Margin of Error

Margin of Error or Confidence Interval is a statistic computed to determine the amount of random sampling error for a sample of data.

This statistic is often expressed as plus or minus (±) of a percentage. For instance, if the data from a sample of 384 observations show a 69% hit rate and we apply a 95 percent confidence level, we would can be 95 percent confident the true proportion in the population is 69% ±4.63%, or between 64% and 74%.

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Sample Size: The total number of individuals in the sample.

Sample Proportion: The proportion in the sample. (Number of specific observations/Total number of observations) %

Confidence Level: The confidence level is the probability an estimate in a sample survey is also true for the population.