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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6 views

Bayesian data analysis with R

Lets say I have a big list of phone models I have bought through the years with several features listed as a "checkbox"-style: ...
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0answers
4 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 ...
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0answers
10 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 ...
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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 ...
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0answers
8 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
19 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
13 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 ...
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1answer
9 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 ...
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0answers
13 views

R variable lengths differ when using predict function to produce graphs

I'm trying to use the predict function, I've successfully used it once but since then it hasn't worked again and I can't figure out why. My aim is to produce a graph with a line through it showing ...
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0answers
9 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 ...
2
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2answers
26 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 ...
1
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1answer
21 views

Hierarchical cluster analysis with a similarity matrix

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 ...
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0answers
12 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
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1answer
51 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
12 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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0answers
12 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 ...
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0answers
12 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
17 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
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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.
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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
22 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 ...
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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: ...
0
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3answers
47 views

how to calculate R-squared in glm?

I came up with below for my glm analysis but I need to calculate R-squared to cite in the paper? anyone can help me with this please? summary(lrfit) Call: ...
0
votes
1answer
13 views

Multi-class logistic Generalized Additive Models [on hold]

I am looking for a package for three-class logit and probit GAM. I have searched and found out that ZeligGAM in R works for this but it seems that it is only applied to binary dependent variables. In ...
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0answers
24 views

Quantile of a conditional cumulative bivariate normal distribution and R Implementation

I would like to compute a quantile Z of a conditional cumulative bivariate normal distribution. I have two questions: 1) Do I formulate the problem correctly? 2) How would I compute this quantile Z ...
0
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1answer
14 views

recode function [on hold]

Two sections of an introductory statistics class took a quiz. The highest possible regular score was 20. Some students got one point of extra credit from a bonus question. A passing grade is 60% or ...
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2answers
47 views

Building a regression Tree with R FROM SCRATCH

I am trying to build a basic regression Tree in R FROM SCRATCH (I know of rpart, tree, RandomForest,etc.). But it is just something that I would want to code myself for my culture. In terms of ...
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0answers
18 views

extremely high Cook's D & dfbetas results from influence.ME

I fit a mixed effects logistic regression with the glmer function from the lme4 package to some data I have. Next, I've been using the influence.ME package to run some diagnostics (e.g. Cook's D and ...
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0answers
14 views

Appropriate cluster method for 7-point scale data of 58 variables and 635 observations

My research buddy and I are conducting cluster analysis on survey data using a 7-point relevance scale (1=Not relevant, 7=Extremely Relevant). We have 58 variables, arranged in 10 groups of ...
4
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1answer
42 views

Is the `weights=` option in lmer() doing what I want?

I want to predict PGA golfer performance. I'm wondering if I am correctly giving more weight to more recent results by using the weights= option in the lmer() ...
0
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0answers
10 views

How to calculate the effect size after Welch ANOVA?

I used oneway.test() because Levene's test indicated heterogenity of variance. Unfortunately, I don't know how to calculate the effect size now. Does anybody have ...
2
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3answers
69 views

How does the logit link handle binomial (1/0) data?

I have a data set that contains a continuous explanatory variable and a set of responses as binary success and failures. For example, ...
0
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2answers
45 views

Incorrectly rejecting a null hypothesis

What is the theoretical chance that we (incorrectly) reject the null hypothesis in the following case? ...
0
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0answers
4 views

Simultaneous and Pointwise Confidence Bands for GAMs

I am performing a penalized B-spline regression on a simple time series of count data in R using the mgcv package. When I calculate a pointwise confidence band from the standard error of the fit based ...
2
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0answers
64 views

Structuring Many-Factor Data for Linear Regression in R

I have a fairly large dataset of the following form, and I want to run a linear regression returning coefficients for each factor: ...
0
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1answer
29 views

Fisher Projection vs Linear Discriminant Analysis [on hold]

Basically, I am confused between Fisher and LDA. Looking for differences between the two. How is the Fischer projection computed in R?
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0answers
10 views

Comparing adjacency matrices

I have 25 weighted adjacency matrices which can be potentially translate into 25 networks. I want to see how ``similar'' are the resulting networks (in a graph theory sense). Is there a way to do ...
0
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0answers
14 views

sapply with function using multiple columns as input [migrated]

I have a data frame with let's say 2 columns and 4 rows (it's bigger... I am just making it simpler) like this: Value: 0.2, 0.3, 0.5, 0.8 R: 1, 0, 1, 0 I m trying to write a sapply line that given ...
0
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0answers
6 views

error R in Crossvalidation (fold-3) and RR-BLUP and compare GBLUP [on hold]

Crossvalidation three sets of genomic evaluation methods (fold-3) and two   RR-BLUP and compare GBLUP we run the following command in the program R; 1-Sincerely, with thanks, the other two that I need ...
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2answers
41 views

Word frequency in a vector [on hold]

I have a vector file with 1000 values. All the values were generated using Random function between 0-1. ...
2
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1answer
13 views

Is RMSEA an absolute or relative fit statistics test?

I've been studying Structural Equation Model and I have a doubt about RMSEA. In the book Principles and Practices of Structural Equation Modeling Kline treats RMSEA as an approximate fit index (p. ...
2
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2answers
49 views

Grad level books for survivability analysis applied to manufacturing

I am looking for a grad level book on survivability analysis applied to manufacturing such as assembly lines. Preferably in R. I am familiar with measure theory, probability theory and R.
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0answers
9 views

R stepAIC multiple datasets

I have three datasets of similar(ish) sizes (268, 271 and 262), and a model I am trying to develop for describing a response variable within the data. I'm trying to use the ...
0
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0answers
17 views

Choosing k in consensus cluster plus using cophenetic correlation coefficient

I am trying choose best k from the consensus clustering using the Cophenetic Correlation Coefficient (CCC). I tried as follows. The correlation coefficients values are poor, i.e., ...
1
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0answers
14 views

Multinomial response with repeated measures

I'm studying how sex influences habitat use. I'm looking for suggestions on how to analyze a repeated measure design with a multinomial response variable. I should note that the number of repeated ...
0
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0answers
11 views

Calculating optimal alpha, beta, and gamma for Holt-Winters in R [on hold]

Is there a way to calculate the alpha, beta, and gamma parameters in R for Holt-Winters? I tried using the one provided from the HoltWinters formula but it didn't give an accurate answer for ...
0
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0answers
14 views

How to identify a SEM with formative dependent variable (with R's lavaan package)?

I have a formative construct in a structural equation model (SEM) which I would like to estimate with the function sem in the ...
0
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0answers
20 views

“R” computing derivative of multivariate spline

I am trying to compute the derivative of a multivariate spline, in fact bi-variate I use a b-spline univariate to create a basis, for the first x1 and second variable x2, then I use the tensor product ...
0
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0answers
20 views

Computing hazard ratio between groups adjusting for other confounding variables

I have groups formed based on BMI; consider the standard Underweight, Normal, Overweight, etc. groupings for BMI as you might see for classification. I'd like to form a hazard ratio for comparing any ...
2
votes
1answer
39 views

logistic regression with an imbalanced data set, picking threshold cut point

This question relates to whether it is a good starting point for a cut point in binary classification with logistic regression to the use the mean of the binary response variable as the initial cut ...