What’s a “seed weighting bias”?

Seed weighting bias occurs when your test seed distribution does not match your real audience distribution.

If 60% of your audience uses Gmail but only 30% of your seeds are Gmail, your aggregate placement results will underweight Gmail's influence on actual outcomes.

The reverse also applies. Overweighting a provider inflates its impact on your reported metrics.

To minimize bias, weight seed results according to your actual audience provider distribution.

If most of your trade goes to one port, focus your scouts accordingly. Reports from minor ports should not dominate your decisions.