S3

Question 1

What does 95% CI mean?

Answer 1

Within which we r 95% confident the population mean lies

Question 2

Advantage of stratified

Answer 2

Rep all groups proportionately

Suitable for large samples

Question 3

Simple Random sampling

Answer 3

Each member of the population has an equal chance of being selected

Question 4

SRS ad

Answer 4

Can analyse result, estimate error
Simple
No bias
Each is included only once

Question 5

Stratified extra ad

Answer 5

Sample large

Question 6

Stratified disad

Answer 6

Overlapping strata

SRS within strata

Question 7

SRS disad

Answer 7

Large

Snaking frame required give e.g.

Question 8

Systematic sampling

Answer 8

Simple

Suitable for large samples

Question 9

Systematic disad

Answer 9

Biased

Only random if the ordered list is truly random

Question 10

Quota ad

Answer 10

Cost kept to a min

Fieldwork done quickly

Question 11

Quota sampling disad

Answer 11

Non random
Non response not recorded
X estimate errors
Interviewer bias

Question 12

How to do systematic to select 50 from 400?

Answer 12

Start with 1-8 say 3
Then select 11
Then 19