What is a Systematic Sample?
A systematic sample is a sampling method used to select a subset of members from a larger population. This is done in a specific and structured way, allowing the researcher to gather data from a representative sample while still minimizing the amount of time and resources required. Systematic sampling is used in a variety of fields, including marketing, sociology, and economics. It is a type of probability sampling, meaning that each member of the population has an equal chance of being included in the sample.
How Does Systematic Sampling Work?
Systematic sampling works by selecting members from the population at regular intervals. This can be done by selecting every nth member from the population, where n is determined by the researcher. For example, if the researcher wanted to select every 10th member from a population of 100, they would start by selecting the 10th member, then the 20th member, the 30th member, and so on until the 100th member was selected. It is important to note that in order to properly use systematic sampling, the population must be listed in some kind of order. This could be in alphabetical order, by age, or by any other variable that can be used to organize the population.
Examples of Systematic Sampling
Systematic sampling is used in many different research contexts. Here are a few examples:
- In a marketing survey, a researcher might select every 5th customer from a list of customers in order to get a representative sample.
- In a political poll, a researcher might select every 10th voter from a list of registered voters in order to get a representative sample.
- In a medical study, a researcher might select every 15th patient from a list of patients in order to get a representative sample.
Advantages and Disadvantages of Systematic Sampling
Systematic sampling has several advantages:
- It is easy to implement and calculate.
- It is less time consuming than other sampling methods.
- It yields a representative sample.
However, systematic sampling also has some disadvantages:
- It is vulnerable to selection bias if the population is not listed in a random order.
- It is not suitable for populations with unknown sizes.
Conclusion
Systematic sampling is a useful sampling method that can be used to select a representative sample from a larger population. However, it is important to remember that it is vulnerable to selection bias if the population is not listed in a random order, and it is not suitable for populations with unknown sizes.
References
- https://www.statisticshowto.datasciencecentral.com/systematic-sampling/
- https://www.qualtrics.com/blog/what-is-systematic-sampling/
- https://www.investopedia.com/terms/s/systematicsampling.asp