Educational research ยท Evidence concept
Data quality and evidence
Why source, coverage, freshness, currency basis, and missing observations belong beside every portfolio research result.
How to read it
Evidence quality starts with the provider and date range, then continues through common observations, missing-data handling, price basis, and any assumptions applied before calculation.
Why it matters
A result can be mathematically consistent and still answer a narrower question than the label suggests if instruments have different histories, stale observations, or incompatible price bases.
Evidence boundary
Quality metadata cannot make incomplete history complete. It helps readers decide how much weight to place on a result and what should be rerun before comparison.
These pages explain historical and diagnostic evidence. They are not forecasts, guarantees, or personal financial advice.