Skip to main content

Questions tagged [permutation]

The tag has no usage guidance.

Filter by
Sorted by
Tagged with
0 votes
0 answers
12 views

Probability of chain of events over a finite set of event with no repetition

I'm trying to tackle a problem that I suspect resembles others I'm unfamiliar with. I would love pointers for further reading. The problem is as follows: We have a finite set of actions we can take $\...
Sean's user avatar
  • 1
1 vote
0 answers
16 views

NA for p value of intercept in permutation test through permutes package in R [closed]

I am looking for how FROH (inbreeding level) change with age, island and year are random. I got the following result and got NA for p value of intercept, what might be the cause of it and how to ...
Nitya Shrestha's user avatar
2 votes
0 answers
180 views

Prove that modified RBF function satisfies Mercer conditions

Suppose that I have a modified RBF kernel function. $k(\mathbf{x},\mathbf{y}) = \exp{(-||\mathbf{x}-P\mathbf{y}||^2 })$ where $\mathbf{x},\mathbf{y}$ represent $d$ dimensional inputs and $P$ is the ...
flammmes's user avatar
0 votes
0 answers
16 views

Likelihood ratio exponential family under permutation of parameters

I'm reading "ASYMPTOTIC NORMALITY OF MAXIMUM LIKELIHOOD AND ITS VARIATIONAL APPROXIMATION FOR STOCHASTIC BLOCKMODELS" Bickel et al. 2013. In their proof of Lemma 3, they claim a result and I ...
Josh Willcox's user avatar
4 votes
1 answer
84 views

Order agnostic autoregressive sequence probability

Autoregressive models define the following probability of a sequence $x$ as $p(x)=\Pi p(x_t | x_{<t})$ using the probability chain rule. Then Hoogeboom et al. 2022 state that if we uniformly sample ...
JustBlaze's user avatar
0 votes
0 answers
37 views

how to account for non-independence in the analysis of dissimilarity matrices with restricted PERMANOVA or alternative methods

I am doing a study looking at how bacterial communities on eggshells correlate with species-site and nest stage. We sampled the eggshell bacteria at two sites, with two different host species sampled ...
aq4u's user avatar
  • 1
-1 votes
2 answers
172 views

How many distinct possibilities for the first $k$ elements of a permutation of $n$ items, when some of the items are identical?

Problem If I have to rearrange $n$ items (which some of them are identical), taking the order into account and only selecting the first $k$ items of every permutation, how many permutations do I have ...
georgiem's user avatar
1 vote
1 answer
52 views

Question on permutation and combination

I am having a trouble understanding how to answer the following question and what method to use. The final answer is $415800$ Suppose there are 4 committees A, B, C, and D. 11 candidates are randomly ...
Rudinberry's user avatar
1 vote
0 answers
22 views

How to evaluate whether a treatment effect is significant given variance in measurement

I have two samples I am using to evaluate the effect of a treatment. Group $T$ contains 60 treated objects and their scores and group $C$ contains 60 control objects and their scores. The two groups ...
naveace's user avatar
  • 105
2 votes
1 answer
2k views

Making sense of importance measures offered in Ranger

I have trained a regression forest using the R package ranger. Now I would like to discuss the variable importance measures of the included features. However, I am having difficulties understanding ...
Nerd's user avatar
  • 49
0 votes
0 answers
14 views

Number of possible permutations for N groups from I items where each item is of a different size but group total is fixed across groups

this is my first post. I am not sure how to approach this problem, I would like direction or even an algebraic solution please. I have to sort 70 different sized items out into 12 groups. Each group ...
scattered_dev's user avatar
1 vote
0 answers
113 views

Is this a valid statement according to the de Finetti theorem?

Some background on my problem - Let us consider a discrete memoryless channel (DMC) $W_{Y|X}$ from Alice to Bob. A DMC is a conditional probability distribution over the random variable $Y$ given ...
user1936752's user avatar
1 vote
1 answer
132 views

Bootstrapping or permuting as resampling methods for correlations?

I have many variables ( ~2000 and 320 samples) and I have found the correlation coefficient for each unqiue pair of these variables through Spearmann (underlying data does not have normal distribution)...
aim6789's user avatar
  • 77
0 votes
0 answers
77 views

Clarification of one sided vs two sided p value following permutation testing

I am unsure as to how to compute a two sided p value following permutation testing, following different examples online. For example, this post Two-sided permutation test vs. two one-sided, gets the ...
aim6789's user avatar
  • 77
1 vote
1 answer
429 views

What's the difference between a Permutation and a Perturbation?

I frequently come across the terms Permutation and Perturbation within the field of explainable AI. I understand that both terms refer to methods that make changes to a sample's features. However, I'm ...
Connor's user avatar
  • 635
0 votes
1 answer
43 views

Number of ways you sit next to your friend with 4 other people at a round table [closed]

This is a question I have after seeing Q1 of this question. There are a total of 6 people including you and your friend, and you guys are about to sit at a round table. The method of counting the ...
user21's user avatar
  • 231
1 vote
0 answers
68 views

Permutation and order statistic

Let $X_1,…,X_n$ be i.i.d. random variables. Are these two equalities correct? $P[X_{(2)}<x_2,…,X_{(n)}<x_n| X_{(1)}=x_1]=\\ =n!P[X_{2}<x_2,…,X_{n}<x_n| X_{1}=x_1]=\\ =n! P[X_{2}<x_2]…P[...
Enrico's user avatar
  • 211
1 vote
0 answers
73 views

Permutation Test for mean ratio

I am given three vectors of length 11, that represent blood levels of a hormone measured after placebo, old and new treatment. ...
Joshua's user avatar
  • 11
2 votes
1 answer
138 views

How do you use numPerms to get the total number of unique permutations for a PERMANOVA?

I am trying to calculate the number of unique permutations for a PERMANOVA using the R adonis2 function but I am getting stuck on defining my permutation scheme. As ...
planktonQ's user avatar
1 vote
0 answers
234 views

Advantage and disadvantage of Wilcoxon rank sum test compared to permutation test [closed]

What is the advantage and disadvantages of Wilcoxon rank sum test compared to permutation test? I want to know at least one each based on the shape of distribution of raw data.
JH LEE's user avatar
  • 11
0 votes
0 answers
169 views

Question about how to think of the binomial distribution with a combination vs a permutation

I know there are many questions on why use a combination formula over a permutation formula for the binomial distribution ( for example here), but looking through multiple of these, I still don't ...
Steve's user avatar
  • 681
1 vote
1 answer
60 views

if a feature appears as the most important among a variety of models, does that make this feature empirically important?

Lets say that I train a variety of different models - SVM, XGBoost, LogisticRegression, Random Forest, KNeighbors, etc. I then take the permutation importance of each model, and find that ...
NFeruch - FreePalestine's user avatar
0 votes
0 answers
45 views

Populating an even distribution of values across multiple axis?

I'm trying to design an experiment with: x number of people y number of tasks z number of ...
BeRT2me's user avatar
  • 101
0 votes
1 answer
286 views

How many ways can you arrange the digits: {1,2,2}, so that the resulting number would be even?

To quote the whole question accurately: Various 3 digit numbers can be formed by permitting the digits 122. All arrangements are equally likely. Given that any resulting number is even, in how many ...
Richard Marin's user avatar
1 vote
1 answer
257 views

Calculate a permutation-based p-value for a risk ratio

Summary How do you calculate a two-sided p-value for a risk ratio/relative risk (obtained from a GEE logistic regression via predicting risks with and without a treatment) based on a permutation test, ...
JupiterM104's user avatar
0 votes
0 answers
99 views

sampling distribution of a test statistic when doing permutation test

In a permutation test, we have a test statistic $T$ (for example t-test, f-test, etc.) that is applied to the original data to obtain an observed value $o_{obs}$ for the test statistic. Next, the data ...
userOnion's user avatar
0 votes
1 answer
23 views

How to order individuals within groups where group order must remain the same [closed]

I am attempting to get every ordered combination of individuals in groups while keeping the order of the groups consistent. For example, there are four individuals in group 1, two individuals in group ...
guest_7865's user avatar
4 votes
3 answers
270 views

What is the chance all choices are different?

Suppose everyone (7 people) chooses independently and randomly out of 7 choices. What are the odds that no two people have picked the same option? I feel like the answer is $5040/823543,$ but I am ...
Sean's user avatar
  • 43
2 votes
0 answers
227 views

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 ...
ap3's user avatar
  • 131
0 votes
1 answer
494 views

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 ...
Michael's user avatar
  • 13
0 votes
1 answer
102 views

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 ...
Peiran Yu's user avatar
  • 119
0 votes
2 answers
44 views

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 ...
Canada's user avatar
  • 5
0 votes
2 answers
199 views

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 ...
MaskedCucumber's user avatar
2 votes
1 answer
965 views

Post-hoc test of two-way permutation ANOVA

I have a 2x2 study design to test the interaction between two drugs, with a single variable outcome. The data are very much non-parametric and it seems that a good alternative to the traditional two-...
Tim's user avatar
  • 21
1 vote
0 answers
63 views

How to correctly apply a PERMANOVA to a half-crossed experimental design

I'm a biologist and conducted an experiment in which I took analytical samples of aphid infested plants and analyzed them using metabolomics. The plants were chosen based on their Genotype (...
Pienatt's user avatar
  • 21
2 votes
1 answer
74 views

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 $\theta$ ...
Capucine25's user avatar
1 vote
1 answer
34 views

How many ways to order such that one group comes first?

This question arose while playing a board game that uses cards. Imagine we have 11 cards total. 3 are red (R), 1 is blue (B), and 7 are yellow (Y). How many ways can we randomly order the 11 cards so ...
jdcrossval's user avatar
0 votes
0 answers
331 views

Schitt’s Creek David Ring Combination

So I’ve been trying to figure this one out. On Schitt’s Creek, David wears various combinations of rings. He has four rings and he can arrange them on his ten fingers in various ways - each ring is ...
thesadstork13's user avatar
3 votes
1 answer
367 views

Quantitative/statistical comparison of two orderings/permutations

There is a couple, say, Theresa and Robert. They assess their preferences on 5 books by ranking them from the most attractive to the least one. Theresa: [0,4,3,2,1]...
Karel Macek's user avatar
  • 2,856
3 votes
1 answer
40 views

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 ...
Isabella's user avatar
  • 133
0 votes
1 answer
51 views

Intuition behind permutations + probability

I'm new to stats so I'm struggling to grasp the intuition behind permutations + probability. Would anybody be able to help me with parts (b) and (c) of this question? Any help is greatly appreciated :)...
lkdlst's user avatar
  • 3
3 votes
1 answer
71 views

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 ...
robertspierre's user avatar
-2 votes
1 answer
43 views

Permutations - counting [closed]

Four girls bought each a swimsuit , and they decided to share them . How many days are needed so that each girl will wear each swimsuit once ?
Jawad Jassar's user avatar
0 votes
0 answers
14 views

One sample data with unusual structure, permutation test?

I have N sets, each of them consisting of 1000 integer values. Typically, more than 90 % of values within a set is zero, thus median is zero. The nonzero elements are positive integers. We take N ...
NeuroPanda's user avatar
0 votes
1 answer
437 views

One sample permutation test on skewed data

I have one sample of values, each of them is a z-score from mutually independent z-scored distributions. I aimed at testing that the mean value of the sample is larger than zero. Originally I wanted ...
NeuroPanda's user avatar
0 votes
0 answers
13 views

Distribution of a rate in a subsample after permutation of the total dataset

I need to estimate the distribution of a rate in a subsample after permutation of the total dataset. I was wondering whether it's sufficient to use the binomial distribution with the global rate ...
Bakaburg's user avatar
  • 2,929
-1 votes
1 answer
79 views

Evaluate clustering accuracy based on an adjacency/similarity/connection matrix

Description In the classification tasks, the classification accuracy is computed by accuracy=n_correct/n_total For example, if I have three samples, and the ...
Wubin's user avatar
  • 11
1 vote
0 answers
265 views

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/...
boomkin's user avatar
  • 855
5 votes
2 answers
2k views

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 ...
kubato's user avatar
  • 51
18 votes
3 answers
1k views

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 ...
GioMott's user avatar
  • 291