# Sample size

**Sample size definition:**

The sample size refers to the number of individual pieces of data collected in a survey. The sample size is important in determining the accuracy and reliability of a survey's findings. In practice, the sample size used is determined based on the expense of data collection, and the need to have sufficient statistical power.**Sample size table:**

In this table, you will find the exact amount of responses you need based on the confidence level or margin of error.The **margin of error**is the range of values above and below the sample statistic is called the margin of error in a confidence interval. The most common values are 1%, 2, 5% and 5%.For example, suppose we wanted to know the percentage of adults that work out weekly. We could calculate a sample size to ensure that our sample estimate will not differ from the true population value by more than 5 percent (the margin of error) 90 percent of the time (the confidence level).A

**confidence level**refers to the percentage of all possible samples that can be expected to include the true population parameter.For example, suppose all possible samples were selected from the same population, then a 95% confidence level would imply that 95% of the confidence intervals would include the true population parameter.

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**Sample size calculator:**

Sample: **377**