The MNAR mechanism assumes that the probability and cause of missingness are unknown to us and lie in the unobserved data. Under this mechanism we generate missing values by looking at each variable's lowest values and replacing them with NA.
Examples
set.seed(123)
data <- gen.mcar(100,rho = c(.15,.25,.12,.45,.34,.54),sigma = c(1,2,1,2),n_vars = 4, na_prob = 0)
mnar_data <- mnar.transform(data,"V1",c("V2","V3"), na_rate = .25)
summary(mnar_data)
#> V1 V2 V3 V4
#> Min. :-2.30917 Min. :-0.3039 Min. :0.03673 Min. :-4.58910
#> 1st Qu.:-0.49385 1st Qu.: 0.3111 1st Qu.:0.38073 1st Qu.:-1.23381
#> Median : 0.06176 Median : 1.0246 Median :0.65188 Median : 0.09614
#> Mean : 0.09041 Mean : 1.3334 Mean :0.85891 Mean : 0.06959
#> 3rd Qu.: 0.69182 3rd Qu.: 1.8039 3rd Qu.:1.26000 3rd Qu.: 1.48147
#> Max. : 2.18733 Max. : 6.1032 Max. :2.39781 Max. : 4.32329
#> NA's :50 NA's :50