Sampling

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Questions and Answers

What is the primary purpose of conducting a sample from a population?

To include every individual in the study

To ensure convenient data collection

To eliminate any selection bias

To represent the entire population accurately (correct)

Which sampling method involves dividing the population into strata before sampling?

Stratified random sampling (correct)

Quota sampling

Systematic sampling

Simple random sampling

What can result from using a convenience sampling method?

Increased generalizability of results

A sample that is biased (correct)

A highly representative sample

Lower sampling costs

Which of the following statements regarding probability sampling is true?

The population must be known to establish a sampling frame. Signup and view all the answers

What might happen if a sampling method leads to selection bias?

Generalization of findings could be flawed. Signup and view all the answers

In which sampling method is every kth element selected?

Systematic sampling Signup and view all the answers

How does increasing the sample size affect the representativeness of the sample?

It increases the likelihood of obtaining a representative sample. Signup and view all the answers

Which of the following describes a limitation of simple random sampling?

It may not always be feasible. Signup and view all the answers

What is the most accurate definition of the term 'population' in research?

The entire set of individuals of interest Signup and view all the answers

What is one of the main challenges when conducting surveys in high schools regarding student attitudes towards searches?

Choosing participants without bias Signup and view all the answers

What is the key characteristic of proportionate random sampling?

It reflects proportions of different groups in the population. Signup and view all the answers

Which sampling technique is best used with large populations when sampling at a group level?

Cluster sampling Signup and view all the answers

What is one major disadvantage of convenience sampling?

It may lead to bias in the sample. Signup and view all the answers

In multistage sampling, what is the first step?

Identify clusters within the population. Signup and view all the answers

Which type of sampling uses referrals from initial participants to gather more subjects?

Snowball sampling Signup and view all the answers

What is a potential advantage of nonprobability sampling methods?

They require less time and money. Signup and view all the answers

What distinguishes quota sampling from stratified sampling?

Quota sampling does not involve random selection. Signup and view all the answers

What could be a consequence of using convenience sampling?

Lack of a clear sampling methodology. Signup and view all the answers

What does cluster sampling facilitate in research methodology?

Cost-effective access to broad populations. Signup and view all the answers

What is the main objective of using probability sampling methods?

To obtain a representative sample of the population. Signup and view all the answers

Study Notes

Population and Samples

Populations are the entire set of individuals that a study is interested in.
Samples are a subset of individuals selected from a population.
Samples are intended to represent the population.
Not everyone in a population can participate in a study, therefore samples are used.

Generalisation

Generalization applies results from a sample to a population.
The accuracy of generalisation depends on how representative the sample is.
Selection bias occurs when a sampling method leads to a biased sample.

Sampling Methods

There are two main types of sampling methods: probability and nonprobability sampling.

Probability Sampling

In probability sampling the probability of any individual being selected is known.
This is possible when the population is known, and a sampling frame is established.
While probability sampling is random, the sample may not be representative.
Larger sample sizes increase the likelihood that the sample resembles the population.

Simple Random Sampling

Every member of the population has an equal chance of being selected.
Simple random sampling reduces systematic bias.
This method does not guarantee a representative sample.
Simple random sampling can be difficult, time consuming, and even impossible.

Systematic Sampling

Every kth member of the population is selected.

Stratified Random Sampling

The population is divided into strata (groups).
A random sample is drawn from each stratum.
This method increases the chances of a representative sample but may underrepresent or overrepresent some strata.

Proportionate Random Sampling

The proportions of different groups in the population are reflected in the sample strata.
This method increases the chance that the sample is representative.

Cluster Sampling

This method is used with large populations.
Sampling is done at the group level instead of the individual level.
Groups are randomly sampled.

Multistage Sampling

Groups are identified and randomly sampled.
Individuals from within the selected groups are then randomly sampled.
Multiple stages may be needed.

Nonprobability Sampling

The probability of any individual being selected is unknown.

Convenience Sampling

Participants are selected because they are readily available.
This method is used when time and money are limited and may be the only possible method.
It is difficult to determine if, and how, the sample is biased.

Snowball Sampling

Participants are asked to refer others.

Quota Sampling

A nonrandom method that resembles stratified sampling, but without random sampling.

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Description

Explore the foundations of population and samples in statistics with this quiz. Understand the key concepts of generalization and discover different sampling methods, including probability and nonprobability sampling. Enhance your comprehension of how these methods impact research results.