GNGTS 2024 - Atti del 42° Convegno Nazionale

Session 2.2 GNGTS 2024 Second, populaCon, age and gender data in the Facebook dataset was compared with naConal census data collected by local partners. Local partners retrieved the available populaCon data from naConal sources, including populaCon data by age and gender in each country and sub- naConal administraCve units (Oblasts). The collected data were extracted from the latest available populaCon census or equivalent data source (2021 for Uzbekistan, 2020 for Kazakhstan and Kyrgyz Republic, 2019 for Turkmenistan, and 2018 for Tajikistan). Finally, for each Oblast, the Facebook base layer was corrected according to the recent naConal-scale data. This is done under the assumpCon that recent naConal census data is more reliable than global datasets. The difference was greater than 20% in 7 Oblasts of the 4 considered countries. In all regions, the 100-m populaCon grid was corrected proporConally to the esCmated difference with the naConal census data. The correcCon was performed also for a number of ciCes in Kyrgyz Republic, Kazakhstan and Turkmenistan, for which data were available. Gender and age percentages were also corrected based on the naConal data collected aper 2019, when available from country-based data (table 1 only for Kazakhstan). The excepCon of the elder fracCon (greater than 60 years old) was maintained from the Facebook populaCon dataset because the data at naConal scale was only available for different age thresholds (e.g., 70 for Kyrgyz Republic and Uzbekistan, 63 for Kazakhstan). Figure 1 shows a detail of the populaCon exposure dataset provided by the high-resoluCon Facebook dataset and the grid developed at 100m resoluCon in this project (bobom) showing that it matches successfully the building's distribuCon in the aerial image (top). Fig. 1. DistribuCon of the buildings based on an aerial image in a village in Jalal-Abad Oblast, Kyrgyz Republic (top), (bobom) populaCon grid at 20m (Facebook) and 100m resoluCon (orange and yellow dots respecCvely). Country Oblast Total Men Women >60 years old <5 years old Kazakhstan Akmola 1.732.686 831.689 900.996 190.595 138.614