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Selective Sampling

What is Selective Sampling?

Selective sampling is the process of picking samples from a larger sample size depending on the survey taker’s or researcher’s assessment. To put it simply, a selective sample is collected based on the needs of the exam, survey, or study for which it will be utilized.

There are synonyms for this sampling like purposive, subjective, or judgmental sampling.

Sampling techniques

  • A standard case– is employed when a researcher or evaluator wishes to investigate a phenomenon that is connected to the parent sample’s typical (average) members.
  • Heterogeneous sampling– a strategy that gathers a diverse variety of viewpoints on your research topic.

In this purposive sampling method, we may search for and generate samples for various viewpoints, ranging from common to uncommon or extreme features of the ‘whole population’ that give a varied variety of examples for an experiment.

  • Homogeneous sampling– a strategy that is opposed to the previous one. A group of persons of the same background or profession will be picked using homogenous sampling.

When researching a certain characteristic, feature, or region of interest, researchers frequently employ homogenous purposive sampling. This is a frequent sort of sampling in survey research – an approach used to explore specific regions of interest.

  • Critical sampling– One information-rich instance is chosen to represent the population via critical case purposive sampling. By researching it, the researcher believes it to provide facts that relate to other comparable circumstances.
  • Extreme sampling– We analyze outliers from a defined norm for a certain event or trend. As a result, we shall choose from the whole sample those who do not meet the standard for an experiment’s criteria. The goal is to determine why such anomalies arise and a pattern to them.
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Self-selection sampling allows us to choose which pieces of data to include in a selection and conduct an in-depth analysis. But it isn’t all. Let’s look at some of the less obvious advantages:

  • Low-cost sample selection strategy. In this case, the researcher selects individuals or data points depending on their knowledge. As a result, if the scientist is accurate, the collection will be precise.
  • Effective with a wide range of populations. However, it works particularly effectively with smaller overall sample size. The researcher may examine all pieces of data for distinguishing characteristics, resulting in superior data.
  • This sampling approach has no randomness. Created samples are well suited to the setting survey.
  • Selective samples make it simple to target particular audiences.
  • The error margin is low since they are chosen based on the qualities that match the criterion.
  • It’s the best way to identify averages in data, which is useful in many investigations.
  • Can generate significant results in real-time while performing human studies since these individuals do have some specialized information about the research issue.


The biggest limitation of purposive sampling is that it is susceptible to analyst bias since researchers make subjective or generic assumptions when selecting participants for their internet questionnaire.

When researchers seek to eliminate as much prejudice as possible, they should employ some type of probability sampling.

Nevertheless, researcher bias is just a significant danger to the credibility of a study when the researcher’s judgments are poorly considered or are not founded on established criteria.

Similarly, it might be challenging for researchers to persuade some that their study is sufficiently representative of the greater population of interest.