Cohen's kappa is a measure of the degree to which 2 raters agree. There is also a test of inter-rater agreement based on kappa. Use [inter-rater] if you are interested in other aspects of IRA, but not this specific measure.

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What is the intuition behind the Kappa statistical value in classification

I understand the formula behind the Kappa statistic value and how to calculate the O and E value from a confusion matrix. My question is what is the intuition behind this measure? Why does it work so ...
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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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29 views

Comparison test of reapeated Cohen's kappa

Suppose two raters judged a set of stimuli. Then Cohen's kappa was calculated as measure of inter-rater agreement ($\kappa_{pre-training}$). Suppose now that after a training session, the same two ...
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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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Kappa (interrater agreement) alternative for count-based data which results in inflated agreement at lower counts?

I have a data set where four coders are rating 800 items on various attributes. This is achieved by reporting a count of the prevalence of each attribute, e.g. rater 1 thinks attribute A appears in ...
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21 views

What is the best way to quantify concordance of two tests?

I have two different medical diagnostic tests, both test the same condition (binary outcome). The condition in question is rather vaguely defined, so they don't always agree. What would be the best ...
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29 views

Is there such a thing as a multidimensional kappa test?

I am involved with designing a new diagnosis method for a routine clinical procedure. I want to compare the agreement between operators to the agreement between methods. Is there such a thing as a ...
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61 views

Is there an effect size for Kappa's?

I am staring a project on comparing standard ways of creating a classifier with some heuristic methods. The heuristic methods should result in a faster training for the classifier but should result in ...
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46 views

How to calculate this kind of kappa?

A colleague and I are trying to annotate an alignment task. We have two documents. The first document is the original copy and the other document is a modified version. The other annotator and I ...
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25 views

Observer agreement with Cohen's Kappa - is there a way to combine ratings to investigate if one rating impacts the other

I am a medical scientist doing observer agreement analysis on some very simple data using Cohen's Kappa. I have 2 observers. They score a bunch of scans on a 3 point scale for a pattern called ...
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190 views

Agreement statistics for confusion matrix with nominal categories

I have a decision support system that recommends Treatments (T1 to T8) to patients, where ...
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68 views

Calculating agreement between an ordinal and continuous scale

I'm having a bit of trouble wrapping my head around something. I have a data set which contains two columns that essentially attempt to measure the same thing, one on a 1-50 continuous scale and ...
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2k views

Kappa statistic in plain English?

I'm reading a data mining book and it mentioned the Kappa statistic as a mean for evaluating the predication performance of classifiers. However I just can't understand this. I also checked wikipedia ...
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85 views

Is this classifier random?

I trained a classifier and got the following stats on some test data: ...
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280 views

Sample size needed for Fleiss' Kappa?

A group of raters (about 20) will be watching a series of videos and will be classifying them into 4 categories. I will be running a Fleiss' kappa to measure the agreement. How does one compute for ...
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125 views

Inter-rater agreement with multiple raters

Compare inter-rater reliability between 8 human experts and a computer I am running a study where I use automated analysis to analyse an EEG signal (brain activity) and quantify certain properties ...
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169 views

Inter-rater reliability: Nominal data, but *multiple ratings per unit/subject*, different raters

I have a data set, with each variable taking multiple values on a nominal scale. Separate raters could rate a given unit using more than one value per variable. That is, there are multiple ratings per ...
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1answer
128 views

Limitations of Cohen's kappa for sparse data?

Are there any limitations for using Cohen's kappa with sparse data? I need inter-rater agreement between 2 raters for ~15 items, and the data in the contingency table is quite sparse (0 in some cells, ...
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1k views

ICC and Kappa totally disagree

Much has been written on the ICC and Kappa, but there seems to be disagreement on the best measures to consider. My purpose is to identify some measure which shows whether there was agreement between ...
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68 views

Is Fleiss's $\kappa$ as conservative as Cohen's $\kappa$?

I know Cohen's $\kappa$ for inter-rater reliability is often regarded as a conservative estimation--e.g., Strijbos & al. below, who say The higher the number of categories, the smaller the ...
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64 views

When should I prefer kappa over accuracy for binary classification problems?

I'm using the caret package in R that provides two kind of metrics for classification problems - accuracy and kappa. When should ...
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111 views

Validity of grand mean intra-rater Kappa or ICC

For 5 raters, I have calculated intra-rater Cohen's Kappa statistics for the test-retest nominal ratings, intra-rater Kendall's tau-b statistics for the test-retest ordinal ratings, and intra-rater ...
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300 views

Quadratic weighted kappa versus linear weighted kappa

When should I use quadratic weighted kappa or linear weighted kappa? I have two observers evaluating the classes of a number of objects. The classes are fail, pass1, pass2, and excellent (ordinal ...
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1answer
33 views

Macro and Micro Inter-Coder/Rater Agreement

I have a labeling task with 4 labels for which I'm using 2 coders/annotators/raters. This labeling effort leads to a confusion matrix like the one in ...
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339 views

Strange values of Cohen's kappa

I have two raters who agree on 93% on the cases (two options: yes or no). However, when calculating cohens kappa through crosstabs in spss I get really strange outcomes like -0.42 with a sig. of ...
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297 views

Quadratic weighted kappa strength of agreement

In the case of the kappa-value there are some attempts to qualify how good or bad the agreements are. For example Landis & Koch in the article The Measurement of Observer Agreement for Categorical ...
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666 views

How to calculate error matrices, K hat and var(K hat)?

I have a very simple data set consisting of three columns: Ground Truth Canopy Class, Method 1 Canopy Class and Method 2 Canopy Class. Each row in the columns represents the canopy class (i.e. 1 ...
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514 views

Inconsistency of findings between Kappa and ICC for IRR study

I used the following R script to calculate the Kappa and ICC for a measured done by two raters on 23 subjects: ...
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277 views

How should I interpret the Kappa Fleiss test?

I noticed that when I have tables which the values are only 0 and 1, I get a kappa of 1 when the table is completely full of one, and when I have a table of zeros I get NaN as result using the irr ...
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109 views

Is it statistically correct and safe to calculate Kappa 2 test means of combinations of 2 against the value of a Fleiss' Kappa?

For my problem I have a group of p participants and s subjects. I was suggested to calculate the Kappa Cohen Test on ...
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75 views

What is currently the more accepted Agreement Between Raters Statistics or most referenced paper?

I found a question that is related here, but it doesn't really goes on what I want to know. I found a couple of papers using Kappa Statistic from 2006, and 2010, but afterwards I found other authors ...
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238 views

Software to compute p-values and Cohen's kappa for 10 by 10 contingency table?

I have a 10 by 10 contingency table with most of my cells = 0, and my total cell count = 70. Is there a statistical package or online calculator which I can use to obtain p-values and Cohen's kappa?
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1answer
205 views

Is the power for a Kappa test the same as underlying z-test?

The Kappa ($\kappa$) test is a Z-test kind of test. If I am not very wrong, to compute the $\kappa$ test, we can just estimate the appropriate variance $\hat {var}(\hat\kappa)$ for the kappa statistic ...
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Computing Cohen's Kappa variance (and standard errors)

The Kappa ($\kappa$) statistic was introduced in 1960 by Cohen [1] to measure agreement between two raters. Its variance, however, had been a source of contradictions for quite a some time. My ...
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Adjusting kappa inter-rater agreement for prevalence

I am trying to calculate kappa scores for present/absent decisions made by two raters and I have heard that they can be adjusted for prevalence of the object of measurement. Can anyone advise on how ...
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133 views

Ordered category agreement

I have data on two processes, where the process assigns elements into ordered bins. I am interested in testing for agreement between the processes. What is the best way to do this (R code)? Here is ...
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1answer
301 views

Inter-rater reliability with many non-overlapping raters

I have a data set of 11,000+ distinct items, each of which was classified on a nominal scale by at least 3 different raters on Amazon's Mechanical Turk. 88 different raters provided judgments for ...
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2answers
2k views

Assessing and testing inter-rater agreement with kappa statistic on a set of binary and Likert items?

I am trying to calculate inter-rater reliability scores for 10 survey questions (on which there were 2 raters)--seven questions are binary (yes/no), and 3 are Likert-scale questions. Should ...
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Inter-rater reliability for ordinal or interval data

Which inter-rater reliability methods are most appropriate for ordinal or interval data? I believe that "Joint probability of agreement" or "Kappa" are designed for nominal data. Whilst "Pearson" and ...