Toasmina, Madagascar Population Map Metadata Report

Prediction Weighting Layer Used in Population Redistribution

The data presented below represent the predicted number of people per ~100 m pixel as estimated using the random forest (RF) model as described in Stevens, et al. (2015). The following pages contain a description of the RF model and its covariates, their sources and any metadata collected for each covariate. The prediction weighting layer is used to dasymetrically redistribute the census counts and project counts to match estimated populations based on UN estimates for the final population maps provided by WorldPop.

Stevens, F. R., Gaughan, A. E., Linard, C., & Tatem, A. J. (2015). Disaggregating Census Data for Population Mapping Using Random Forests with Remotely-Sensed and Ancillary Data. PLOS ONE, 10(2), e0107042. doi:10.1371/journal.pone.0107042

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Toasmina, Madagascar Census Data and Observed Population Density

These data are the population density values used to estimate the RF model used to create the prediction weighting layer you see above. Values represent population density as measured by people per hectare and calculated from population counts within each census unit. These values are used as the dependent variable during model estimation.

Madagascar Census Data, 2006, Admin-level 2

Folder: Census
File Name: MDG_TOA.shp
Source: Estimates derived from RGPH (Recensement Général de la Population et de l'Habitat) 1993, Institut National de la Statistique, Madagascar
Description: These census data were extracted from GeoHive (www.geohive.com). Required fields for map production are ADMINID and ADMINPOP.
Class: polygon
Derived Covariates:
area, buff, zones,

class       : SpatialPolygonsDataFrame 
nfeatures   : 138 
extent      : 962109, 969007, 7982719, 7994233  (xmin, xmax, ymin, ymax)
coord. ref. : NA 
nvariables  : 27

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Random Forest Model and Diagnostics

These output and figures outline the estimated RF model that is used to predict the population density weighting layer. The model is fitted to the population density values for the preceding census data using covariates aggregatedfrom the ancillary data sources summarized following the model diagnostics.


Call:
 randomForest(x = x_data, y = y_data, ntree = popfit$ntree, mtry = popfit$mtry,      nodesize = length(y_data)/1000, importance = TRUE, proximity = TRUE) 
               Type of random forest: regression
                     Number of trees: 500
No. of variables tried at each split: 7

          Mean of squared residuals: 0.27
                    % Var explained: 72

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Covariate Metadata

Folder: Landcover
File Name: mdg_lc.tif
Source:
Description:
Class: raster
Derived Covariates:
cls011, dst011, cls040, dst040, cls130, dst130, cls140, dst140, cls150, dst150, cls160, dst160, cls200, dst200, cls210, dst210, cls230, dst230, cls240, dst240, cls250, dst250,

class       : RasterBrick 
dimensions  : 316, 270, 85320, 1  (nrow, ncol, ncell, nlayers)
resolution  : 100, 100  (x, y)
extent      : 952029, 979029, 7972714, 8004314  (xmin, xmax, ymin, ymax)
coord. ref. : +proj=utm +zone=38 +south +datum=WGS84 +units=m +no_defs +ellps=WGS84 +towgs84=0,0,0 
data source : D:\APRF\RF\data\TOA\Landcover\Derived\landcover.tif 
names       : landcover 
min values  :        11 
max values  :       240 

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Suomi NPP VIIRS-Derived 2012 Lights at Night, 15 arc-second

Folder: Lights
File Name: DEFAULT: VIIRS 2012
Source: http://ngdc.noaa.gov/eog/viirs/download_viirs_ntl.html
Description: These 'Lights at Night' data were derived from imagery collected by the Suomi National Polar-orbiting Partnership (NPP) Visible Infrared Imaging Radiometer Suite (VIIRS) sensor. Data were collected in 2012 on moonless nights and though background noise associated with fires, gas-flares, volcanoes or aurora have not been removed it represents the best-available data for night-time light production.
Class: raster
Derived Covariates:
,

class       : RasterBrick 
dimensions  : 316, 270, 85320, 1  (nrow, ncol, ncell, nlayers)
resolution  : 100, 100  (x, y)
extent      : 952029, 979029, 7972714, 8004314  (xmin, xmax, ymin, ymax)
coord. ref. : +proj=utm +zone=38 +south +datum=WGS84 +units=m +no_defs +ellps=WGS84 +towgs84=0,0,0 
data source : D:\APRF\RF\data\TOA\Lights\Derived\lights.tif 
names       : lights 
min values  :  0.027 
max values  :     61 

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Elevation and Derived Slope, 3 second

Folder: Elevation
File Name: DEFAULT: Void-Filled DEM.gdb
Source: HydroSHEDS Void-Filled DEM (Lehnert, et al., 2006), http://hydrosheds.cr.usgs.gov/dataavail.php
Description: The HydroSHEDS data are the result of an effort to provide a globally consistent dataset consisting of NASA's Shuttle Radar Topography Mission (SRTM) data and have been processed, void-filled and corrected for use at large scales.
Class: raster
Derived Covariates:
, slope,

class       : RasterBrick 
dimensions  : 316, 270, 85320, 1  (nrow, ncol, ncell, nlayers)
resolution  : 100, 100  (x, y)
extent      : 952029, 979029, 7972714, 8004314  (xmin, xmax, ymin, ymax)
coord. ref. : +proj=utm +zone=38 +south +datum=WGS84 +units=m +no_defs +ellps=WGS84 +towgs84=0,0,0 
data source : D:\APRF\RF\data\TOA\Elevation\Derived\elevation.tif 
names       : elevation 
min values  :         0 
max values  :       200 

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Primary roads (OSM), 2017

Folder: PrimaryRoads
File Name: Primary_roads.shp
Source: Open Street Map, Downloaded 2017-08-21, http://extract.bbbike.org/
Description: These data were downloaded as part of a per-country package of data layers made availalble as shapefiles through the http://extract.bbbike.org website, extracted from the Open Street Map (OSM) database.
Class: linear
Derived Covariates:
cls, dst,

class       : SpatialLinesDataFrame 
nfeatures   : 33 
extent      : 953814, 968337, 7979043, 7988968  (xmin, xmax, ymin, ymax)
coord. ref. : NA 
nvariables  : 7

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Secondary roads (OSM), 2017

Folder: SecondaryRoads
File Name: SecondaryRoads.shp
Source: Open Street Map, Downloaded 2017-08-21, http://extract.bbbike.org/
Description: These data were downloaded as part of a per-country package of data layers made availalble as shapefiles through the http://extract.bbbike.org website, extracted from the Open Street Map (OSM) database.
Class: linear
Derived Covariates:
cls, dst,

class       : SpatialLinesDataFrame 
nfeatures   : 46 
extent      : 963645, 968343, 7986156, 8004061  (xmin, xmax, ymin, ymax)
coord. ref. : NA 
nvariables  : 7

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Other roads (OSM), 2017

Folder: Roads
File Name: OtherRoads.shp
Source: Open Street Map, Downloaded 2017-08-21, http://extract.bbbike.org/
Description: These data were downloaded as part of a per-country package of data layers made availalble as shapefiles through the http://extract.bbbike.org website, extracted from the Open Street Map (OSM) database.
Class: linear
Derived Covariates:
cls, dst,

class       : SpatialLinesDataFrame 
nfeatures   : 999 
extent      : 953114, 968847, 7975168, 8001579  (xmin, xmax, ymin, ymax)
coord. ref. : NA 
nvariables  : 7

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Points of Interest Locations (OSM), 2017

Folder: Points
File Name: Points.shp
Source: Open Street Map, Downloaded 2017-08-21, http://extract.bbbike.org/
Description: These data were downloaded as part of a per-country package of data layers made availalble as shapefiles through the http://extract.bbbike.org website, extracted from the Open Street Map (OSM) database.
Class: point
Derived Covariates:
cls, dst,

class       : SpatialPointsDataFrame 
nfeatures   : 186 
extent      : 957571, 972412, 7978794, 7998713  (xmin, xmax, ymin, ymax)
coord. ref. : NA 
nvariables  : 4

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Rivers (OSM), 2017

Folder: Wtrways
File Name: Waterways.shp
Source: Open Street Map, Downloaded 2017-08-21, http://extract.bbbike.org/
Description: These data were downloaded as part of a per-country package of data layers made availalble as shapefiles through the http://extract.bbbike.org website, extracted from the Open Street Map (OSM) database.
Class: linear
Derived Covariates:
cls, dst,

class       : SpatialLinesDataFrame 
nfeatures   : 50 
extent      : 954030, 968115, 7973455, 8003620  (xmin, xmax, ymin, ymax)
coord. ref. : NA 
nvariables  : 4

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Natural zones (OSM), 2017

Folder: Natural
File Name: natural.shp
Source: Open Street Map, Downloaded 2017-08-21, http://extract.bbbike.org/
Description: These data were downloaded as part of a per-country package of data layers made availalble as shapefiles through the http://extract.bbbike.org website, extracted from the Open Street Map (OSM) database.
Class: polygon
Derived Covariates:
cls, dst,

class       : SpatialPolygonsDataFrame 
nfeatures   : 57 
extent      : 953552, 968244, 7973036, 8003854  (xmin, xmax, ymin, ymax)
coord. ref. : NA 
nvariables  : 3

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Railways (OSM), 2017

Folder: Railways
File Name: railways.shp
Source: Open Street Map, Downloaded 2017-08-21, http://extract.bbbike.org/
Description: These data were downloaded as part of a per-country package of data layers made availalble as shapefiles through the http://extract.bbbike.org website, extracted from the Open Street Map (OSM) database.
Class: linear
Derived Covariates:
cls, dst,

class       : SpatialLinesDataFrame 
nfeatures   : 52 
extent      : 957479, 968780, 7973591, 7987177  (xmin, xmax, ymin, ymax)
coord. ref. : NA 
nvariables  : 3

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Built-up density 2005

Folder: Built
File Name: MDG_TOA_2005_DENS.tif
Source: MAUPP project: http://maupp.ulb.ac.be/
Description: Fusion of SAR and optical data
Class: raster
Derived Covariates:
,

class       : RasterBrick 
dimensions  : 316, 270, 85320, 1  (nrow, ncol, ncell, nlayers)
resolution  : 100, 100  (x, y)
extent      : 952029, 979029, 7972714, 8004314  (xmin, xmax, ymin, ymax)
coord. ref. : +proj=utm +zone=38 +south +datum=WGS84 +units=m +no_defs +ellps=WGS84 +towgs84=0,0,0 
data source : D:\APRF\RF\data\TOA\Built\Derived\built.tif 
names       : built 
min values  :     0 
max values  :     1 

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Built-up density 2000

Folder: Bu1
File Name: MDG_TOA_2000_DENS.tif
Source: MAUPP project: http://maupp.ulb.ac.be/
Description: Fusion of SAR and optical data
Class: raster
Derived Covariates:
,

class       : RasterBrick 
dimensions  : 316, 270, 85320, 1  (nrow, ncol, ncell, nlayers)
resolution  : 100, 100  (x, y)
extent      : 952029, 979029, 7972714, 8004314  (xmin, xmax, ymin, ymax)
coord. ref. : +proj=utm +zone=38 +south +datum=WGS84 +units=m +no_defs +ellps=WGS84 +towgs84=0,0,0 
data source : D:\APRF\RF\data\TOA\Bu1\Derived\bu1.tif 
names       : bu1 
min values  :   0 
max values  :   1 

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Built-up density 1995

Folder: Bu2
File Name: MDG_TOA_1995_DENS.tif
Source: MAUPP project: http://maupp.ulb.ac.be/
Description: Fusion of SAR and optical data
Class: raster
Derived Covariates:
,

class       : RasterBrick 
dimensions  : 316, 270, 85320, 1  (nrow, ncol, ncell, nlayers)
resolution  : 100, 100  (x, y)
extent      : 952029, 979029, 7972714, 8004314  (xmin, xmax, ymin, ymax)
coord. ref. : +proj=utm +zone=38 +south +datum=WGS84 +units=m +no_defs +ellps=WGS84 +towgs84=0,0,0 
data source : D:\APRF\RF\data\TOA\Bu2\Derived\bu2.tif 
names       : bu2 
min values  :   0 
max values  :   1 

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