30 questions linked to/from Misunderstanding a P-value?
463k views

What is the meaning of p values and t values in statistical tests?

After taking a statistics course and then trying to help fellow students, I noticed one subject that inspires much head-desk banging is interpreting the results of statistical hypothesis tests. It ...
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Am I taking crazy pills here or this A/B testing tool's documentation dead wrong?

In the documentation here for a popular A/B testing they say, For example, if you run an A/B testing experiment with a significance level of 95%, this means that if you determine a winner, you ...
51 views

Interpretation of the D-statistic from 2-sample KS-tests

I've been using the two sample Kolmogorov-Smirnov test to compare observations from 2018 vs observations from 2019. I heard from my co-worker that you can interpret the D-statistic as the magnitude ...
7k views

interpreting confidence intervals in t.test

I'm trying to run a t-test using t.test() but am confused about the p-value and confidence interval. Looking at the output I see a p-value of ~0.03. That leads me ...
15k views

Can p-value be greater than 1?

Say I perform Student's t-test: can the p-value be greater than 1? The reason I ask this is that, some say that the p-value is the probability that we will have a Type I error and I would like to ...
2k views

What is the relationship between $p$ values and Type I errors [duplicate]

In hypothesis testing we set an accepted level of Type I error probability $\alpha$ and observe whether a sample statistic is equally likely or less likely to be observed if the null hypothesis was ...
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Why do we use the chi-squared test to test independence of 2 categorical variables?

I sometimes use the chi-squared test to test the independence of categorical variables. I know how to do the test but don't know the underlying concepts and details. So, I was wondering about the ...
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Probability that Null Hypothesis is True

So, this may be a common question, but I’ve never found a satisfactory answer. How do you determine the probability that the null hypothesis is true (or false)? Let’s say you give students two ...