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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295 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 ...
2
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1answer
355 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, ...
2
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1answer
5k 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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0answers
88 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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0answers
119 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 ...
2
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0answers
170 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 ...
4
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1answer
546 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 ...
2
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1answer
59 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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2answers
468 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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2answers
588 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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1answer
1k 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 ...
3
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2answers
754 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: ...
2
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1answer
352 views

How should I interpret Fleiss' kappa when it equals NaN?

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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132 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 ...
2
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0answers
88 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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0answers
278 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?
4
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1answer
304 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 ...
37
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1answer
4k views

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 ...
3
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2answers
2k views

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 ...
4
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1answer
157 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 ...
6
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2answers
445 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 ...
4
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2answers
3k 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 ...
18
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2answers
17k views

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 ...