Sampling - Stats

Question 1

Census advantages

Answer 1

Give a Completely accurate result

Question 2

Census disadvantage

Answer 2

• Time consuming and expensive
• Hard to process large quantity fo data

Question 3

Sample advantages

Answer 3

• less time consuming and more expensive than a census
• fewer pp to respond

Question 4

Sample disadvantages

Answer 4

• data may not be accurate
• may not be large enough to give info of small sub groups

Question 5

Simple random sampling

Answer 5

Sample of size has equal chance of being selected - like lottery, calculator, computer etc

• easy and cheap for small populations
• not suitable for large population size

Question 6

Systematic sampling

Answer 6

The required elements are chosen at regular intervals from an ordered list

• Suitable for large samples and large populations
• can reduce bias if sampling frame is not random

Question 7

Stratified sampling

Answer 7

Population is divided into mutually exclusive strata ( males and females for ex) and a random sample taken from each

• affects population structure
• sampling frame needed

Question 8

Non random sampling - Quota

Answer 8

• interview or researcher selected a sample that reflects the characteristics of the whole population
• small sample which is representative
• must be divided into groups so could be accurately or inaccurate

Question 9

Non random sampling - Opportunity

Answer 9

• taking the sample from people who are variable at time of study that is carried out and fit criteria
• easy to carry out
• Highly dependent on individual researcher