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218,409 questions
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Similar PCA but I want every element of the first eigenvector to be positive / non-negative matrix factorization?
I am familiar with the PCA algorithm for dimension reduction. But I would like every element of the first principle component to have the positive sign. So when I try to use my principal component, it'...
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Standard error for total population ratio estimate bigger than the estimate of the population total itself
I have a sample of $n=100$ counties and I'd like to estimate a total number of veterans in a country (U.S.A.) of 3414 counties. To do that I use ratio estimate. The sample is drawn eith simple random ...
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Correct implementation of binary relevance
I have questions regarding Binary Relevance implementation.
How to treat multi-label problem with empty class? (I have instance that cannot have any label). Should I introduce new label "NoLabel" in ...
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Reproducing complex SAS `PROC MIXED` specification in R `nlme::lme()` with random effects and correlation structure
TL;DR I'm struggling to specify a PROC MIXED SAS model in R using nlme:::lme.
What I'm trying to do
I am trying to reproduce the ...
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Is it justified to include non-significant predictors in a model if it decreases the fit criterion (AIC)?
During analysis of a high dimensional dataset (92 cases, 400+ variables) with the goal of statistical inference, I first used a bootstrapped LASSO (bolasso) to select predictors, and then did an OLS/...
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Definition of the random-effect model
I am studying the random-effects model as a preparation for a meta-analysis. Unfortunately I am confused because there seem to be two inequivalent descriptions of the model in the literature:
In the ...
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Vector Jacobian product in automatic differentiation
My question is related to this post Higher Order of Vectorization in Backpropagation in Neural Network @shimao
I don't really get the following claim (I know how the chain rule works and what is the ...
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ARIMA model for vehicle-speed prediction
I am learning on how to predict with ARIMA models. To get some knowledge I read trough some online tutorials for R and ARIMA models.
Now I wanted to try this by myself with a problem I am currently ...
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Is it statistically valid to use windowed KDE-normalized patches for Jensen-Shannon Divergence comparison?
I'm working with a spatially distributed dataset where I first estimate the global empirical distribution using Kernel Density Estimation (KDE). I then divide the data into smaller spatial patches (...
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Interrater reliability: calculation when not all raters rate all cases?
I have 15 raters who rated 70 cases (Y or N). Each case was rated by 5-8 raters. Raters rated between 5 and 70 cases.
My goal is to (#1) establish a measure of interrater reliability and, if possible, ...
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Calculate correlation between time of day and number of created cases (call center)
I have a data set showing all incoming call during a month and the cases created by the call center agents. The cases are related to a specific call.
My hypothesis is that the agents create less ...
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Difference between ARX vs ADL
In this article they describe the ADL as a regression of y with itself and an explanatory variable. What is the difference between this and the ARX model?
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GAMMs in R: How to interpret global term when concurvity with group-level smoother is present?
I've fixed my model and incorporated all the terms I believe have an effect on my response (abundance of a single species), but I'm stuck on how to interpret the long-term trend plot, ...
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How to interpret Isolation Forest results on variations of train/test sets?
I have a labelled dataset, originally intended for classification or clustering tasks, whose minority class is at 10%. I am investigating whether this problem can be tackled with anomaly detection ...
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Custom contrasts involving interaction terms using emmeans
I'm trying to setup a custom contrast using emmeans but am a bit unsure on how to do so properly.
I have two factors, let's call them A and B, with three levels each.
I want to test the following ...
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