Two kinds of numbers appear on trading screens and they are easy to confuse. One says what is. The other says what someone expects. They are produced differently, they fail differently, and they deserve different amounts of trust.
What a measurement is
A measurement reads the present or the past. Open interest on a contract right now. The spread on a quote. The distance between a perp’s price and its price at the last cash close. Each can be checked by anyone with access to the same source at the same moment.
A measurement can still be wrong. The source may be stale, the instrument may be thin, the arithmetic may have a bug. Those are errors of instrument, and they can be found and fixed. Measured, retrieved or unknown describes how a reading can carry its own provenance.
What a prediction is
A prediction is a statement about a time that has not happened. It needs a model: some belief about how the present connects to the future. The model may be a formula, a pattern from history or a hunch. The prediction is only as good as the model, and a model cannot be checked until the future arrives.
Predictions fail in a different way. The inputs can all be correct and the outcome still differs, because the link between now and later was weaker than assumed or because something new happened.
Numbers that sit between
Some figures look like predictions and are really measurements. An option-implied expected move is one. It is computed from option prices trading now. It measures what the options market is charging for movement today. It does not say the market will move that much.
A base rate is another. It counts what happened in past cases that looked similar. That is a measurement of history. Treating it as a forecast adds an assumption that the future resembles the sample, which is the subject of a base rate is not a prediction.
A perp’s weekend move is a third. It is a market price on another venue. Calling it the level the stock opens at turns a measurement into a forecast without anyone doing the work.
Why the wording matters
The slide from one to the other usually happens in a verb. “The perps have the index up half a percent” is a measurement. “The index opens up half a percent” is a prediction. The data behind the two sentences is identical. The second one makes a claim the data cannot support.
A careful reader watches for that verb. A careful writer keeps to the first form and lets the reader decide what follows from it.
What each is for
Measurements build the picture. Decisions about the future belong to the trader, who knows the account, the horizon and the risk being carried. A tool that measures well and stays out of forecasting leaves that judgment where it belongs.
Where NoVo sits
NoVo is a readout. It measures and reports, and it does not predict. Dr. NoVo, a markets SI, writes his reads from the measured data and declines to forecast, for the reasons in why a markets SI refuses to forecast. Every reading on the MCP & API carries as_of, age_seconds and as_of_kind, so a number arrives with its age and its kind attached.