I am interesting in calculating sample size for a descriptive design, quantitative research method study. I will use a nonprobability (snowball) sampling technique. Realizing that a probability statistical technique cannot be used to calculate sample size; it is not statistically justified to use probability statistical measurements (e.g. confidence level) and sample size because the probability of participants' opportunity to participate is unknown. Looking for calculation method and/or literature, studies that may provide insight. Thank you.
Dear Faroq Alshameri
The snowball sampling technique has not any (per se) relations with the sample size. Sample size calculation mostly depends on the population either population or not known (finite or non-finite population). Sample size calculation is the most of the quantitative aspect of the statics rather qualitative.
Determining sample size is a very important issue because samples that are too large may waste time, resources and money, while samples that are too small may lead to inaccurate results. In many cases, we can easily determine the minimum sample size needed to estimate a process parameter, such as the population mean.
If the population is known (sample size calculation with finite population) then you can use any of the following calculators to know the sample size.
1. https://www.surveysystem.com/sscalc.htm
2. https://www.calculator.net/sample-size-calculator.html
3. https://apps.who.int/iris/handle/10665/40062
I mostly used the following online calculator:
4. https://select-statistics.co.uk/calculators/sample-size-calculator-population-proportion/
Some related research paper available on researchgate:
1. Article Sample Size Determination in Health Studies: A Practical Manual.
2. Article Sample size calculation
When You have not any idea about the population ( here in your question i.e. the prevalence of any disease) so you need to use the sample size calculation with a non-finite population.
And in this case,(sample size calculation with non-finite population) you go with the Cochran formula, for this please follow the link:
https://www.researchgate.net/deref/https%3A%2F%2Fwww.statisticshowto.com%2Fprobability-and-statistics%2Ffind-sample-size%2F
or you can visit any other link related to Cochran formula (Sorry I do not know how to type the formula here, so please go to any of the link or just search):
1. https://www.researchgate.net/post/Is_that_possible_to_use_Cochran_formula_sample_size_determination_for_heterogeneous_groups_populations
2. https://www.researchgate.net/post/How_do_I_determine_sample_size_for_each_strata_in_survey2
As per the design of your study determine the sample size for the study.
Please find some of the files (related to sample size calculation) as attached files.
Hope you find all the information useful in the way to determine sample size as the case you have.
Happy researching...
Please follow the link herewith for your kind reference wether it is beneficial.
Article Summary Report of the AAPOR Task Force on Non-probability Sampling
I think you need to know what ES your hoping to obtain for any given sampling frame.
-Matt
- Badges
- Science topic
- Similar topics
- Mathematics
- Statistics
- Statistical Techniques