Clustering label agreement calculator

Calculate adjusted Rand index and unadjusted Rand agreement with your own figures.

Your numbers

Use the units shown. Results update as you change valid inputs.

Use adjusted Rand index and unadjusted Rand agreement to compare changes to your inputs. The method and limits below explain the scope.

Examples

Examples

Try the starting example

Records: unique sample ID, partition A label, partition B label
R1,A,X R2,A,X R3,B,Y R4,B,Y
Adjusted Rand index
1
Unadjusted Rand agreement
1
Total distinct sample pairs
6
Same-cluster pairs in both partitions
2
Same-cluster pair counts in A and B
2, 2

Try another scenario

Records: unique sample ID, partition A label, partition B label
R1,A,X R2,A,Y R3,B,Y R4,B,Y
Adjusted Rand index
0
Unadjusted Rand agreement
0.5
Total distinct sample pairs
6
Same-cluster pairs in both partitions
1
Same-cluster pair counts in A and B
2, 3
Calculation method

Calculation method

Adjusted Rand index

Exact integer chance-adjusted pair counts; degenerate identical pair relations return 1.

Unadjusted Rand agreement

Fraction of sample pairs whose same/different relation agrees.

Total distinct sample pairs

n(n−1)/2.

Same-cluster pairs in both partitions

Sum choose(cell count,2) over the partition contingency table.

Same-cluster pair counts in A and B

Sum choose(row count,2) and sum choose(column count,2).

Symbols and units
a
Records: unique sample ID, partition A label, partition B label

Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.

Assumptions & limits

Assumptions & limits

  • Compares two supplied hard partitions of exactly the same records, without fitting clusters or assessing their real-world meaning. Label names are arbitrary; degenerate identical pair relations, including one record, use agreement 1.
Are these inputs private?

These calculations run in your browser. A shared link contains the values you choose to share. Only questions submitted to the separate AI finder are sent to OpenAI.

Further reading

scikit-learn: adjusted_rand_score ↗

Background reading; this does not imply endorsement or independent review of SumFizz.

Share this page
Share this calculator

Leave unchecked to share the page without your entered values.