Costs
Part of Privacy-safe celebrity maps with verified dates and sources
Why do celebrity home prices never appear on this site?
What a figure gives away about a home: how a price, a date and a district combine into an address, and why this site publishes none of them.
This site publishes no figures, and not because money makes us squeamish. A figure tied to a property is one of the strongest locating facts there is.
An amount, a date, and a rough area often leave just one property that fits. That is the whole problem, and it is why the rule is a flat refusal rather than a judgment call.
This page explains how re-identification works, why individually harmless facts combine into a locating one, and what that means for how buildings can be written about honestly.
What to take away
- Re-identification is a combination problemno single fact locates a home, and three or four ordinary ones usually do.
- A figure is unusually powerful in that combination because it is nearly unique and it is time-stamped.
- Writing about buildings loses almost nothing by refusing all of this, because the interesting material is architectural.
How a combination narrows
Think of each published fact as a filter over the whole stock of buildings.
How much each fact narrows
- A cityvery little
- A neighborhood or districta lot
- Building type and perioda lot
- A distinctive featureoften decisive
- A photograph of exterioroften decisive
- An amount with a datefrequently unique
| Fact | Roughly how much it narrows |
|---|---|
| A city | Very little on its own |
| A neighborhood or district | A lot, and more than people expect |
| A building type and period | A lot in combination with area |
| A distinctive feature, described | Often decisive |
| A photograph of any exterior element | Often decisive |
| An amount with a date | Frequently unique by itself |
The mistake people make is assessing each fact alone. Each looks harmless. The set is what identifies, and the person assembling the set is not the person who published the individual pieces. This is why an editorial policy has to be about the set and not about any one item.
Why a figure is the strongest single element
Three properties make it powerful. It is nearly continuous, so it discriminates finely. It is time-stamped, which combines with a date to narrow further. And it appears in public records that are indexed and searchable, so it can be matched rather than merely guessed.
Figure plus date plus district
- A figure: nearly continuous, finely discriminating
- A date: time-stamped, narrows further
- A district: combines with the figure
- Result: generally a specific parcel
- Everything else attaches to that parcel
Add a date and a district to a figure and the result is generally a specific parcel. Everything else on the page then attaches to that parcel: the description of the plan, the photograph of the room, the note about the approach. A page that would have been architectural writing becomes a description of a specific private home.
That reasoning applies whether or not the writer intended it, and it applies to hedged versions too. An approximate figure with a range still narrows, and a range plus a district often narrows to the same answer.
What we do instead
Nothing important is lost. The material this site is actually about survives untouched: lot geometry, plan types, structure, alteration, and how public records work as systems.
- Records are described as systems rather than quoted from. What an assessment record measures is set out in what an assessment record measures, and what a permit file contains is in what a permit file shows.
- Buildings are treated as types, not instances, so nothing attaches to a parcel.
- Institutions are treated differently from homes, because an institution publishes its own location and would be unchanged if everyone associated with it left.
- Photographs are used only where they show a general condition rather than an identifiable place.
The general rule and its reasoning are set out in what we publish and what we refuse, and the map-specific version is in why there is no map here.
What the public record's own bodies say
Property records are public for a legal reason: interests in land must be legible so they can be relied on. That purpose is narrow; it is not a general license to compile.
New York City's property assessment page shows a body defining its own scope: New York City's property assessment page.
The national historic file makes the same distinction from the other direction: it describes buildings, and the reason its material is safe to use is that it is about the building's significance rather than about anyone living in it. Its scope is described at what the National Register is.
Where a designation is public, the fact of a status is public. That is different from assembling a set of facts to locate somebody, and the distinction is the whole of this site's editorial policy.
Common questions
Is it not all public anyway?
Some of it is available. Available and compiled are different things, and compiling is the act that creates the risk. A page that assembles the set has done work that no individual record did.
Does hedging a figure make it safe?
No. A range still filters, and a range combined with a date and an area usually filters to the same result as an exact figure.
Why publish anything about records at all?
Because understanding how these systems work is genuinely useful, and it can be taught without quoting a single entry. Everything on this site about records is about structure and method.
What would make a building publishable here?
Being an institution: publishing its own location, opening on a schedule, and being unchanged if everyone associated with it left. That distinction, and what a public designation does and does not mean, is worked through in what being on a list means.
