BIOS 664
Cluster Sampling:
One and Two Stage Sampling
(Unequal-Sized Clusters)
1
Presentation #5
Lecture Notes: Section 7
2
A Population with Unequal-Sized Clusters
Population
(x,y)11
(x,y)12
(x,y)21
Notes for Presentation File # 6
Slide 27
Procedure to select c 2 independent systematic samples:
1. Choose (with replacement) c independent random starts (numbers), R1 , . . . , Rc , between 1 and ck
BIOS 664
Systematic Sampling
1
Presentation #6
Lecture Notes: Sections 8 and 7.4.8
2
Systematic Sampling of
Individual Population Members
A method of equal probability list sampling
Population members
BIOS 664
Developing a Sample Design
1
Presentation #7
2
Some General Rules
(1) Talk in language the client can understand.
(2) Be honest with the client.
(3) Consider all sources of survey error.
3
So
BIOS 664
STRATIFIED SAMPLING
1
Presentation #3
Lecture Notes: Section 5
2
What is Sampling Stratification?
Process
of dividing set of units to be
sampled into subgroups called strata;
Each
unit is a
BIOS 664
SIMPLE RANDOM
SAMPLING
1
Presentation #2
Lecture Notes: Section 4
2
Sampling Theory
Accounts for the statistical effects of
inference to a finite population from a
sample
Effects of nonsampl
Variance Estimation: Paired Selection Model (Odd n0 )
Select one of the elements in your sample and include it again in your sample.
Example sample: S1 = cfw_1, 2, 3 randomly select one of the 3 eleme
BIOS 664
Cluster Sampling:
One and Two Stages
(With Equal-Size Clusters)
1
Presentation #4
Lecture Notes: Section 6
2
Cluster Sampling vs. SRS Sampling
Discussed Up Until Now
Notes:
SRS assumes that