Work out author contribution share instantly with clear inputs, formula shown and shareable results.
Credit allocation schemes differ sharply. On a six-author paper an equal split gives 16.7% each, while harmonic weighting gives the first author 40.8% and the second 20.4%. Second position under harmonic credit is 1.22 times an equal share - which is why the scheme chosen materially affects bibliometric evaluation.
Harmonic credit
share = (1/position) / sum of (1/k) for k = 1 to n
Arithmetic credit
share = (n - position + 1) / (n(n+1)/2)
None universally. Harmonic weighting matches the convention that earlier positions did more work, but many fields list authors alphabetically or by seniority.
They describe contribution types rather than apportioning fractional credit, which is more informative but harder to aggregate into metrics.