Systematic sampling is a sampling method that addresses
one of the drawbacks of simple random sampling, which is the potential for poor representation
when large portions of the population are excluded from the sample. This drawback is overcome
through the use of systematic sampling, which involves sorting the target population into an
ordered sampling frame and selecting elements at regular intervals within this frame.
To implement systematic sampling, the sampling interval or skip (k) is determined
by dividing the population size by the desired sample size (k = population size/sample size).
The first element is randomly selected from within the first to the kth element in the ordered
list, and then every kth element thereafter is included in the sample. This systematic approach
ensures that the sample is evenly spread across the entire target population.
By using systematic sampling, researchers can achieve a more comprehensive
representation of the population compared to simple random sampling. This method helps prevent
potential biases that may arise from the arbitrary selection of elements in simple random
sampling, particularly when there are distinct patterns or variations within the population.
Systematic sampling ensures that every element in the population has an equal chance of being
selected while providing a systematic and structured process for sample selection.
It is important to note that systematic sampling assumes that there is no
inherent periodicity or pattern within the population that aligns with the sampling interval.
If such patterns exist and align with the sampling interval, systematic sampling may introduce
biases. Researchers should be cautious and evaluate the suitability of systematic sampling in
relation to the specific characteristics and goals of their study.
Overall, systematic sampling is a useful sampling method that provides better
representation and coverage of the target population compared to simple random sampling,
ensuring that the sample is evenly distributed across the entire population.
