Page 105 - NGTU_paper_withoutVideo
P. 105

Modern Geomatics Technologies and Applications

          COVID-19 prevalence and identify the factors affecting its severe spread. However, there are also gaps in terms of enough
          knowledge about the spatial patterns of the disease. [16].
             Spatial analysis methods and Geographic Information System (GIS) platforms could provide a wide range of advantages
          for practitioners working in this field.



          2.  Materials and methods

          2.1 Data collection
                 In order to calculate the CIR and CFR values globally, the data of global population, estimation of cumulative total of
          COVID-19 incidence rates, and fatality rates (case/100,000 population) were derived. The population data of 2019 for each
          country was collected from the World Bank [17]. Besides, COVID-19 cumulative total cases and cumulative total deaths until
          January 9, 2021 were obtained from World Health Organization public dashboard [18].
          Cumulative incidence rate (CIR) presents the percentage of the number of people who get sick in a given time period [19].
          Cumulative fatality rate (CFR) demonstrates the percentage of the number of deaths by a certain disease in a specified period
          [20]. After computing the values of CIR and CFR for each country, we entered them into the ArcGIS 10.8 software to continue
          analysing the spatial patterns.

          2.2 Pattern analysis
                 Spatial autocorrelation statistics measure a basic property of geographic data-the extent of their interdependence with
          data at other locations [21].  Moran’ I is a commonly used indicator of spatial autocorrelation [22], which reveals the tendency
          of polygons having similar (linear correlated) values when compared to their neighbours [23]. The value of Moran’s I is
          between -1.0 and +1.0, which is an indicator of the spatial pattern. This analysis defined as: (> 0) clustered, (= 0) dispersed,
          and (< 0) is random distribution. The spatial distribution of COVID-19 CIRs was obtained by the global Moran’s I according
          to the Equation (1) and Equation (2).




                                                   ∑     ∑      =1          
                                                     =1
                                                              ,        
                                               =                                            (1)
                                                   0  ∑   =1        2




                                                           
                                                  = ∑ ∑                                     (2)
                                                              ,  
                                                0
                                                       =1    =1



          Where     is the deviation of an attribute for feature    from its mean (   −   ),     is the spatial weight between features    and   ,
                                                                           ,  
                                                                   
                  
             is equal to the total number of features, and     is the aggregate of all the spatial weights.
                                               0


          2.3 Hot spot analysis
                 Once we conclude that the data is distributed in clusters, we applied Getis-Ord Gi*hot spot analysis, which is based
          on Gi* spatial statistics [24, 25] to find high and low risk areas. Hot spot areas are the ones with the highest values of CIR. For
          positive z-scores derived from the analysis, the clustering of high CIR values is more intense (hot spots). However, if the z-
          scores are negative, the area considered as cold spots [26]. Getis-Ord Gi*hot spot analysis is calculated based by comparing the
          local sum of the value of each location (country) and those of its neighbours to the sum of all feature values. It is calculated as
          follows:


                                                                                                               2
   100   101   102   103   104   105   106   107   108   109   110