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The distribution of K until the n-th occurance of a poisson process takes place

Let's take the following scenario: Customers arrive at a shopping mall according to a Poisson process with a rate of λ per minute. The mall has a door that closes ...
Sandra Sukarieh's user avatar
0 votes
0 answers
4 views

Repeated measures microbiome data with baseline measurement: comparison of two treatments

I am interested in any advice I can get on different ways I might analyze multivariate ecological community (fecal sample microbiome) data that come from a "before after control impact" ...
qdread's user avatar
  • 285
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0 answers
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Is collinearity in Random forest an issue? how to solve it? [duplicate]

The question is whether highly correlated variables pose a problem in random forests. How to solve it? For instance, if we have a random forest model with two variables representing salaries and ...
yav dat's user avatar
0 votes
0 answers
5 views

Does replacing binned variables with Weight of Evidence values introduce data leakage?

In my company I've been noticing some binary classification modeling code that replaces bins of a continuous variable with the corresponding Weight of Evidence (WoE) of the given bin. As far as I ...
jglad's user avatar
  • 33
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0 answers
15 views

Obtaining P value in LASSO regularized linear regression showing that the model is generalizable

I have a problem. I am a biologist working in machine learning. Recently I am dealing with LASSO regularized linear regression. Very nice RMSE, MSE, R^2 values under all kinds of cross-validation. But ...
Mátyás Bukva's user avatar
2 votes
0 answers
15 views

Timeseries problem with law of large numbers

Let us have an AR(1) model with individual efect $$y_t = \alpha + \theta y_{t-1} + \varepsilon_t$$ with $|\theta|<1$ for stacionarity and $\varepsilon_i$ i.i.d. from distribution with mean $0$ and ...
David Paleček's user avatar
0 votes
0 answers
21 views

When the expected value of the gradient of function is equal to the expected value of the function multiplied by the gradient itself?

I'm having doubts on the conditions of an equality. Considering $f(X,w): \mathbb{R}^n \xrightarrow{} \mathbb{R}^n$ a function of n-variate random variable $X$ with an unknown distribution $p(x)$ and $...
GM_'s user avatar
  • 1
1 vote
0 answers
16 views

(Bayesian) Quadrature when the density can be factorised with respect to a directed graph

I am very new to (Bayesian) quadrature and am trying to understand if or how we can use additional information to approximate our definite integral. Specifically, I am interested in the expected value....
Astrid's user avatar
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0 votes
0 answers
23 views

Calculating a (combined) variance of two samples with unequal variances

Before I state my question, I would like to point out that I do not have a mathematics/statistics background, so please excuse my lack of rigor in the terminology I use. I have two datasets of unequal ...
Dan's user avatar
  • 1
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0 answers
15 views

BIvariate Normal and Conditional Expectation

I am working on a problem where I must show that the conditional distribution of Y given X follows the distribution with mean and variance shown below. In the previous question, we were given that X ...
Harry Lofi's user avatar
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0 answers
16 views

Scaling data to a sample that is neither training nor validation. Is this data leakage?

TL;DR: Data being scaled to a sample that is neither training nor validation. Is this data leakage? Hi, I have a data set from samples that are distributed on a plate. Precisely, there are 96 wells ...
Luiz Gustavo's user avatar
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0 answers
15 views

Reasonable hypothesis testing from confidence interval oracles

Assume that we have two scalar quantities $X$ and $Y$, and a confidence interval oracle $CI$ for each of them, so that $CI_X(\alpha)$ and $CI_Y(\alpha)$ will produce level-$\alpha$ confidence ...
Marc Vaisband's user avatar
1 vote
0 answers
38 views

What is the correct way to perform one sample paired wilcoxon test?

for simplicity, let's say I have a dataframe called df, with two variables - weight_0 and weight_1. weight_0 describes the weight of participants before intervention, and weight_1 describes the weight ...
Luis_12345's user avatar
0 votes
0 answers
14 views

Determines the probability that a specific order of repair will be chosen

Consider the statement In an appliance repair shop, the following are found $10$ televisions for repair, of which $3$ are of brand $A$, $3$ of brand $B$ and $4$ of brand $C$. The order in which the ...
Wrloord's user avatar
  • 135
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0 answers
38 views

Causal relationships with a specific correlation structure

Can three distinct causal relationships (labeled A, B, and C) be constructed to yield a common targeted correlation matrix (e.g., $r_1=0.6,~r_2=0.5,~r_3=0.4$) as depicted in the figure below? If ...
bluepole's user avatar
  • 2,699
1 vote
0 answers
11 views

Do operator on a 2 node system

If my causal structure consists of $y$ influencing $x$, my understanding is that $p(x|do(y=1))=p(x|y=1)$. But what is wrong with the following argument? $$p(x|do(y=1))=p(x|y=1)=\frac{p(x,y=1)}{p(y=1)}=...
theQman's user avatar
  • 677
3 votes
2 answers
48 views

Why is it that scaling my density plot from counts changes the y-axis so much?

When I make a histogram I get the actual distribution of my samples, with the appropriate counts, but when I try making a density plot the scales go up to 800, and when I try using ...
maglorismyspiritanimal's user avatar
2 votes
0 answers
24 views

Difference in SAS PROC MIXED between DF when using type VC vs FA0(1) for one random effect model

I don't understand why the degrees of freedom (DF) are different between TYPE=VC and ...
Davor Josipovic's user avatar
0 votes
0 answers
10 views

Tuning the learning rate parameter in GBDT models

I've always been taught that decreasing the learning rate parameter in gbdt models such as XGBoost, LightGBM and Catboost will improve the out-of-sample performance, assuming the number of iterations ...
Casper's user avatar
  • 1
0 votes
0 answers
15 views

Problem in PCA plot analysis

I have generated these two PCA plots on Galaxy using two different GEO datasets, as a part of RNA-Seq analysis. In both, each group has several clusters. Also in the Obese vs Control dataset, the PC1 ...
Sanjukta Ghosh's user avatar
0 votes
0 answers
12 views

Python/R Implementation of bandwidth selection in univariate KDE [closed]

I am looking for implementation of various univariate bandwidth selectors including rule-of-thumb, plug-in and cross-validation to do a small simulation study. As far as I am aware, there is no r or ...
abalone's user avatar
0 votes
0 answers
11 views

change of chi2 with Monte Carlo

I am reaching out to open this topic in order to clarify a point regarding chi-square and the influence of Monte Carlo on it. For purely informative purposes, I have decided to generate random data ...
Bastian's user avatar
0 votes
0 answers
11 views

Model with time as predictor but some rows have large time span

I want to model a linguistic feature (number of a certain word at the beginning of the sentence) through centuries. I am familiar with logistic regressions, Poisson regressions and GAMM to model such ...
Giuseppe Magistro's user avatar
-2 votes
0 answers
13 views

how to pass data through link tag without using react-router-dom? [closed]

return {/* Categories */} Categories <Link href={'/admin/categories/create'}>Create
Vedant Khamar's user avatar
0 votes
0 answers
18 views

How to quantitatively measure change in frequency tables over time? [closed]

I have a frequency table created daily for certain data points. There are 3 cases for data points: Some data points may go away from T-1 to T. Some data points will remain from T-1 to T but their ...
nisban20's user avatar
0 votes
0 answers
25 views

Gaussian process with empty measurements [closed]

I'm wondering if I can use Gaussian Processes to find the functions with not only some existing measurements but also observed areas of no function values. Gaussian process is a distribution of the ...
siadajpan's user avatar
0 votes
0 answers
12 views

Sample size for probable/severity errors over 10,000 tasks

I have been given a task of finding the required sample-size when testing various pieces of software. After some googling and a bit of a chat with Chat-GPT I think I have a formula but would like a ...
Darren Bartrup-Cook's user avatar
0 votes
0 answers
15 views

Running Bootstrapping on GAMLSS [closed]

I'm trying to evaluate my model's performance using bootstrapping and this is the function I'm using: ...
9id9's user avatar
  • 1
0 votes
0 answers
11 views

NA results after pooling estimates and coeff of mixed effects cox model from MICE imputation dataset

I need your help with my problem. So, after step of imputation missing data through MICE method, I got multiple imputed dataset. Then, I pooled the estimates and coefficients with mixed effect cox ...
Hoang-Giang Pham's user avatar
2 votes
1 answer
35 views

Application of robust Poisson regression

I am applying a Poisson regression with robust standard errors to model a binary response variables. I was wondering what are the assumptions underlying this type of regression? Does robust Poisson ...
zhiheng yi's user avatar
0 votes
0 answers
6 views

Best statistical model for pre post measurement (RCT) with two groups (treatment and control) and baseline differences?

I know there are several different models to chose from. I would like to know which one is the most appropriate (advanced) and if I should include baseline differences concerning the dependent ...
Verena M.'s user avatar
0 votes
0 answers
35 views

How does simulation help check if model assumptions are met?

I am trying to understand how simulation can be used to check if (regression) model assumptions are met. For example here is a linear regression model: $$y = \beta_0 + \beta_1x + \epsilon$$ I ...
ionojoseph's user avatar
2 votes
1 answer
100 views

How to determine the best fitted model by AIC between lm(y~x),lm(log(y)~x), drc(y~x) in R

...
user408308's user avatar
1 vote
1 answer
30 views

What is the intuition behind the single-pass algorithm (Welford's method) for the corrected sum of squares?

The corrected sum of squares is the sum of squares of the deviations of a set of values about its mean. $$ S = \sum_{i=1}^k\space\space(x_i - \bar x)^2 $$ We can calculate the mean in a streaming ...
Foobar's user avatar
  • 327
0 votes
0 answers
34 views

what's the best loss/evaluation metrics for regression if the target is normal distributed and have a 0 mean [closed]

there is a random variable ~ N(0,σ2),you are given a bunch of features associated with the random variable and you want to predict the value of the random variable with a regressor, what is the good ...
Wuuu's user avatar
  • 1
0 votes
1 answer
31 views

Multiple linear regression slopes inconsistent with graph - why?

I am doing a multiple linear regression, with 3 categorical predictor variables (Flow, Drug, Pesticide) each with two levels (0 vs. 1). The response variable is the abundance of invertebrates. I have ...
blue_earth's user avatar
0 votes
0 answers
18 views

Closed form solution to lasso and ridge regression

I'm trying to figure out how to find the closed form solution for ridge and lasso regression. I'm confused on how you go about isolating $\beta_i$ for both. Ridge: $\hat{\beta}^{Ridge}(\lambda) = \...
cardinalcat27's user avatar
0 votes
0 answers
10 views

Weight of Evidence for dataset with weights [closed]

I want to calculate weight of evidence for a dataset with weights. I want do it for both continuous and categorical data. I understand this formula -> WOE = ln(% of non-events / % of events) but I ...
Shivaranjani C's user avatar
0 votes
0 answers
18 views

Compare 2 systems using pairwise preferences

I have systems A and B. I sample N inputs $X_i (0 \leq i<N)$ and run them through each system, getting outputs $A_i$ and $B_i$ for every $i$. I also have a random vector $Flips_i \backsim Bernoulli(...
Alexandre's user avatar
  • 338
0 votes
0 answers
27 views

AR(2) model proving stationarity [closed]

Given equation $$X_t = 1.3X_{t-1} - 0.4X_{t-2} + \epsilon_t + 2.5,$$ have to prove it is stationary. transform: $$X_t(1 - 1.3\phi + 0.4\phi^2) = 2.5 + \epsilon_t$$ take equal to 0 $$1 - 1.3Z + 0.4Z^2 =...
undergradstdt's user avatar
0 votes
0 answers
25 views

How to label fraud vs no fraud [closed]

I am trying to create labels for sellers as fraud or no fraud . I have an e-commerce site. I have some positive fraud samples labeled manually.I have a model that predicts whether the claim is fraud. ...
Mnag's user avatar
  • 1
3 votes
2 answers
286 views

How to evaluate the impact of an intervention with no control group?

I launched a campaign where I give certain users 20% off. This was not launched as A/B test. I’m trying to figure out how to evaluate the incremental impact + ROI of the intervention given that it was ...
ibarbo's user avatar
  • 65
0 votes
1 answer
24 views

F-distibution only depends on degrees of freedom

I am reading ISLP Chapter 3.2 on multiple linear regressions. They define the F-statistic as $S_1$, the variance of sample 1 from population 1, divided by $S_2$, the variance of sample 2 from ...
amineh's user avatar
  • 43
0 votes
0 answers
21 views

My WGAN-GP isn't capturing bi-modal distributed underlying data

I am training a WGAN to generate a vector of 6 data points (6 dimensional output). I plotted a correlation matrix of my dataset to see the underlying distribution of the 6 data points, and the ...
ShrHon's user avatar
  • 1
0 votes
0 answers
23 views

Can I use month variables to capture linear increases and seasonal effects in the same model?

I have count data (numbers of articles published) that I want to model as a function of time and location. I suspect there's an increasing linear effect with time but also a seasonal boost in the ...
adkane's user avatar
  • 909
0 votes
0 answers
18 views

How can I compute a counterfactual query for discrete binary variables?

In computing counterfactual queries for structural causal models (SCMs), J. Pearl says to go through 3 steps. Abduction Action Prediction In his book, Causal Inference in Statistics, he shows how to ...
Jane Wayne's user avatar
  • 1,389
0 votes
0 answers
43 views

Two-proportion hypothesis test with variances unknown

"A group of test subjects are split into two groups. 1000 people are given a vaccine, and 15 of them get the disease. 800 people are given a placebo, and 60 of them get the disease. Test the ...
Forklift17's user avatar
0 votes
0 answers
36 views

Non-parametric statistical test to compare a continuous and dichotomous variable in the same group

I want to compare between the level of Th17 cells in the blood of a group patients with Sarcoidosis, and whether or not it is correlated with them having fibrosis. So, a continuous variable and a ...
Alpha's user avatar
  • 1
0 votes
1 answer
44 views

Fisher's exact test when a category has a 0

I've been doing the univariate analysis for a retrospective cohorts study. In this variable in particular, none of the no-cured patients had a growth of grampositive bacteria in their culture. Since ...
user406570's user avatar
0 votes
0 answers
17 views

Interpreting Multidimensional Scaling (MDS) Plot: Rotation and Axis Orientation

First post here, so let me know if I'm missing things. I'm working with a multidimensional scaling (MDS) plot generated in MATLAB using cmdscale(1-(corr(Betas))). Based on prior experiments, I suspect ...
McKinney Pitts's user avatar

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