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`.

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1answer
10 views

Numerically Solve for Parameters Characterizing Lognormal RV that's Truncated from Above

I am trying to numerically solve for parameters characterizing a lognormal distribution truncated from above with first moment = mean, second moment = ...
0
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1answer
9 views

Beta distribution GLM with categorical independents and proportional response

My data is percentage disease data of different varieties of plants that had been inoculated with disease from several different sources. having conducted two-way ANOVA in SPSS (using the log10+1 of ...
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0answers
9 views

“Market” testing instead of A/B testing?

I believe in the last couple of years some respected research organization wrote a blog post about rigorous statistical testing of variables across markets (e.g., countries) when you can't do per-user ...
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1answer
25 views

Random Forest Overfitting R

I used a two-step cforest in my model. the accuracy of the train set is 87%, yet the accuracy of the test set is 57%. This indicates the model is severely overfitting. How to solve this problem? ...
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0answers
46 views

Mathematically,how are the critical t values calculated?

I am willing to write a program for calculating the critical t values,preferably in R. I am aware of the functions used for the same. But, I am interested in getting aware of the mathematical ...
1
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1answer
33 views

Material for teaching R to medical students [on hold]

I am planing to start teaching R to undergraduate medical students. I am looking for any material that can help in doing so. These students did not have any experience using R. Another question: Is ...
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0answers
14 views

Finding most relevant variables for components in PCA / MCA [on hold]

I am conducting PCA and MCA analyses in datasets with 150+ variables using Factominer in R. My main goal is to create 2-dimensional views of these datasets. After doing so, I would like to explain the ...
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1answer
33 views

Greek letters in R legend [on hold]

How can I add greek letters like "gamma" in the legend? My program: ...
0
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1answer
30 views

R function survfit(): give newdata reference values for factors with >2 levels?

The goal is to plot separate survival curves for each level of a categorical variable in R, using a coxph model including the variable and a second categorical variable with >2 levels. If the second ...
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0answers
15 views

Interpreting circular-linear regression coefficient

I'm trying to use the circular package in R to perform regression of a circular response variable and linear predictor, and I do not understand the coefficient ...
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0answers
7 views

Prediction using r mlogit: How to reproduce “Frequencies of alternatives” from model summary

I am trying to reproduce results in Train & Croissant's vignette "Kenneth Train’s exercises using the mlogit package for R." Specifically, Train illustrates multinomial-logistic regression using a ...
1
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1answer
23 views

Interpret Wilcoxon-Mann-Whitney Result in R [duplicate]

I am doing a Wilcoxon rank sum test (aka Wilcoxon-Mann-Whitney) with R. There are two variables "ScorePerView", that is metric and "HasCodeElement", that is binary. So the syntax is like that ...
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0answers
16 views

t.test applied in pairs to more than two samples in R

I have 44 samples where I only have its sample size, average and 1 standard deviation. I asked about the possibility of doing a t.test and some of you returned the answer: ...
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0answers
6 views

Estimation of scale parameter and shape parameter of using 'maxLik' package [on hold]

I want to test the closeness of my sample data with the Generalized Exponential (GE) distribution. For that, I am using ks test in R. In the documentation of ...
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0answers
29 views

Why do sample ACF/PACF suggest different TS models after box-cox transformation?

I use auto.arima function in R to fit a TS model to a annual data composed of electricity demand. The series is twiced difference to eliminate the trend in the data. After that the data is transformed ...
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2answers
23 views

How to calculate the probability of success of a Logistic Regression model with a single continuous predictor?

I have a logistic regression model below, predicting a dichotomous variable type from a single continuous predictor fatigue. Using the coefficients below I can obtain the increase in the odds of a ...
0
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1answer
15 views

Flag Random or Nonsensical Entries in a data set using R

This is a variation on my question Machine learning to catch fraud I have a data set with about 5 million rows The data set contains names and addresses of companies The name of the company is free ...
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0answers
17 views

Descriptive statistics in my native language in R [migrated]

Regardless of R! variables: Sys.setlocale("LC_MESSAGES", 'pl_PL.UTF-8') Sys.setenv(LANG = "pl_PL.UTF-8") when I use function such as summary, output is given in ...
0
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0answers
16 views

R for lme complicated study design

I have a data set where siblings (brothers and sisters) had the quantity of a specific bacteria measured at specific intervals since their birth (2 weeks, 1 month, 2 months, 6 months, 1 year). Because ...
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0answers
8 views

R - cor.ci results interpretation

I am doing some survey analysis for my dissertation, and am interested in studying possible correlations between four variables, based on Technology Acceptance Model.The survey is built on a ...
0
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0answers
8 views

How to check stability condition of VEC estimates in R?

I am estimating a VEC model and need to check the stability of its parameters. The vars package has a function to do this on an object of class varest generated by ...
1
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1answer
18 views

Different output for cox regression in R vs SPSS

During my analysis that I perform with a collaborator we get consistently different ouputs in cox regression between R and SPSS. Betas and p-values differ minutely, usually somewhere in the third or ...
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0answers
12 views
0
votes
1answer
13 views

Confidence intervals for Tobit model in package AER in R

I use a Tobit model to predict censored data. I use the AER package in R. A toy example looks as follows: ...
0
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0answers
12 views

How do I check whether my data fits exponential or lognormal or weibull using chi square and ks tests in R?

I'm a newbie to R language and I need to quickly find whether a set of data I have in a CSV file fits the three distributions Generalized exponential, log normal and Weibull. I need to test it using ...
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0answers
20 views

How do I use MatLab or R data model in an machine learning application [on hold]

I want to use matlab or R to create a prediction model, once this is complete how would I use that model in a an application?
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0answers
11 views

How to extract values for only one particular fixed factor from lmer object in R? [on hold]

I have following output for lmer object constructed using coxme package: ...
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0answers
10 views

Correlation analysis and Clustering in R - Some suggestions [on hold]

I have a biological data, comprising of intensity values associated to 24 masses. Each mass file has 10,000 intensity values corresponding to 10,000 coordinates. So, the data matrix in R would look ...
-2
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0answers
13 views

Bayesian data analysis with R [on hold]

Lets say I have a big list of phone models I have bought through the years with several features listed as a "checkbox"-style: ...
0
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1answer
20 views

MLE of Gamma when only given observations [on hold]

i've been given 10 observations of X, where X is a random variable. the observations are 141 16 46 40 351 259 317 1511 107 567 and now given they are gamma distributed, how do you find the MLE using ...
1
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1answer
18 views

Bland & Altman plot for repeated measures using one measuring device

I am examining the reliability of a measuring device by measuring a force generated på test persons 7 days apart using R. In order to assess this properly I want to make a Bland & Altman plot ...
1
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0answers
45 views

How to detect different social groups in a small questionnaire dataset?

I work with a very small questionnaire dataset, in which perception of 10 respondents to the size of, say, an unseen population is quantified: The population is divided into eight sub-populations, and ...
0
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0answers
18 views

R ggplot2: overlaying multiple geom_ribbon objects in a single plot using a nested loop [migrated]

I have five line plots from which I'd like to output a shaded area that represents the region between their plotted upper and lower regions. I'm creating an R script (see below) as I have multiple ...
0
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0answers
9 views

How can I determine a transition point in a curve?

I have plotted a bar graph and knowing that the transition in the curve takes place around values 21 to 25 , I want to find such point in general. ...
0
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1answer
24 views

Comparing Height of Web Page against Scroll %

I have a collection of 108 data points in the following format: page height | % of users who scrolled upto 25% of page | 50% | 75% | 100% (full page) I'm trying ...
1
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0answers
40 views

Reporting the Actual Formula/Equation of an LME model (with factors) used in R?

I have a dataset that has measurements of resource consumption in buildings for a number of years. I am interested in the differences in resource consumption of buildings in my study area between ...
0
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1answer
14 views

Can adding uniform sampling weights change p-values?

I am doing an analysis of Average Marginal Component Effects (AMCEs) of a conjoint experiment in R. The package I use, cjoint 2.0 (see amce function), allows to add sampling weights (I want to compare ...
0
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0answers
11 views

Displaying data characteristics after multiple imputation

I have original data which I run a few commands on to get a feel for the data. For example, I have men and women, and in each group, I have the percent in each cancer type (eg brain, lung). In the ...
3
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2answers
49 views

Understanding the direction & strength of a correlation, & causal status, from a chi-squared test

I am analyzing Stack Overflow Posts. So I have a database with 1000000 questions, their current score (upvote or downvote) and a flag, that there is a source code part in the question (or not). So I ...
0
votes
1answer
28 views

Hierarchical cluster analysis with a similarity matrix [on hold]

I am trying to analyse the results from a card sorting study i did, but all i have is raw data. I have the similarity matrix for 53 cards, but I am trying to figure out how to do a hierarchical ...
0
votes
0answers
14 views

Separation problem in GLM

So I think I have a separation problem in my logistic regression model. The response variable (that only takes 0 or 1 values) takes 99.2% of its cases as 0 and only 0.8% as 1. This is the ROC curve ...
1
vote
1answer
57 views

Why is my density plot just a line on the bottom?

Basically, I'm just trying to plot a curve over my histogram for the weight of a few students. lines(density(weight), lwd = 2, col = "red") However, what I get ...
1
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1answer
13 views

Model matrix for linear model with multiple contrasts

I don't fully understand the concept of a model.matrix. Assume I have the following experimental design: ...
0
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1answer
24 views

aggregate all data by Date and ID

I have a dataset with 20 different columns and i want to aggregate all of the columns by the first two columns (Date and ID). Is there a way to say aggregate all instead of typing the names of the ...
0
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0answers
14 views

Understanding my serial mediation from R and creating a serial mediation model

I am having trouble understanding my serial mediation results from R. I think that my results are significant, but I'm not sure how to create a model using my results. Can R create the model on its ...
1
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0answers
18 views

PLS with more variables than data points

Does it make sense to run partial least squares (PLS) on a data set that has many more columns (variables) than it has rows (data points)? I am using plsr in R. I ...
-1
votes
1answer
28 views

Gaussian processes ordinal regression in R [on hold]

Is there any ordinal regression using gaussian processes implemented in R? I made a research in the Internet, but I didn't find anything.
0
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0answers
12 views

Comparing odds ratios - conditional or unconditional MLE

When comparing log(OR) from two contingency tables using Z-test should I use conditional maximum likelihood estimate of odds ratios (as given by fisher.test in R) or simple unconditional?
1
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1answer
26 views

Time-dependent variable in survival analysis using R

I am conducting a retrospective study where I have a cohort of cases who underwent the same surgical procedure. The primary outcome of the study is the recurrence incidence rate during a follow up ...
0
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0answers
19 views

Comparing the estimated coefficient in Logit versus Mix Logit, regarding the scale parameter

My question is how can I compare the estimated parameters for a logit model with a mixed logit model? I am using mlogitpackage in R and my code is as follows: ...