Statistical Analysis Stack Exchange
Statistical Analysis Stack Exchange

Questions tagged [bonferroni]

Bonferroni refers to a method of adjustment for multiple comparisons in which the p value is divided by the number of tests. It is more conservative than many other such methods.

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Is the exact value of a 'p-value' meaningless?

I had a discussion with a statistician back in 2009 where he stated that the exact value of a p-value is irrelevant: the only thing that is important is whether it is significant or not. I.e. one result cannot be more significant than another; your…
Mark Ramotowski
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Why aren't multiple hypothesis corrections applied to all experiments since the dawn of time?

We know that we must apply Benjamini Hochberg-like corrections for multiple hypothesis testing to experiments based on a single data set, in order to control the false discovery rate, otherwise all experiments that give a positive result could be…
Kelvin
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What's wrong with Bonferroni adjustments?

I read the following paper: Perneger (1998) What's wrong with Bonferroni adjustments. The author summarized by saying that Bonferroni adjustment have, at best, limited applications in biomedical research and should not be used when assessing…
goro
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Maximum number of independent variables that can be entered into a multiple regression equation

What is the limit to the number of independent variables one may enter in a multiple regression equation? I have 10 predictors that I would like to examine in terms of their relative contribution to the outcome variable. Should I use a bonferroni…
Melissa Duncombe
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Bonferroni or Tukey? When does the number of comparisons become large?

Reading Field's Discovering Statistics Using SPSS (3rd Edition) I was struck by a bit about post-hoc tests in ANOVA. For those wanting to control the Type I error rate he suggests Bonferroni or Tukey and says (p. 374): Bonferroni has more power…
Parbury
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Is Fisher's LSD as bad as they say it is?

When we perform experiments (on small sample sizes (usually the sample size per treatment group is about 7~8)) on two groups, we use a t-test to test for difference. However, when we perform an ANOVA (obviously for more than two groups), we use…
Rover Eye
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How and when to use the Bonferroni adjustment

I have two questions regarding when to use a Bonferroni adjustment: Is it appropriate to use a Bonferroni adjustment in all cases of multiple testing? If one performs a test on a data set, then one splits that data set into finer levels (e.g. split…
user28592
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Sidak or Bonferroni?

I am using a generalized linear model in SPSS to look at the differences in average number of caterpillars (non-normal, using Tweedie distribution) on 16 different species of plants. I want to run multiple comparisons but I'm not sure if I should…
Emily
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Why use Bonferroni over Holm-Bonferroni?

I can see why you might not use a more powerful method, such as the Hochberg method, over the Bonferroni correction, as they may have extra assumptions, such as the independence of hypotheses in this case, but I don't understand why you would ever…
Student's Teapot
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When to correct p-values in multiple comparisons?

I'm afraid that related questions didn't answer mine. We evaluate the performances of >2 classifiers (machine learning). Our Null hypothesis is that performances do not differ. We perform parametric (ANOVA) and non-parametric (Friedman) tests to…
Chris
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p-value adjustment for Local Moran's I statistic (LISA)

I'm working with some exploratory spatial analysis in R using spdep package. I came across an option to adjust p-values of local indicators of spatial association (LISA) calculated using localmoran function. According to the docs it is aimed…
radek
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Bonferroni Correction & machine learning

In psychology studies I learned that we should use the Bonferroni method to adjust the significance level when testing several hypothesis on a single dataset. Currently I am working with machine learning methods such as Support Vector Machines or…
Nikolas Rieble
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Confidence intervals from the Holm-Bonferroni test?

I'm a newcomer in the problem of multiple comparisons. I wonder how to calculate confidence intervals for Holm-Bonferroni method? I know that for Bonferroni method we can just change the confidence level from $1-\alpha$ to $1-\frac{\alpha}{m}$. Does…
Macaronnos
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Post-hoc tests for MANOVA: univariate ANOVAs or discriminant analysis?

I am using a MANOVA test to compare nine different dependent variables (from neuropsychological and neuropsychiatric assessment) between three groups. The output shows a significant influence from GROUP on my variables ($p < .001$). Ofcourse, I am…
TvBalkom
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How to apply multiple testing correction for gene list overlap using R

I have 2 studies looking at the patient response to the same drug. Study 1 found 10,000 genes expressed above the background and 500 of them are differentially expressed and referred to as the drug response signature. Study 2 found 1,000 genes…
user26973
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