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How to Calculate the Sample Size for a Quantitative Study

A sample size is a small group that represents a larger population. In statistics, it is often impossible to actually test an entire population when gathering information. Selecting a sample helps researchers conduct their study in less time with accurate results. Doctoral students will often use these studies in writing a thesis or dissertation. Selecting the correct sample size from a larger population is imperative in order to avoid research and/or inference mistakes. Calculating sample sizes involves the amount of money available to spend on the project.

Instructions

- 1
  Create a budget for the total amount of money allowed for the statistical sampling process.
- 2
  Subtract an amount of money needed to pay for costs not associated with the study. Travel expenses, fees to obtain data and similar costs are just a few examples.
- 3
  Determine the amount of money you need to spend on creating the survey or form sent to the selected sample group.
- 4
  Calculate the sample size using a simple formula. Subtract the money for costs from the budget and divide by the individual survey cost. For example, $1,000 budget less $300 in travel costs with an individual survey cost of $10 results in a sample size of 70.

How to Get a Ph.D. in Statistics

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