Statistical Analysis Stack Exchange
Statistical Analysis Stack Exchange

Questions tagged [permutation]

31 questions
18
votes
3 answers

Finding most likely permutation

[Hoping that this is the right Stackexchange site; inspired from a true story seen at work] Joe has a measuring instrument and $n$ objects to be measured (say, a scale and $n$ weights). He measures each one, obtaining a list of measurements…
GioMott
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7
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1 answer

Probabilities arising from permutations

Certain interesting probability functions can arise from permutations. For example, permutations that are sorted or permutations that form a cycle. Inspired by the so-called von Neumann schema given in a paper called "On Buffon machines and numbers"…
Peter O.
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1 answer

Probability of n persons picking multiple numbers from N numbers, that all choices are different

Given $N$ distinct numbers, $n$ persons each picks $x_i > 0$ numbers, what is the probability $P$ of them all picking different numbers? The limiting case of $n > N$ is trivial, $P = 0$. Same for $\sum_{i=1}^n x_i > N$. This question was inspired by…
Isabella
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3
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1 answer

Adjusting P values for multiple comparisons using permutation tests

I have a number of continuous predictors (biomarker measurements) which I would like to test for association with a binary outcome variable (disease status), adjusting for multiple comparisons. As some of my predictors are correlated, I understand…
kubato
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2
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1 answer

Can I use a permutation test to test the null hypothesis ''The difference between two groups is X''?

From what I read on permutation test, the null hypothesis is usually that there is no difference between the two groups. I want to test if the difference between the mean of the two groups is $\theta$ ($H_0 : \mu_2 - \mu_1 = \theta$). Can I use a…
Capucine25
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2
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What does it mean to "permute" a predictor in the context of random forest?

I am reading the vignette for the R package randomForestExplainer. There the result accuracy_decrease (classification) is defined as mean decrease of prediction accuracy after X_j is permuted What does it mean "permuted" in this context? How is a…
robertspierre
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2 answers

Probability that Secret Santa arrangement will result in perfect pairings for couples

4 couples, 8 people total, participate in a Secret Santa gift exchange. Call the people A, B, C, D, E, F, G, H. Assume A+B are a married couple. Likewise, assume C+D, E+F, and G+H are all couples. All 8 people put their names on a piece of paper…
John L
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2
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1 answer

All combinations for a King and Queen (coed) 2's Tournament Pool Sheet (N girls and N guys)

Ok so I have N girls and N guys. I need to create a 2's beach volleyball coed tournament (also known as King and Queen style). I want a list (like Joe and Jill versus Donald and Melania...etc.) of all possible unique games, given the following…
Millemila
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Interpretation of the adjusted rand-index

I'm trying to understand the adjusted Rand index for a metric review that I'm doing. I found this question most helpful so far: Calculating the adjusted rand index? https://en.wikipedia.org/wiki/Rand_index I think I have a fairly good grasp of the…
boomkin
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Probability that Secret Santa arrangement for couples will result in perfect pairings

4 couples, 8 people total, participate in a Secret Santa gift exchange. Call the people A, B, C, D, E, F, G, H. Assume A+B are a married couple. Likewise, assume C+D, E+F, and G+H are all couples. All 8 people put their names on a piece of paper and…
John L
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0
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How to understand embedding dimension in permutation entropy when checking predictabilty in electric load data?

I am predicting electric load data with different deep learning models and I am trying to define the predictability of the data. So far I came across the permutation entropy (PE) as a measurement for the complexity of the data with a normalized PE…
ap3
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0
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1 answer

effect size for pairwise permutation

I am reading a paper that is using permutations to compare the means of two different treatment groups (a nutrition study, took minimum - maximum) that have low sample sizes, and so the groups are not normal, despite any transformation. Makes sense…
Michael
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0
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1 answer

Random samples within the Central Limit Theorem - why select with permutation with repetition?

"The central limit theorem states that if you have a population with mean μ and standard deviation σ and take sufficiently large random samples from the population with replacement, then the distribution of the sample means will be approximately…
Peiran Yu
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0
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2 answers

Given 9 coat hangers (3 groups), what's the probability

If I had 9 coat hangers (for example: 4 green, 3 blue and 2 red), what would be the probability of the first four being [green, green, blue, blue], if I just chuck the coat hangers into the wardrobe at random? I have a feeling this is a permutations…
Canada
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0
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Disagreement regarding the role of permutation/randomization/shuffling in permuation testing between two populations

A colleague and I recently got into a conversation/disagreement regarding permutation testing (e.g. for comparing the mean value of two populations). While i thought i had a fairly good understanding of it, the fact that i cannot convince him (or…
MaskedCucumber
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