Sampling in Social Research it’s type and definition
Lecture by Dr, Sheeba Khalid
SAMPLING IN RESEARCH
What is sampling?
Sampling in Social Research: Sampling is a technique of selecting individual members or a subset of the population to make statistical inferences from them and estimate the characteristics of the whole population. we use Different sampling methods in market research so that they do not need to research the entire population to collect actionable insights. It is also a time-convenient and cost-effective method and hence forms the basis of any research design.
Sampling in Social Research: Types of sampling: sampling methods
Sampling in market action research is of two types – probability sampling and non-probability sampling. Let’s take a closer look at these two methods of sampling.
- Probability sampling: Probability sampling is a sampling technique where a researcher sets a selection of a few criteria and chooses members of a population randomly. All the members have an equal opportunity to be a part of the sample with this selection parameter.
- Non-probability sampling: In non-probability sampling, the researcher chooses members for research at random. This sampling method is not a fixed or predefined selection process. Simple random sampling: One of the best probability sampling techniques that helps in saving time and resources, is the Simple Random Sampling method.
- For example, in an organization of 500 employees, if the HR team decides on conducting team building activities, it is highly likely that they would prefer picking chits out of a bowl.
- Cluster sampling: Cluster sampling is a method where the researchers divide the entire population into sections or clusters that represent a population. This makes it very simple for a survey creator to derive effective inference from the feedback.
- For example, if the United States government wishes to evaluate the number of immigrants living in the Mainland US, they can divide it into clusters based on states such as California, Texas, Florida, Massachusetts, Colorado, Hawaii, etc.
- Systematic sampling: Researchers use the systematic sampling method to choose the sample members of a population at regular intervals. This type of sampling method has a predefined range, and hence this sampling technique is the least time-consuming.
- For example, a researcher intends to collect a systematic sample of 500 people in a population of 5000. He/she numbers each element of the population from 1-5000 and will choose every 10th individual to be a part of the sample (Total population/ Sample Size = 5000/500 = 10).
- Stratified random sampling: Stratified random sampling is a method in which the researcher divides the population into smaller groups that don’t overlap but represent the entire population.
- For example, a researcher looking to analyze the characteristics of people belonging to different annual income divisions will create strata (groups) according to the annual family income. Eg – less than $20,000, $21,000 – $30,000, $31,000 to $40,000, $41,000 to $50,000, etc. By doing this, the researcher concludes the characteristics of people belonging to different income groups. Marketers can analyze which income groups to target and which ones to eliminate to create a roadmap that would bear fruitful results.
How do you decide on the type of sampling to use?
For any research, it is essential to choose a sampling method accurately to meet the goals of your study. The effectiveness of your sampling relies on various factors. Here are some steps expert researchers follow to decide the best sampling method.
- Jot down the research goals. Generally, it must be a combination of cost, precision, or accuracy.
- Identify the effective sampling techniques that might potentially achieve the research goals.
- Test each of these methods and examine whether they help in achieving your goal.
- Select the method that works best for the research.
Difference between probability sampling and non-probability sampling methods
We have looked at the different types of sampling methods above and their subtypes. To encapsulate the whole discussion, though, the significant differences between probability sampling methods and non-probability sampling methods are as below:
|Probability Sampling Methods||Non-Probability Sampling Methods|
|Definition||Probability Sampling is a sampling technique in which samples from a larger population are chosen using a method based on the theory of probability.||Non-probability sampling is a sampling technique in which the researcher selects samples based on the researcher’s subjective judgment rather than random selection.|
|Alternatively Known as||Random sampling method.||Non-random sampling method|
|Population selection||The population is selected randomly.||The population is selected arbitrarily.|
|Nature||The research is conclusive.||The research is exploratory.|
|Sample||Since there is a method for deciding the sample, the population demographics are conclusively represented.||Since the sampling method is arbitrary, the population demographics representation is almost always skewed.|
|Time Taken||Takes longer to conduct since the research design defines the selection parameters before the market research study begins.||This type of sampling method is quick since neither the sample or selection criteria of the sample are undefined.|
|Results||This type of sampling is entirely unbiased and hence the results are unbiased too and conclusive.||This type of sampling is entirely biased and hence the results are biased too, rendering the research speculative.|
|Hypothesis||In probability sampling, there is an underlying hypothesis before the study begins and the objective of this method is to prove the hypothesis.||In non-probability sampling, the hypothesis is derived after conducting the research study.|