medScan
A collection of methods for large scale single mediator hypothesis testing. The six included methods for testing the mediation effect are Sobel’s test, Max P test, joint significance test under the composite null hypothesis, high dimensional mediation testing, divide-aggregate composite null test, and Sobel’s test under the composite null hypothesis. Du, Jiacong, et al. “Methods for large‐scale single mediator hypothesis testing: Possible choices and comparisons.” Genetic Epidemiology 47.2 (2023): 167-184.
Install R
from the R Project Site.
Install the remotes
R package with install.packages("remotes")
.
medScan
package.# simulate data under the mixture null
n=10000
u = runif(n,0,1)
z.alpha = z.beta = rep(NA,0)
pi00 = 0.98
pi10 = 0.01
pi01 = 0.01
for(i in 1:n){
if(u[i]<=pi00){
z.alpha[i] = rnorm(1, 0, 1)
z.beta[i] = rnorm(1, 0, 1)
} else if (u[i]<= pi00+pi10){
z.alpha[i] = rnorm(1, 1, 1)
z.beta[i] = rnorm(1, 0, 1)
} else {
z.alpha[i] = rnorm(1, 0, 1)
z.beta[i] = rnorm(1, 1, 1)
}
}
# obtain p-values
obj = medScan(z.alpha = z.alpha, z.beta = z.beta, method = "Sobel")
qqman::qq(obj$pvalues, xlim = c(0,4), ylim = c(0,4), main = "Sobel")
obj = medScan(z.alpha = z.alpha, z.beta = z.beta, method = "MaxP")
qqman::qq(obj$pvalues, xlim = c(0,4), ylim = c(0,4), main = "MaxP")
obj = medScan(z.alpha = z.alpha, z.beta = z.beta, method = "HDMT")
qqman::qq(obj$pvalues, xlim = c(0,4), ylim = c(0,4), main="HDMT")
obj = medScan(z.alpha = z.alpha, z.beta = z.beta, method = "Sobel_comp")
qqman::qq(obj$pvalues, xlim = c(0,4), ylim = c(0,4), main = "Sobel-comp")
obj = medScan(z.alpha = z.alpha, z.beta = z.beta, method = "JT_comp")
qqman::qq(obj$pvalues, xlim = c(0,4), ylim = c(0,4), main="JT-comp")
obj = medScan(z.alpha = z.alpha, z.beta = z.beta, method = "DACT")
qqman::qq(obj$pvalues, xlim = c(0,4), ylim = c(0,4), main="DACT")