Select a proportionate stratified random sample, where stratification is based on sites and gender

Question

I have three IDBs and this is the number of people registered from each

Site     female  Male  Total
IDB_A     46      14    60
IDB_B     17      23    40
IDB_C     79      21    100
Total     142     58    200

And this is the sample I want to select from each site

Site     female  Male  Total
IDB_A     20      6     26
IDB_B     7       10    17
IDB_C     34      9    43
Total     60     25    85

And I used the following code by creating three different strata (one for each site) and then selected a random sample from each stratum

str1 <- FBF_PDM[FBF_PDM$Sites=="IDB_A",]
str2 <- FBF_PDM[FBF_PDM$Sites=="IDB_B", ]
str3 <- FBF_PDM[FBF_PDM$Sites=="IDB_C", ]

sample1 <- str1[sample(1:nrow(str1), 26, replace = FALSE), ]
sample2 <- str2[sample(1:nrow(str2), 17, replace = FALSE), ]
sample3 <- str3[sample(1:nrow(str3), 43, replace = FALSE), ]

overall <- rbind(sample1, sample2, sample3)

write.table(overall, "overall2.csv", row.names = FALSE, sep = ",")

However, Am struggling to specify the gender (male, female) to be selected from each site.

Hi Saed, the way you have presented your data as text is OK, please don't edit it to include images of data. Thank you. — user438383, Sep 07 '22 at 08:25

score 0 · Answer 1 · answered Sep 07 '22 at 08:59

Using Map you could apply a subsetted sample function to your desired plan. Together with a splited data set by site, provide sample sizes for the respective sex.

plan
#    Site female Male Total
# 1 IDB_A     20    6    26
# 2 IDB_B      7   10    17
# 3 IDB_C     34    9    43
# 4 Total     60   25    85


set.seed(42)  ## you should set a seed here to make it reproducible
samp <- Map(\(x, y, z)
            rbind(
              x[x$female == 1, ][sample(sum(x$female == 1), y), ],
              x[x$female == 0, ][sample(sum(x$female == 0), z), ]
            ), split(dat, dat$site), plan[-4, ]$female, plan[-4, ]$Male)

## check
lapply(samp, \(x) with(x, table(female)))
# $IDB_A
# female
# 0  1 
# 6 20 
# 
# $IDB_B
# female
# 0  1 
# 10  7 
# 
# $IDB_C
# female
# 0  1 
# 9 34

Data:

dat <- structure(list(site = c("IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", 
"IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", 
"IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", 
"IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", 
"IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", 
"IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", 
"IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", 
"IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", 
"IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_A", "IDB_B", 
"IDB_B", "IDB_B", "IDB_B", "IDB_B", "IDB_B", "IDB_B", "IDB_B", 
"IDB_B", "IDB_B", "IDB_B", "IDB_B", "IDB_B", "IDB_B", "IDB_B", 
"IDB_B", "IDB_B", "IDB_B", "IDB_B", "IDB_B", "IDB_B", "IDB_B", 
"IDB_B", "IDB_B", "IDB_B", "IDB_B", "IDB_B", "IDB_B", "IDB_B", 
"IDB_B", "IDB_B", "IDB_B", "IDB_B", "IDB_B", "IDB_B", "IDB_B", 
"IDB_B", "IDB_B", "IDB_B", "IDB_B", "IDB_C", "IDB_C", "IDB_C", 
"IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", 
"IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", 
"IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", 
"IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", 
"IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", 
"IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", 
"IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", 
"IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", 
"IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", 
"IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", 
"IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", 
"IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", 
"IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", 
"IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C", "IDB_C"), female = c(1, 
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 
1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 
0, 0, 0, 0, 0, 0, 0, 0, 0, 0), X = c(-1.80440994496324, -1.12182260635522, 
-0.34792960655914, 1.23890214863198, -0.274197564852279, 0.162380715558193, 
-0.0646069097530627, -0.705237097025142, 1.36219726875099, -1.09651318808332, 
-0.228433518546891, -0.347828080610269, 0.532128619506733, 1.60723456226119, 
0.513814526116594, 1.38237316057303, 0.763097048549903, -0.624584544634111, 
0.0815438004289869, 1.37607911136477, -1.56126578615704, 0.324770660594699, 
-0.156790316952238, 0.877783860734352, 0.750166575180638, 0.30105340384283, 
1.49281111722931, -1.5254938001697, 0.910717558486022, -1.57953202785754, 
0.587716257118581, 0.0896422960007244, 0.96726165694984, 0.0788123529148234, 
-1.56869983648609, -2.00782318401609, 0.540973524238763, -0.0733765981084255, 
-0.571018393558081, -0.311068459853641, -0.671415067101365, -0.157340452080979, 
-0.931305070999869, -1.98300947947013, -0.219599804249378, 1.04527586946239, 
1.87732956629967, 0.00260619595716637, -0.0806699347091655, 0.96298228123987, 
0.0535710165465174, -0.434898408910037, -1.73729725534231, -1.26369559978243, 
0.406308512069273, -1.45965396777976, 1.0484573701547, -1.3464305394502, 
-0.193570558113494, -0.00233595711367605, -0.0128297338671881, 
0.151947321984398, 0.598511131401079, -0.126212437298279, -0.248535565846776, 
0.160327394904622, -0.433641941597269, 1.53741241910027, -2.17024657661608, 
1.02700461929143, -0.248482933189933, 0.422320385832393, 0.987653293639674, 
0.835568172035023, -0.660521859045705, 1.56406949329184, -1.62297593529155, 
0.863896373478988, -0.5116027734362, -1.9173650254454, -1.86581384861995, 
0.245179063439689, 2.22353430190807, 0.273376064144465, 1.13078479452828, 
0.838669374060099, -0.654615277878206, 0.953960978479396, 0.352951465489323, 
0.206599292649613, 1.00111323431025, 0.747451991640276, -0.626574836723139, 
0.395223685936714, -0.892167954045577, 0.630818410091773, -0.432705183284567, 
0.452138644218517, 0.367999045196345, -0.270387489661909, 0.465512617712979, 
0.574356225626969, -0.230699990157411, 1.17224250830245, 1.39270270673312, 
-0.661991255709585, -0.777369206725014, 0.51353857890878, -0.913312238041272, 
-0.449423805250301, 0.802932699103618, -0.573476850981104, -1.92812516784833, 
0.664390833822148, -1.60254022379425, -1.35460025745385, -3.0179326794179, 
0.831237822230063, 0.251097088847344, 0.462293465941329, 0.844792223223237, 
-0.0419715243215621, -1.10557590570003, 0.563775652330874, 1.30336475581967, 
-1.50022093779466, -0.606989235119036, -0.292245065656577, -1.2896833433236, 
0.694105848774699, -0.599181902897119, 1.25690664397164, 0.053508013627363, 
0.728092517671852, 1.56109806821061, 0.26562475359719, 1.07672625920727, 
0.210697931679245, -1.51167352582237, 0.022402259913625, 0.718136206042103, 
0.48945701784227, -0.17388834587827, -1.2176994886684, 0.646398368709462, 
-0.91645602834789, -1.25182344242557, 0.594927718405501, -1.23281066518983, 
0.244364414906138, 0.00277218534359506, -1.32820968602556, 1.17969641183277, 
-0.592804999148929, 1.19997831633667, -0.475033679612135, -0.575057096150816, 
-0.031226024608499, -0.358056995978456, -0.356601077647731, -0.877664383433726, 
-1.21289712517796, 0.613286618687034, -0.806203341462477, -1.3764569299089, 
-0.507847899163547, -0.800935486737338, -2.19278568567007, -0.290937149267675, 
0.167174121160518, 0.294692356485688, 0.392741265420726, -1.00084371300082, 
-0.325727119823434, -1.00834880542884, -0.635431482033766, -1.20984068798734, 
-1.11646380065269, 0.629881162575935, -0.272521570178626, -0.258841168378671, 
1.72955817989149, -0.0583921654073717, -0.537063784608919, 0.74728669616574, 
-0.487257835389733, 1.3729077814795, -0.377672360646221, -0.616152614118394, 
-1.16812505107469, 0.328640358591086, 1.46651062744016, -0.356009545088913, 
0.261467641877431, 0.333328855175731, 1.42219324030954, 0.663876600666173, 
-1.07365515569531, -0.69690177466674, -0.746130456934561)), row.names = c(NA, 
-200L), class = "data.frame")

plan <- read.table(header=TRUE, text='Site     female  Male  Total
IDB_A     20      6     26
IDB_B     7       10    17
IDB_C     34      9    43
Total     60     25    85')

Thanks jay.sf for the answer, I tried to follow your process but I still have a problems. Can you kindly do the sampling for me and share the code if I send you the original dataset? Thanks you very much sir and I really appreciate your effort — Saed Jama, Sep 07 '22 at 10:08
@SaedJama It is not the purpose of this portal that I do your work. The code I provide is simple and works for the sample data I create. You can specify your problems with this code or ask a new question. Cheers! — jay.sf, Sep 07 '22 at 10:20

Select a proportionate stratified random sample, where stratification is based on sites and gender

1 Answers1