Confidence Interval for Proportions (continued): Learn It 3

  • Calculate a confidence interval and explain what it means.
  • Recognize common misinterpretations of confidence intervals.

Interpretation of a confidence interval

As we simulated finding confidence intervals, we learned that a chosen level of confidence is associated with the method used to create the interval and not the likelihood that an individual interval contains the population proportion.

This means that any time we provide a statement to interpret a confidence interval’s meaning, we should state that the confidence level is a measure of our confidence in the method.

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The interpretation of a confidence interval depends on the confidence level. For example, using a [latex]95\%[/latex] confidence level, the interpretation would be:
We can be [latex]95\%[/latex] confident that the interval from ___ to ___ captures the true population proportion of _______.