSTER`=`as.factor.groups_mat.`)
qtm(shan_sf_spatialcluster, "SP_CLUSTER")