Kappa as a Measure of Concordance in Categorical Sorting
Cohen's Unweighted Kappa
Kappa with Linear Weighting
Kappa with Quadratic Weighting
Frequencies and Proportions of Agreement

B
Total
1
2
3
A
1
44
5
1
50
2
7
20
3
30
3
9
5
6
20
 Total 
60
30
10
100
k = 3
N = 100
Kappa provides a measure of the degree to which two judges, A and B, concur in their respective sortings of N items into k mutually exclusive categories. A 'judge' in this context can be an individual human being, a set of individuals who sort the N items collectively, or some non-human agency, such as a computer program or diagnostic test, that performs a sorting on the basis of specified criteria. [Click here for an explanation of the conceptual and computational details of kappa.]
To begin, select the number of categories by clicking the appropriate button below; then enter your data into the appropriate cells of the data-entry matrix. After all data have been entered, click the «Calculate» button. To perform a new analysis, click the «Reset» button and start over. The analysis assumes that each entered value is an integer equal to or greater than zero.T
Note that measures of weighted kappa are meaningful only if the categories are ordinal and if the weightings ascribed to the categories faithfully reflect the reality of the situation. The weightings in this case are determined by the imputed relative distances between successive ordinal categories. By default, each of these distances is set at '1'. You are free to change any or all of these distances, though I recommend you do so only if you have good reason for it.


Select the number of categories: 
       
Number selected =
 



Basis for weighting: imputed relative
distances between ordinal categoriesT
 1~2 
 2~3 
 3~4 
 4~5 
 5~6 
 6~7 
 7~8 
  successive ordinal categories 







  imputed relative distances 


Data Entry
B
Totals
1
2
3
4
5
6
7
8
A
















































































Totals 









   


The designation "nc" appearing in any of the following
cells means "this quantity cannot be calculated." This
will typically occur only when your data entries in the
above table include a substantial proportion of zeros.


Unweighted Kappa
Observed
Kappa

Standard
Error

 .95 Confidence Interval 

Lower
Limit

Upper
Limit

Method 1



Method 2




maximum possible unweighted kappa, given
the observed marginal frequencies

observed as proportion of maximum possible

Kappa with Linear Weighting
Observed
Kappa

Standard
Error

 .95 Confidence Interval 
Lower
Limit

Upper
Limit






maximum possible linear-weighted kappa,
given the observed marginal frequencies

observed as proportion of maximum possible

Kappa with Quadratic Weighting
Observed
Kappa

Standard
Error

 .95 Confidence Interval 
Lower
Limit

Upper
Limit






maximum possible quadratic-weighted kappa,
given the observed marginal frequencies

observed as proportion of maximum possible

Frequencies of Agreement
  Category  
Maximum
Possible

Chance
Expected

Observed
 1 



2



3



4



5



6



7



8



Total



Proportions of Agreement
.95 CI
of Observed

  Category  
Maximum
Possible

Chance
Expected

Observed
Lower
Limit

Upper
Limit

 1 





2





3





4





5





6





7





8





Composite





Confidence intervals for proportions are calculated according
to the Wilson efficient-score method, corrected for continuity.


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