# W2 - Sampling Flashcards

1
Q

Where do you draw your sample from?

A

Population of interest

2
Q

What does the type of sampling method used depend on?

A

Research Q

Money + time available to spend on sampling procedure

3
Q

Why sample?

A

Rarely have access to the whole population that were interested in

4
Q

Define a sample

A

Group of participants selected from a larger population

5
Q

Define inference

A

Extent to which the sample characteristics reflect those of the population

6
Q

What are the types of sampling

A

Probability

Non-probability

7
Q

Probability sampling

A

Selecting from a pop where each member has a chance of being selected.

Probability of selection is known.

8
Q

Non-probability sampling

A

Researcher doesn’t know what population size is + doesn’t have access to it.

Probability of selection is UNKOWN.

9
Q

What are the types of probability sampling

A

Simple random

Stratified random

Systematic

Cluster

10
Q

What are the types of non-probability sampling?

A

Convenience

Snowball

11
Q

Simple random sampling

A

All members of pop has equal chance for being selected

12
Q

Problem with simple random sampling

A

Could be unrepresentative of the population

13
Q

How would a sample being “unrepresentative of the population” be minimised?

A

Larger sample groups

14
Q

Strengths to simple random sampling

A

Easy

Large samples likely to be representative

No info needed prior to sampling

15
Q

Weakness to simple random sampling

A

Larger samples often needed = small samples could be unrepresentative

Comparisons between small subgroups may be difficult

16
Q

Stratified random sampling

A

Stratifying pop into groups based on known characteristics.

Sample then drawn from each group

17
Q

Why is a sample drawn from each group made in stratified random sampling?

A

To mirror proportional representation of the pop

18
Q

What are the types of stratified random sampling?

A

Proportionate

Disproportionate

19
Q

Proportionate stratified random sampling

A

Each sample size is directly proportional to the pop size of the entire pop

20
Q

Disproportionate stratified random sampling

A

Each sample size is not proportional to the pop size of the entire pop

21
Q

Strengths of stratified random sampling

A

Fewer people need to be sampled to achieve same representativeness

Can customise sample to be comparable to a wider population

Can make inferences about small subgroups

22
Q

Weaknesses of stratified random sampling

A

Req obtaining info for the particular stratification variables

Becomes difficult if there’s several variables

23
Q

When is systematic sampling typically used?

A

Very large pop

24
Q

How does systematic sampling work?

A

Experimenter selects from an ordered list every 5th, 10th… entry starting from a random position

25
Q

Cluster sampling

What is the sampling unit?

A

Cluster of ppl belonging to a naturally occurring group

i.e geographical

26
Q

Non-probability sampling

Convenience sampling

A

Sample selected due to being accessible to the researcher.

Considered easiest, cheapest + least time consuming.

27
Q

Non-probability sampling

Snowball sampling

When is it usually done?

A

Very small population

Hidden populations, diff for researchers to access

28
Q

Non-probability sampling

Snowball sampling

How does it work?

A

Researcher asks initial participant to ID another pot participant who meets criteria

29
Q

2) Which of the following research design would give us the most confidence in determining causality?

a. Cross-sectional design
b. One group pre- and post-test design
c. Randomised control trial
d. Longitudinal design

A

Randomised control trial

30
Q

A cross sectional study is an example of what type of research design?

A

Observational

31
Q

Which type of experimental design provides the most confidence in determining causality?

A

True experimental