s ampling in f ood s ecurity a ssessment kayw zaw tun programme assistant (gis) wfp
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SAMPLING IN FOOD SECURITY ASSESSMENT
Kayw Zaw TunProgramme Assistant (GIS)
WFP
PROBABILITY SAMPLING
Simple random sampling Systematic sampling Stratified sampling Cluster sampling Multi-stage sampling
Non-Probability sampling Purposive samplingConvenience sampling
STRATIFIED (RANDOM) SAMPLING
A A B B B BA A A A C C C C A A C C C C
Divide the population into homogeneous sub-groups.Select sub-samples from each sub-group. (If one selects them in proportion to the size of the sub-group, the sample does need to be weighted later.)Maintains representation with small samples being even when the population is quite large.Ensures representation if the population is highly heterogeneous and some groups might be left out of the sample.
Is cost-effective and time-saving.
Own production(food or cash
crop, livestock, fish farm)
Sales Cash income
Essential non-food expenditure
Employment Cash receipt
s
Food purchases
Food receipts
Household food access
Quantities retained for household’s own use
Trading
Gathering Fishing Hunting
Resource flows
Asset accumulation Non-essential expenditures
Quantities sold to generate income
Sources of food
Income used to purchase
food
Debts incurre
d
Expenditure
Non-agric. productio
n
Sources of
income
= Livelihood activities
Zoning in NRS
Landsat 7ETM +
Land Cover Classification
Agriculture Land and Non-
Agriculture Land
Distribution of River and Stream
Channel
Road Infrastructure
2 Miles Buffer from Coastal
Line
NRS Zones
SAMPLING
Calculation of sample size for Food Security profiling exercises
Calculation for Sample size N= 1.962 x (P)(1-P)
d2
1.96 = 95% confidence interval
P=Estimated prevalence
(50%)
d= desired precision ( 5%)
DEFF=Design effect
(1.5)
HH refusal5%
607
Township: Village-tract… ……………Villages ……. …………… Segment No.……..
Random start number: …………..
Sampling Interval= (total number of households) divided by (total hh to be visited) and then round the result = …………
Sr. of hh
Name of hh head
Name of spouse
# of HH membersSr. No. of sample hh
Remarks
Male Female Total
SYSTEMATIC SAMPLINGA list of individuals/households is numbered.The list is divided into ‘n’ equal sections (‘n’ being sample size).One unit is selected using SRS.Corresponding numbers (one from each) are taken from each section (e.g. if the sixth unit is chosen from the first section, then it should be taken from all the other sections).It is possible to list the population in a meaningful manner (such as putting each county together) and thus ensure samples are taken from each county.
.
THNAK YOU
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