Questions tagged [exact-test]
Statistical tests where the sampling distribution is necessarily exactly correct & not an approximation based on assumptions &/or large sample theory.
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Are there exact conditional tests for testing system of inequalities of Bernoulli means?
I have two independent Bernoulli samples: $\{X_i\}_{i=1}^{n_1}$, $\{Y_i\}_{i=1}^{n_2}$, $X_i \overset{iid}{\sim} Bern(p_1), Y_i \overset{iid}{\sim} Bern(p_2)$. I need to test:
$$H_0: p_1 \ge p_2 \ge 1/...
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Performing "exact" G-tests in R with contingency table samples using `r2dtable` [closed]
I am interested in performing the "exact" versions of G-tests of independence in R with nonparametric table enumeration after having been told that this could help with achieving more ...
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Small-sample binary logit and linear models - response to referees [closed]
Background: This cross-sectional study collected 30 thrombosis samples. We evaluated the presence or absence of MP components (dependent variable), where 24 cases had MP (coded as 1) and 6 cases did ...
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What is the information in an exact p-value?
Consider the following two statistical principles: 1) an exact test's $p$-value gives the exact frequency with which the observed random sample appears by chance, i.e., under a true null hypothesis; ...
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What kind of logrank test is performed by survdiff function in R?
Information added: this question is not duplicate, neither my question nor the question in the link had been solved at all, I added more info to see if you can see the problem
I was trying to ...
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Performing exact tests for small samples
Let $\mathcal{X}$ be a finite set (it has, let's say, ten elements), and $p$ a probability on $\mathcal{X}$. Let $n$ be an integer, that we assume to be small (let's say, $n=10$).
Given an $n$-tuple $\...
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The shortest confidence interval (in the sense of expectation) for two sample t test when variances are unknown and unequal
I have had a question since graduate school. For a given significance level alpha, the test with smallest confidence interval length expectation should be optimal, because it usually also means a ...
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Exact/Approximate Confidence Interval of Parameter Ratio from two Samples of iid Exponential
Suppose 2 independent samples $X_1,...,X_n \sim Exp(\lambda_1)$ and $Y_1,...,Y_m \sim Exp(\lambda_2)$, and are iid within samples.
I am thinking about how to make an exact confidence interval for $\...
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Are exact logistic regression and conditional logistic regression the same?
I have seen these two terms in practice. Are they actually referring to the same method? If not, what is the main difference between the two methods?
Conditional logistic regression is commonly used ...
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Do poisson regression and exact poisson regression only differ in confidence interval?
The point estimates from the two approaches are the same, right?
I plan to use exact Poisson regression for a study, since the events could be sparse after adjusting for a few covariates.
Is there ...
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What are approximate algorithms in hypothesis testing?
I am reading up 'exact test' from Wikipedia, where it says:
when the result of statistical analysis is said to be an “exact test” or an “exact p-value”, it implies that the test is defined without ...
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McNemar exact DP test not running in R [closed]
I am unable to run the provided example (copy/pasted from here):
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exact binomial test with power calculation that excludes the lower limit of a 95% CI
In a regulatory document I see the following statement and wonder how the sample size of 141 subjects is calculated:
A sample size of 141 subjects provides 80% power to exclude a response rate of 12% ...
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Which of the 3 given exact methods of calculating the confidence interval for median is better (correct)?
I want to calculate CI for the median in R. I found a number of packages and functions doing that and noticed something interesting. I think the problem can be generalized to any statistical software. ...
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Single sample t-test variance assumptions for non-normal data
So I understand that a key assumption behind the single sample t-test is that the sample mean is normally distributed. This is true when the data themselves are normally distributed, and it is ...
