Preliminary Survey :
N <- 100
M = 900
Mbar <- M/N
f <- c(3/6, 2/6, 1/2, 1/2, 2/2, 1/2, 1/2, 0/2, 6/8, 0/2, 0/2, 8/8, 7/8, 4/4, 4/4, 4/4, 2/4, 1/6, 1/10, 2/4, 6/10, 6/10, 4/8, 8/12)
mi <- c(6, 6, 2, 2, 2, 2, 2, 2, 8, 2, 2, 8, 8, 4, 4, 4, 4,6,10,4,10, 10,8,12)
ai <- c(3, 2, 1, 1, 2, 1, 1, 0, 6, 0, 0, 8, 7, 4,4,4,2,1,1,2,6,6,4,8)
mbar <- mean(mi)
phat_per <- ai/mi
phat <- mean(phat_per)
# est variance :
sp2 <- sum((ai - phat*mi)^2)/(length(mi)-1)
B <- .1 # off by 5 pct : bound-of-err
D <- ((B^2)*mbar^2)/4
n_est <- (N*sp2)/(N*D + sp2)
n_est <- ceiling(n_est) #round to nxt whole
Drawing Sample :
set.seed(123)
d1_samp <- sample(1:100, 30)
d1_samp |> as.data.frame() # True Order
## d1_samp
## 1 31
## 2 79
## 3 51
## 4 14
## 5 67
## 6 42
## 7 50
## 8 43
## 9 97
## 10 25
## 11 90
## 12 69
## 13 57
## 14 9
## 15 72
## 16 26
## 17 7
## 18 95
## 19 87
## 20 36
## 21 78
## 22 93
## 23 76
## 24 15
## 25 32
## 26 84
## 27 82
## 28 41
## 29 23
## 30 27
d1_samp |> as.data.frame() |> dplyr::arrange(d1_samp)
## d1_samp
## 1 7
## 2 9
## 3 14
## 4 15
## 5 23
## 6 25
## 7 26
## 8 27
## 9 31
## 10 32
## 11 36
## 12 41
## 13 42
## 14 43
## 15 50
## 16 51
## 17 57
## 18 67
## 19 69
## 20 72
## 21 76
## 22 78
## 23 79
## 24 82
## 25 84
## 26 87
## 27 90
## 28 93
## 29 95
## 30 97