spatial stratified heterogeneity test

Spatial stratified heterogeneity test based on geographic detector.

Usage

ssh.test(formula, data, type = "factor", ...)

Arguments

formula: A formula of spatial stratified heterogeneity test.
data: A data.frame or tibble of observation data.
type: (optional) The type of geographical detector,which must be one of factor(default), interaction, risk, ecological.
...: (optional) Specifies the size of the alpha (confidence level).Default is 0.95.

Value

A tibble of the corresponding result is stored under the corresponding detector type.

Author

Wenbo Lv lyu.geosocial@gmail.com

Examples

ssh.test(y ~ x1 + x2,
         tibble::tibble(y = 1:7,
         x1 = c('x',rep('y',3),rep('z',3)),
         x2 = c(rep('a',2),rep('b',2),rep('c',3))))
#> Spatial Stratified Heterogeneity Test 
#>  
#>           Factor detector         
#> 
#> ----------------------------------
#>  variable   Q-statistic   P-value 
#> ---------- ------------- ---------
#>     x2        0.8929      0.03168 
#> 
#>     x1        0.7714      0.07936 
#> ----------------------------------
#> 

ssh.test(y ~ x1 + x2,
         tibble::tibble(y = 1:7,
                        x1 = c('x',rep('y',3),rep('z',3)),
                        x2 = c(rep('a',2),rep('b',2),rep('c',3))),
         type = 'interaction')
#> Spatial Stratified Heterogeneity Test 
#>  
#>          Interaction detector          
#> 
#> ------------------------------------------
#>  Interactive variable      Interaction    
#> ---------------------- -------------------
#>        x1 ∩ x2          Weaken, nonlinear 
#> ------------------------------------------
#> 

ssh.test(y ~ x1 + x2,
         tibble::tibble(y = 1:7,
                        x1 = c('x',rep('y',3),rep('z',3)),
                        x2 = c(rep('a',2),rep('b',2),rep('c',3))),
         type = 'risk',alpha = 0.95)
#> Spatial Stratified Heterogeneity Test 
#>  
#>              Risk detector             
#> 
#> --------------------------------------
#> Variable x1:
#> 
#> |   |x  |y   |z   |
#> |:--|:--|:---|:---|
#> |x  |NA |No  |No  |
#> |y  |No |NA  |Yes |
#> |z  |No |Yes |NA  |
#> --------------------------------------
#> Variable x2:
#> 
#> |   |a   |b   |c   |
#> |:--|:---|:---|:---|
#> |a  |NA  |No  |Yes |
#> |b  |No  |NA  |Yes |
#> |c  |Yes |Yes |NA  |

ssh.test(y ~ x1 + x2,
         tibble::tibble(y = 1:7,
                        x1 = c('x',rep('y',3),rep('z',3)),
                        x2 = c(rep('a',2),rep('b',2),rep('c',3))),
         type = 'ecological',alpha = 0.95)
#> Spatial Stratified Heterogeneity Test 
#>  
#>           ecological detector          
#> 
#> --------------------------------------
#> 
#> 
#> |   |x2 |
#> |:--|:--|
#> |x1 |No |