Greenwich Synthetic Twin Property Comparisons
Explore Greenwich Synthetic Twin estimates, earlier comparable public sales, modeled price ranges, and an interactive map.
147 Old Church Road sold for $2.80M, 33.0% below its $4.18M out-of-sample expectation. Its 50% likely zone is $3.62M–$4.83M; the 80% broader range is $2.89M–$6.05M. The model used 4,813 training, 1,054 calibration, and 1,055 untouched test sales; test median error was 16.5%. This is a market comparison, not an appraisal.
What this chart measures
Synthetic Twin compares a completed Greenwich sale with earlier public-record transactions that most closely resemble it, while keeping the target sale out of its own estimate.
How to read it
The center is a pre-sale public-record expectation, not an appraisal. The likely and broad ranges are calibrated on later held-out sales, and the listed twins are adjusted to the target date.
Why it matters
Property-level context can reveal what a town-wide median cannot. The remaining gap also highlights the private features—condition, views, privacy, and terms—that public records cannot observe.
Latest reading: 147 Old Church Road sold for $2.80M, 33.0% below its $4.18M out-of-sample expectation. Its 50% likely zone is $3.62M–$4.83M; the 80% broader range is $2.89M–$6.05M. The model used 4,813 training, 1,054 calibration, and 1,055 untouched test sales; test median error was 16.5%. This is a market comparison, not an appraisal.
The Address Index is independent market intelligence based on public and source-linked records. It is not an appraisal, brokerage opinion, or investment recommendation.
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