Questions tagged [r]

Use this tag for any *on-topic* question that (a) involves R either as a critical part of the question or expected answer, & (b) is not *just* about how to use R.

19,583 questions
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Tangency portfolio in R

I am trying to solve for an efficient portfolio in R. How do I translate my constraints for a tangency point for 2 risky asset portfolio, and a given risk free rate to R solve.QP function? So ...
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I just installed the latest version of R. What packages should I obtain?

Duplicate thread: What R packages do you find most useful in your daily work? Are there any R packages that are just plain good to have, regardless of the type of work you are doing? If so, what are ...
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How to fit a negative binomial distribution in R while incorporating censoring

I need to fit $Y_{ij} \sim NegBin(m_{ij},k)$, i.e. a negative binomial distribution to count data. However, the data I have observed are censored - I know the value of $y_{ij}$, but it could be more ...
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Python as a statistics workbench

Lots of people use a main tool like Excel or another spreadsheet, SPSS, Stata, or R for their statistics needs. They might turn to some specific package for very special needs, but a lot of things can ...
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Recreating traditional null hypothesis testing with Bayesian methods

I am trying to recreate (in R) a frequentist hypothesis testing in Bayesian from, by calculating Bayes factors of the null (H0) and alternative (H1) models. The model is simply a simple linear ...
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Is it possible to directly read CSV columns as categorical data?

I need to analyze with R the data from a medical survey (with 100+ coded columns) that comes in a CSV. I will use rattle for some initial analysis but behind the scenes it's still R. If I read.csv() ...
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What do the residuals in a logistic regression mean?

In answering this question John Christie suggested that the fit of logistic regression models should be assessed by evaluating the residuals. I'm familiar with how to interpret residuals in OLS, they ...
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Mixed regression models and custom link functions in R?

It seems like the current revision of lmer does not allow for custom link functions. If one needs to fit a logistic linear mixed effect model with a custom link function what options are available ...
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How could I predict the results of a simple card game?

I want to predict the results of a simple card game, to judge on average, how long a game will last. My 'simple' game is; Cards are dealt from a randomised deck to n players (typically 2-4) Each ...
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Visualizing two scalar variables over time

What would be the best way to display changes in two scalar variables (x,y) over time (z), in one visualization? One idea that I had was to plot x and y both on the vertical axis, with z as the ...
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How can I obtain some of all possible combinations in R?

Sometimes I want to do an exact test by examining all possible combinations of the data to build an empirical distribution against which I can test my observed differences between means. To find the ...
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A non-parametric repeated-measures multi-way Anova in R?

The following question is one of those holy grails for me for some time now, I hope someone might be able to offer a good advice. I wish to perform a non-parametric repeated measures multiway anova ...
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How can one speed up this correlation calculation in R without multicore?

I have a colleague who calculates correlations in which one set of scores for a subject (e.g. 100 scores) is correlated with another set of scores for that same subject. The resulting correlation ...
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What code would you put before/after your R session? [closed]

R allows us to put code to run in the beginning/end of a session. What codes would you suggest putting there? I know of three interesting examples (although I don't have "how to do them" under my ...
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Why does AIC formula in R appear to use one extra parameter than expected?

I'll use an example so that you can reproduce the results ...
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R command for stcox in Stata

What is the equivalent command in R for the stcox command in Stata?
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References for survival analysis

I am looking for a good book/tutorial to learn about survival analysis. I am also interested in references on doing survival analysis in R.
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Column Means Significance Tests in R

New to the site. I am just getting started with R, and want to replicate a feature that is available in SPSS. Simply, I build a "Custom Table" in SPSS with a single categorical variable in the ...
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How can I get R to stop autocompleting my quotes/parens? [closed]

When I type a left paren or any quote in the R console, it automatically creates a matching one to the right of my cursor. I guess the idea is that I can just type the expression I want inside without ...
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R lrm model with no predictors

I am creating multiple logistic regression models using lrm from Harrell's Design package in R. One model I would like to make is the model with no predictors. For example, I want to predict a ...
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Any suggestions for making R code use multiple processors?

I have R-scripts for reading large amounts of csv data from different files and then perform machine learning tasks such as svm for classification. Are there any libraries for making use of multiple ...
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Is PCA followed by a rotation (such as varimax) still PCA?

I have tried to reproduce some research (using PCA) from SPSS in R. In my experience, principal() function from package psych ...
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How can one empirically demonstrate in R which cross-validation methods the AIC and BIC are equivalent to?

In a question elsewhere on this site, several answers mentioned that the AIC is equivalent to leave-one-out (LOO) cross-validation and that the BIC is equivalent to K-fold cross validation. Is there ...
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Post-hocs for within subjects tests?

What is the preferred method for for conducting post-hocs for within subjects tests? I've seen published work where Tukey's HSD is employed but a review of Keppel and Maxwell & Delaney suggests ...
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How does random forest generate the random forest

I am not an expert of random forest but I clearly understand that the key issue with random forest is the (random) tree generation. Can you explain me how the trees are generated? (i.e. What is the ...
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Why is the average of the highest value from 100 draws from a normal distribution different from the 98th percentile of the normal distribution?

Why is the average of the highest value from 100 draws from a normal distribution different from the 98% percentile of the normal distribution? It seems that by definition that they should be the ...
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Time series for count data, with counts < 20

I recently started working for a tuberculosis clinic. We meet periodically to discuss the number of TB cases we're currently treating, the number of tests administered, etc. I'd like to start ...
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Free resources for learning R

I'm interested in learning R on the cheap. What's the best free resource/book/tutorial for learning R?
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I had a plan of learning R in the near future. Reading another question I found out about Clojure. Now I don't know what to do. I think a big advantage of R for me is that some people in Economics ...
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Where can I find useful R tutorials with various implementations? [duplicate]

I'm using R and the manuals on the R site are really informative. However, I'd like to see some more examples and implementations with R which can help me develop my knowledge faster. Any suggestions?
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What R packages do you find most useful in your daily work?

Duplicate thread: I just installed the latest version of R. What packages should I obtain? What are the R packages you couldn't imagine your daily work with data? Please list both general and ...