The Intra-class Correlation Coefficient measures the degree to which a categorical variable accounts for variability in a continuous variable. It is often used to index the degree of clustering in a dataset.

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interrater reliability for proportional (not count) data

My experiment has the following form: a rater assesses a visual image and records a single value, p, which is his estimate of the proportion of that image composed of a single color. Thus, the data ...
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15 views

ICC for growth model

I have searched quite a bit for this answer. Is there an ICC for unconditional growth models. Not the unconditional means model, but a growth model. I suppose I mean to ask is there a way to describe ...
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16 views

Observer agreement in multilevel binary data

I have a set of participants indicating with drawn circles where they experience pain on a manikin of the human body. These drawings were then independently rated by two human raters: each of 29 body ...
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31 views

Panel data: Compare two different assessment methods

Just wondering if anyone has any inventive (but relatively simple) ideas about how to approach comparing panel data from two different assessment methods that collect the same variables. Basically, I ...
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23 views

Intraclass correlation and simulating data

I will apologize in advance for this somewhat messy problem. I am trying to take an ICC reported from a previously published manuscript and design a general simulation program. Let's say the ...
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1answer
113 views

Interpretation of variance in multilevel logistic regression

Please help me to interpret the findings of my model. The specifications of the model are: Dependent variable: treatment (1) or no-treatment (0). Independent variables: age, number of drugs used, ...
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44 views

$R^2$ for mixed models = ICC?

I will be referring here to Nakagawa and Schielzeth (2013). As those authors state, $R^2$ for OLS regression could be defined as follows: $$R^2 = \frac{\sum^n_{i=1}(\bar{y} - ...
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218 views

Acceptable values for the intraclass correlation coefficient (empty model)

I'm using xtmixed in Stata to test a Hierarchical Linear Model. My problem is that variance at level 2 is about 4% of the total variance. So most of the variance is ...
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12 views

Intraclass correlation with a sparse rater-subject matrix

I'm working on a problem pertaining to the reliability of faculty evaluations of students. My dataset contains ratings of ~160 students given by ~50 faculty members. Most students are rated by 2 ...
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36 views

Adding in L2 predictor in GLiMM fails even though ICC is high

I'm using SPSS GLiMM to run a repeated measures logistic regression model. Research Qn I'm interested to know if a MP is more likely to make a particular response (e.g., apology, challenge, denial) ...
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25 views

How do you aggregate individual scores to a team level using ICCs?

I'm pretty sure that at this point I have read every article and forum post that has to do with aggregating scores to a team level. I've learned how to do the some of the analyses, like R(wg) and ...
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32 views

type of ICC coefficient to use in my study for inter und intrarater-reliability

I am new to the subject and not sure, which ICC I have to use in order to analyse inter/intrarater-reliability of my measurements. A physician examined 649 healthy individuals with an ...
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7 views

Comparing TrueScore with the System Score

I have collected three human raters scores for an essay question(N=54). I am building Automated Scoring Algorithem. So I need to compare my machine score with the Human rater score. All are using 0-10 ...
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147 views

Multilevel logistic regression with a random slope(s)

I would like to specify a two-level logistic regression model with random intercept and random slope. Dependent variable: hospitalization (1) or no-hospitalization (0). Independent variables: age, ...
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120 views

Intraclass Correlation Coefficient in mixed model with random slopes

I have the following model m_plot fitted with lme4::lmer with crossed random effects for participants (...
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244 views

How to interpret glmer results (variance, correlation and ICC)

I'm a beginner in statistics and I have to run multilevel logistic regressions. I am confused with the results as they differ from logistic regression with just one level. I don't know how to ...
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31 views

ICC to assess independence of observations in a cluster randomized trial

How can I compute an ICC to assess independence of observation assumption using SPSS for ANOVA. The data on two DVs were collected from participants one time over 28 weeks in 28 clusters (so this is ...
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41 views

What are the tests to measure agreement between two methods of measurement when the unit of measurement is different between the two methods?

Bland-Altman plot measure the agreement between two different methods which measures the same variable. As far as I understand Bland-Altman can measure only if the two methods have the same unit of ...
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52 views

Intraclass Correlation Coefficient Question

I have two datasets in which I probably need to use the intraclass correlation coefficient, and I want to make sure I choose the right type. Dataset 1: I had 20 randomly selected human subjects rate ...
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1answer
57 views

Classification using correlation

Given two correlation matrix (each $p \times p$), where each belongs to a different group, is it possible to classify a new sample into one of the group (based on the correlation matrix only)? What ...
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77 views

How to test whether ICCs from different groups are significantly different?

I need to compare two generalizability (G) coefficients for data that are from two separate populations. G coefficients are a type of intraclass correlation coefficient (ICC). The literature on ...
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117 views

Should I use both paired t-test and intraclass correlation coefficient to examine the interrater reliability of an instrument?

As title, I am assessing the interrater reliability of a questionnaire (actually a Barthel Index (BI)) performed by four assessors (A,B,C,D) on about 25 test subjects. I plan to examine the IRR from ...
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21 views

Interpreting the relInterIntra {irr} results in R

I am using this for a reliability analysis test for quantitative values between two raters. I got my results using the "relInterIntra {irr}" package in R, but the reported values gave me several ...
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43 views

Non-normal data (ceiling effect) and intraclass correlation

I am wondering if there is any way of doing an intraclass correlation, two-way, mixed, with non-normal data (in this case a ceiling effect)? Alternatively, what the interpretation (if any) would be? ...
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68 views

'irr' R Package giving ICC values outside of 0 - 1

I ran a study looking at MEG (EEG with magnets) responses in the gamma-band (30-50Hz) range across multiple days. The following data is the timing of the initial response in that range (in seconds), ...
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25 views

How to analyse individual consistency from three non-normally distributed variables?

I would like to know if individuals were consistent across three different days. I measured the latency of individuals for a maximum of ten minutes. Many individuals had a latency of 0 and some ...
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27 views

Computing the Correlation with Skewed Repeated Measures Data

Suppose I have two variables (e.g., Blood Pressure and Cholesterol) and I want to investigate their association across time. Also suppose that each individual has been measured three times ...
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20 views

Reliability Measure for Unequal Subjects between Raters?

I am comparing two medical imaging analysis techniques, and I would like to assess the inter- and intra-rater reliability for using each method. I am planning the study design, and would like help ...
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742 views

Can ICC values be negative?

I am calculating the ICC as per the method of Shrout-Fleiss (1979), using the (3, 1) model in which the judges are fixed as are the targets. Some of my ICC values are negative. Is this to be ...
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42 views

Intraclass correlation coefficient: mean of raters, or better rater?

Suppose I have a set of stimulus, that was rated by three independent rater. I then estimated the Intraclass correlation coefficient, with a resulting value of 0.881. Let's consider a practical ...
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39 views

correlate/compare two scales measuring different constructs

I need to compare a multidimensional pain scale item response >3 pain is present and a scale measuring emotional suffering with classified levels of suffering (High, intermediate and low). Will ICC ...
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92 views

Likert scale inter rater agreement

What is the best inter rater agreement test for Likert scale type questions. As far I saw that cronbach alpha is for internal consistency, or it shows how good items are related to describe the main ...
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73 views

Correlated predictors in linear model: where does shared variance go?

I analyze a dataset consisting of responses to two conditions with a multiple regression analysis. I dummy code the two conditions to retrieve the contribution of each of them to the data. Up to here, ...
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89 views

Measure of accuracy or measure of agreement for continuous data with true values

I have two continuous variables. Variable $X$ represents the true values (basically it is atmospheric pressure measured via a barometer). Variable $Y$ represents a way to approximate the atmospheric ...
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97 views

Intraclass Correlation Coefficient Confusion

Many times in statistics we are using a statistic in different ways. I think Intraclass correlation coefficient is one of them... Intraclass Correlation Coefficient can be a A) measure of inter-rater ...
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Assessing test-retest reliability of a questionnaire [duplicate]

I am testing the test-reliability of a newly developed questionnaire over two time points. The study involves parents answering about their child over the two occasions. Would intraclass correlation ...
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1answer
34 views

Statistic to find out association between ordinal data

I have a 4x3 contigency table with ordinal data for a research finding in tuberculosis, I analysed cytology patterns and afb patterns; cytological pattern $A,B,C,D$ (independent variable) and afb ...
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57 views

What is a “subject” in ICC?

I have been working in R and have finally got some code working regarding intraclass correlation coefficients. In the output I get something called "subjects". I thought it was to do with the number ...
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121 views

Mean pairwise Pearson correlation

Consider a set of $M$ multidimensional observations $X=\{x_i\}_{i=1..M}$ for $x_i\in\mathbb{R}^N$, and define $c_{ij}$ to be the Pearson correlation coefficient between $x_i$ and $x_j$. Is there a ...
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40 views

Comparison between fat-matrix

I have two data sets obtained from two different kind of chemical analysis: GC-MS and IR. Both the chemical analysis were performed using the same samples. My aim is to know if there are some ...
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1answer
406 views

ICC in a linear mixed model - longnitudial data - why is this the correlation between time periods?

I'm confused by the description of the intraclass correlation (ICC) for a linear mixed model with longitudinal data from this material. A screen capture is shown below. What I'm confused about is ...
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1answer
233 views

Measuring intra-observer correlation

We're far from what you'd call expert statisticians, so we'd like to ask some help in an ongoing medical research. We have 60 subjects. A researcher took at least 3 times the measurements of 8 of ...
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764 views

How to compare repeatability (ICC) of different groups?

I have calculated the ICC values for two groups and would now like to compare the ICC values to determine if the groups differ in their repeatability. In the literature people have simply used t-tests ...
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368 views

Intra- and inter- observer error, and the intra-class correlation coefficient (ICC)

I have 3 observers, who each perform multiple observations in which they count a phenomenon. I'm trying to quantify both inter- and intra- observer error for this study. I'm new to this and am finding ...
2
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1answer
117 views

ICC - unclear comment from reviewer

I'm new here and not a statistician, so I apologize in advance and I sure hope someone can help! I'm working on a study where we have 10 locations $(5 \ intervention, 5 \ control)$. We have two ...
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232 views

Low intraclass correlation although between variance is very high in random effects model

I don't understand why a random effects model can give you a very low rho (intraclass correlation coefficient), if the between variance (between subjects) in your ...
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312 views

How to analyze intra-rater reliability with 31 raters who all rated 4 subjects twice

I'm trying to analyze the intra-rater reliability of an occupational therapy assessment. The assessment consists of 57 items, where some items are ratio data and some items are ordinal data. In my ...
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55 views

Averaging correlation matrices among subjects

Suppose I have N correlation coefficient matrices, containing the Pearson correlation coefficients of k different time series of ...
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33 views

Combining critic scores into single rating

I have a collection of scores from critics for various restaurants. Some restaurants are rated by multiple critics and some by only a single critic. Each critic rates restaurants using different ...
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128 views

Agreement of clustered data

I have the following situation: I have analyzed several data curves from a group of patients (16 curves per patient) with different analysis methods and want to test for the agreement of the methods. ...