Sampling

Question 1

Who are the target population?

Answer 1

The large group of people who are the focus of the researcher’s interest, from which a smaller sample are drawn

Question 2

What is a sample?

Answer 2

A group of people who take part in a research investigation. The sample is drawn from a population and is presumed to be representative of that population

Question 3

What is bias in sampling?

Answer 3

When certain groups are over or under represented within the sample selected. This limits the extent to which generalisations can be made to the target population

Question 4

Generalisation

Answer 4

The extent to which findings and conclusions from a particular investigation can be broadly applied to the target population. This is possible if the sample if the sample of p’s is representative of the target population

Question 5

Random sampling

Answer 5

When all members of the target population have an equal chance of being selected. A list of all members of the target population is obtained, all the names on the list are assigned a number and the sample is selected using a random number generator

Question 6

Systematic sampling

Answer 6

When every nth member of the target population is selected. A sampling frame (list of people in the target population organised in some way eg. Alphabetically) is produced, a sampling system is determined (eg. Every 3rd person). The researcher works through the sampling frame until the sample is complete

Question 7

Stratified sampling

Answer 7

Where the composition of the sample reflects the proportions of people in certain strata within the population. The researcher identifies the strata that make up the population, representative proportions are worked out and the participants that make up each stratum are selected using random sampling

Question 8

Opportunity sampling

Answer 8

Selecting anyone who happens to be willing and available. The researcher simply asks whoever is around

Question 9

Volunteer sampling

Answer 9

Where participants select themselves to be part of the sample (self-allocation). The researcher may place an advert in a newspaper

Question 10

Evaluation of random sampling

Answer 10

• Potentially unbiased (confounding or extraneous variables equally divided between groups, enhancing internal validity)
• Difficult (a complete list of the target population must be obtained)
• Time consuming
• Potentially unrepresentative

Question 11

Evaluation of systematic sampling

Answer 11

• Objective/ unbiased
• Time consuming
• P’s may decide not to volunteer
• Potentially unrepresentative

Question 12

Evaluation of stratified sampling

Answer 12

• Representative (makes generalisation of findings possible)
• Difficult
• Still potentially unrepresentative

Question 13

Evaluation of opportunity sampling

Answer 13

• Convenient
• Cheap
• Fast
• Researcher bias
• Unrepresentative (certain areas)

Question 14

Evaluation of volunteer sampling

Answer 14

• Easy
• Fast
• Engaged participants
• Volunteer bias (please u or screw you)