sampling Flashcards

(20 cards)

1
Q

What is a sample?

A

A subset, or some part, of a larger population.

Samples are used to draw conclusions about the entire population without needing to collect data from every individual.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Define population in the context of sampling.

A

Any complete group of entities that share some common sets of characteristics.

Understanding the population is crucial for effective sampling.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a population element?

A

An individual member of a population.

Each element contributes to the overall characteristics of the population.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is a census?

A

An investigation of all the individual elements that make up a population.

A census can be resource-intensive and time-consuming.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

List reasons why sampling is often more beneficial than a census.

A
  • Practicality
  • Cost-effectiveness
  • Time-saving
  • Feasibility in large populations
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the target population?

A

The relevant population that should be included for data collection.

Operationally defining the target population helps in identifying ideal data-collection sources.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is a sampling frame?

A

A mechanism for defining which elements from a target population are available for selection.

It is also known as the working population.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is a sampling frame error?

A

Occurs when certain sample elements are not listed or accurately represented in a sampling frame.

This can lead to biased results if important elements are missing.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Define sampling unit.

A

A single element or group of elements subject to selection in the sample.

Sampling units can be individuals, groups, or even entire entities.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

True or False: Non-response error can cause a sample to be less than perfectly representative.

A

True.

Non-response error occurs when certain groups do not participate in the survey.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What differentiates probability sampling from non-probability sampling?

A

Probability sampling has a known, non-zero probability of selection for each member of the population, while non-probability sampling relies on personal judgment or convenience.

This distinction affects the accuracy and reliability of the results.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is random sampling error?

A

A statistical fluctuation that occurs because of chance variations in the elements selected for a sample.

It generally decreases as sample size increases.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Fill in the blank: A _______ error occurs due to imperfect sample design.

A

systematic (non-sampling) error.

This type of error is often more difficult to quantify than random sampling error.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What factors should be considered when determining sample size?

A
  • Required level of accuracy
  • Cost-benefit analysis
  • Population variability
  • Time and budget constraints
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the impact of larger sample sizes on accuracy?

A

Larger sample sizes increase accuracy and decrease random sampling error.

However, the rate of decrease in sampling error slows as sample size increases.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the importance of mobile devices and the Internet in sampling?

A

They change many standard sampling methods, allowing for new ways of collecting data.

Internet surveys can reach broader populations more efficiently.

17
Q

What is respondent-driven sampling?

A

where existing study subjects recruit future subjects from among their acquaintances.

This method can help access hard-to-reach populations.

18
Q

In the context of sampling, what are the key takeaways regarding why sampling is done?

A
  • Pragmatic reasons
  • Accurate and reliable results
  • Cost reduction
  • Feasibility in accessing total population
19
Q

What type of sampling procedure is used when a researcher asks one participant to refer others?

A

Snowball sampling.

This method is useful for reaching hidden populations.

20
Q

What is the main difference between random sampling error and systematic (non-sampling) error?

A

Random sampling error is due to chance fluctuations, while systematic error is due to imperfect sample design.

Understanding these errors is crucial for data interpretation.