Volume follows price as auction state

Volume is not the force that moved price

The archive treats volume as participating size in motion, not as the force that produces a price move. That force is traders responding to new information, including the price path and volume itself.

Volume-price analysis, in this usage, means reading volume together with the price path to judge participation, surprise, and liquidity, rather than treating volume as the engine that moved the last print. The supplied argument treats volume as a response to price change rather than as a lead signal that precedes price.

First test whether price already moved

When price is unchanged, completed-trade momentum is treated as zero, including the uncommon case of a large-volume print at an unchanged price. Completed-trade momentum is directional money flow that exists only when a price change is printed.

Money flow is a momentum measure formed from volume multiplied by price change per unit of time, intended to show how many shares transacted at higher or lower prices. An unchanged price leaves that measure without direction.

Then score surprise, volatility, money flow, and depth

Volume still conveys how new information is absorbed in a way the price series alone cannot, because only volume shows how many participants are active at a given time.

Unexpected information is described as high information entropy and is generally associated with a rise in volume, sometimes a sharp one. Already-discounted information is generally associated with little volume change or a decline. Information entropy is how unexpected new information is to the crowd; higher surprise is generally associated with higher volume.

Volume is described as closely correlated with price volatility and therefore usable as a proxy for that volatility. Money flow, already defined as volume multiplied by price change per unit of time, is the third score and has no direction when price did not change.

Volume is used to infer whether market liquidity is present. Accurate pricing is described as less likely when too few participants are active. A larger number of market participants is associated with a narrower spread between bid and ask prices. Liquidity is whether enough participants are present for the last price to be treated as reliable; sparse activity makes accurate pricing less likely. The bid-ask spread is the gap between the best bid and offer, and it is described as narrowing when more participants join the auction.

Editorial interpretation: treat that last cluster as the book-depth score in the four-part market-state check. The same print is then read for surprise, for volatility, for money flow, and for whether enough of the book was present to treat the last price as reliable.

Convert the setup only after both checks

Editorial interpretation: a repeatable chart condition becomes a falsifiable trade hypothesis only after both steps. If price already moved and the print still shows surprise, a volatility companion, directional money flow, and enough participants for a reliable last price, the hypothesis can state what should happen next and what would prove the reading wrong. If the size arrived after the move, or arrived with no price change, the same condition is a weaker claim that volume led price.

The archive does not attach a performance result to that conversion. It supplies a reason to stop reading late or directionless size as confirmation.