For instance, a test that can be performed on a variable of ordinal measurement level can also be performed on a variable of interval measurement level, in which case the interval variable is downgraded to an ordinal variable. Note that theoretically, it is always possible to 'downgrade' the measurement level of a variable. One categorical with 2 independent groups Variable types required for the $z$ test for the difference between two proportions : The $z$ test for the difference between two proportions requires the following variable types: Whether a statistical method is appropriate for your data is partly determined by the measurement level of your variables. Approximate $C\%$ confidence interval for $\pi_1 - \pi_2$ĭeciding which statistical method to use to analyze your data can be a challenging task. To compare the $z$ test for the difference between two proportions with other statistical methods, go to Statkat's Comparison tool or practice with the $z$ test for the difference between two proportions at Statkat's Practice question center Contents
The info pages give information about null and alternative hypotheses, assumptions, test statistics and confidence intervals, how to find p values, SPSS how-to’s and more. It is part of Statkat’s wiki module, containing similarly structured info pages for many different statistical methods. This page offers all the basic information you need about the $z$ test for the difference between two proportions. $z$ test for the difference between two proportions