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Statistical significance testing

1-sample z-test for a population proportion


Compare a sample proportion with a hypothesised population value. P-values can be calculated for one or two-tailed comparisons and are compared to a specified significance level.

Inputs are:

  • - a sample estimate of the proportion;
  • - sample size for the estimate;
  • - a population estimate for comparison;
  • - specified significance level; and
  • - whether test is one-tailed or two-tailed.

Outputs include:

  • - the sample proportion and asymptotic (normal approximation) confidence limits (based on specified significance level);
  • - z and P values for the difference between the sample proportion and the population estimate and their interpretation;
  • - whether or not z * p values are > 5 (to ensure test validity); and
  • - a plot of the confidence limits for the proportion.


2 recent calculations

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