Demand evidence
Missing data is not zero demand.
When a demand signal is unavailable, the honest conclusion is usually “unknown”—not “none.” That distinction prevents a research gap from becoming a false fact.
Three different states
A measured zero means a defined method observed no qualifying events during a stated period. Missing data means the method could not observe or retrieve the signal. Insufficient data means some observations exist, but they are too sparse, stale, or narrow to support a stable conclusion. These states require different language and should not share the same numeric default.
For example, an interface may show no sold-history field because the source does not provide it. Recording zero sales would assert something that was never measured. The correct record describes the unavailable field, its source limitation, and any alternative evidence that might be considered separately.
Use a question-specific evidence plan
Before collecting observations, define what “demand” means for the question. Search interest, completed transactions, review growth, active listing turnover, and seasonal attention can each reflect different behavior. None is a universal substitute for another. Specify the time window, marketplace, product interpretation, and minimum coverage needed.
Next, label every signal as observed, estimated, unavailable, or not applicable. Preserve the observation time. If a signal is indirect, say what assumption connects it to the demand question. This makes the analysis reproducible and exposes where reasonable people may disagree.
A cautious fallback
When direct evidence is missing, researchers can describe visible supply, price movement, or listing persistence without converting those facts into sales. They can also defer the conclusion and identify the next verification step. A deferred conclusion is more useful than a precise-looking number without provenance.
What readers should take away
Good demand research is explicit about coverage. It does not reward missing fields with optimistic assumptions or punish them with invented zeros. State what was observed, keep unknowns visible, and make the conclusion no stronger than the evidence.