A number is a chain, not a guess#

Challenge a guess and there is nothing to point at#

Restate it more confidently, or abandon it.

There is no third move.

From something you know to something you don’t#

Suburbs → routes per suburb → stops per route → bus stops

Not the only route: kilometres of road and stops per kilometre is another chain; buses in the fleet and stops per bus’s run is a third.

Four things a chain gives you#

• Inspectable — every link is a claim you can examine on its own
• Checkable — each step must produce the unit it claims
• Local — disagreement lands on one link, not the whole guess
• Defined — you cannot decompose a target you have not pinned down

Stops-per-route × suburbs gives nothing at all#

Stops-per-route × routes = stops.

Stops-per-route × suburbs = nothing at all.

Passing units tells you the chain is not nonsense. It does not tell you the chain is right — a stop served by four routes still gets counted four times.

How many bus stops are there in the ACT network?#

2,581 rows · 2,581 distinct stop_id · 2,570 distinct stop_name

ACT Government open data, queried directly while this session was prepared.

A July 2017 snapshot of stop records#

Not a 2027 count — the most recent open extract; the current list lives behind a GTFS access key.

Not a count of physical stops, either — a count of stop records. Whether a stop served by four routes is one thing or four, the dataset does not say.

An estimate whose target is undefined is not precise enough to be wrong#

Two careful people can build different honest chains for the same brief, and both be right about their own question.

Next: the assumption you circled, and what it was really carrying.

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