# All Questions

140,691 questions
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### Is it possible to use the caret package in R with non-numerical data?

I was wondering if it is possible to use the caret package with non numerical data. I know, for example, if I want to use a simple linear regression lm I could have ...
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### Fit a robust regression line using an MM-estimator in R

Context. I'd like to fit a regression line to study to relation between some response variable $y$ and some continuous covariate $x$. Because of the presence of bad leverage points, I have opted for ...
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### Optimal data structure for 2-way repeated measures ANOVA

This must be a very basic question, but I'm trying to do a 2-way repeated measures ANOVA (in Statistica and/or SPSS), and was wondering: in what way to (re)structure my data so it is most flexible ...
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### How to compare two groups when there are many outcome variables?

Suppose we have two patient groups, healthy and ill patients, and we measure the chemical concentrations of multiple chemicals. Now we want to determine which chemical concentrations are different for ...
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### Why would concatenating feature vectors lead to better estimates?

I wish to estimate the state of a system from two separate and disparate observations. A simple approach that I have seen in some literature is to combine the feature vectors (observations) by simply ...
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### What are the sampling distributions of higher moments of the normal distribution?

Let $X_i$ be independent, normally distributed random variables, for $1\leq i\leq N$. What is the distribution of $Y_m=\frac1 N \sum_{i=1}^N X_i^m$? Every high school student knows part of the ...
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### p value correlation for random vectors in R

I want to calculate correlation coefficient between random vectors and use this for hypothesis testing. The code ...
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### What is the correlation of [1,2,3] and [1,5,7] to 8 decimal digits?

This stackoverflow post describes computing a Pearson correlation of [1,2,3] and [1,5,7] in several different ways in Python. The most straightforward implementation from the definition in Wikipedia ...