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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0answers
15 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
4 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
7 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
14 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
11 views
0
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1answer
10 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: ...
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0answers
9 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
18 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
10 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
9 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 ...
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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
18 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
vote
1answer
17 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
26 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 ...
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
votes
1answer
23 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
19 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
votes
1answer
13 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
10 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
32 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
26 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 ...
0
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0answers
13 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
55 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
votes
1answer
22 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
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
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
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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.
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
24 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: ...
0
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3answers
53 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
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1answer
14 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 ...
0
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0answers
29 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
votes
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 ...
0
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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 ...
1
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0answers
20 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 ...
0
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0answers
16 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
votes
1answer
50 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
73 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
votes
2answers
47 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
5 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
66 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
votes
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?
1
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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
votes
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
votes
0answers
9 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 ...
0
votes
2answers
42 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. ...