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### chi squared test or Z test? [duplicate]

I have an outcome from a biological experiment, where I have counted the number of dead cells upon a mutation. For example, in once case - out of 120 cells we saw 16% of the dead cells, but our ...
483 views

### Test of proportions or chi-squared? [duplicate]

These data are from an A/B test of free trials to conversion. Someone can sign up for a 30 day free trial of the product. If they like it they stay on and become paying customers. By default (A), when ...
2k views

### At What Level is a $\chi^2$ test Mathematically Identical to a $z$-test of Proportions?

BACKGROUND: Skip safely - it's here for reference, and to legitimize the question. The opening of this paper reads: "Karl Pearson’s famous chi-square contingency test is derived from another ...
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### Assessing A/B test results using Python

Problem's setting Assume having results of an A/B test. You let you users experience two variants of your website and you counted how many converted: ...
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### Difference estimate & confidence intervals for $\chi^2$ test between 2 proportions

I am using a chi-sq test between two proportions (http://statistic-on-air.blogspot.com/2009/07/comparison-of-two-proportions.html). I am using this over the z-test for proportions because I do not ...
282 views

### Can I use a two proportion z-test?

I have a response, "Satisfaction" that goes on a scale from 0-10 (where 0=dissatisfied and 10= very satisfied), and I have a predictor variable that also uses the same scale. I recoded the response so ...
318 views

### Appropriate Correction for 2 proportion test? --with example--

Below is an example of frequency data between observed and expected proportions. Can I simply run a 2-Proportion z test here? Or, would I be violating assumptions? If I were to run dozens of z tests (...
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### Appropriate test for proportion data

I have two independent groups A and B. Each participant is given 5 questions to solve and his/her answer is evaluated as correct or incorrect. However, participants can skip questions, so the number ...
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### Confusion about z-test and chi square test on a very basic example

I am confused with the difference between z-test and chi square test. In book Agresti 2007 An introduction to categorical data analysis, page 9, the author had an example of testing Do a majority ...
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### What statistical test do I use for differences in proportions?

I have two groups of samples with a proportion of mutations in each sample being a particular type (the proportions are represented as a fraction of 1). How to I check if that type of mutation is ...
111 views

### How to process Binomial-Binomial data on SPSS for hypothesis testing?

There are 2 groups of 100 pregnant women: the first are malnourished and the second are well-nourished. A COHORT research is being done on them to determine if malnutrition is a risk factor for low ...