Package 'geodetector'

Title: Stratified Heterogeneity Measure, Dominant Driving Force Detection, Interaction Relationship Investigation
Description: Spatial stratified heterogeneity (SSH), referring to the within strata are more similar than the between strata, a model with global parameters would be confounded if input data is SSH. Note that the "spatial" here can be either geospatial or the space in mathematical meaning. Geographical detector is a novel tool to investigate SSH: (1) measure and find SSH of a variable Y; (2) test the power of determinant X of a dependent variable Y according to the consistency between their spatial distributions; and (3) investigate the interaction between two explanatory variables X1 and X2 to a dependent variable Y (Wang et al 2014 <doi:10.1080/13658810802443457>, Wang, Zhang, and Fu 2016 <doi:10.1016/j.ecolind.2016.02.052>).
Authors: Chengdong Xu [aut, cre], Jinfeng Wang [aut], Yue Hou [ctb], Qian Yin [ctb]
Maintainer: Chengdong Xu <[email protected]>
License: GPL (>= 2.0)
Version: 1.0-5
Built: 2024-10-31 22:25:21 UTC
Source: CRAN

Help Index


CollectData

Description

Including data for neural-tube birth defects (NTD) Y and suspected and environmental factor data, "elevation", "soil type", and "watershed".

Usage

data("CollectData")

Format

A data frame with 185 observations on the following 4 variables.


ecological detector

Description

This function identifies the impact differences between two factors X1 ~ X2.

Usage

ecological_detector(y_column, x_column_nn, tabledata)

Arguments

y_column

The index or field name of explained variable column in input dataset.

x_column_nn

The index or field name of explanatory variable(s)in input dataset.

tabledata

The dataset (dataframe) contains fields of explained variable and explanatory variables.

Value

Results of ecological detector is the significance test of impact difference between two explanatory variables.

Examples

data(CollectData)
ecological_detector("incidence",c("soiltype","watershed"),CollectData)
ecological_detector("incidence",c("soiltype","watershed","elevation"),CollectData)

factor detector

Description

The factor detector q-statistic measures the spatial stratified heterogeneity of a variable Y, or the determinant power of a covariate X of Y.

Usage

factor_detector(y_column, x_column_nn, tabledata)

Arguments

y_column

The index or field name of explained variable in input dataset.

x_column_nn

The index or the field name(s) of explanatory variable(s) in input dataset.

tabledata

The dataset (dataframe) contains fields of explained variable and explanatory variables.

Value

Results of factor detector include q statistic and the corresponding p value.

Examples

data(CollectData)
factor_detector("incidence","soiltype",CollectData)
factor_detector(1,2,CollectData)
factor_detector (1,c(2,3,4),CollectData)
factor_detector ("incidence",c("soiltype","watershed"),CollectData)

interaction detector

Description

This function reveals whether the risk factors X1 and X2 (and more X) have an interactive influence on a disease Y.

Usage

interaction_detector(y_column, x_column_nn, tabledata)

Arguments

y_column

The index or field name of explained variable in input dataset.

x_column_nn

The index or field name of explanatory variable(s) in input dataset.

tabledata

The dataset (dataframe) contains fields of explained variable and explanatory variables.

Value

Results of interaction detector include the interactive q satistic.

Examples

data(CollectData)
interaction_detector("incidence",c("soiltype","watershed"),CollectData)
interaction_detector("incidence",c("soiltype","watershed","elevation"),CollectData)

risk detector

Description

This function calculates the average values in each stratum of explanatory variable (X), and presents if there exists difference between two strata.

Usage

risk_detector(y_column, x_column_nn, tabledata)

Arguments

y_column

The index or field name of explained variable in input dataset.

x_column_nn

The index or field name of explanatory variable(s) in input dataset.

tabledata

The dataset (dataframe) contains fields of explained variable and explanatory variables.

Value

Results of risk detector include the means of explained variable in each stratum derived from an explanatory variable and the t-test for difference between two strata.

Examples

data(CollectData)
risk_detector("incidence","soiltype",CollectData)
risk_detector(1,2,CollectData)
risk_detector(1,c(2,3,4),CollectData)
risk_detector("incidence",c("soiltype","watershed","elevation"),CollectData)