A 1.3-point gap in sale-to-list sounds like proof, and it is already being repeated at kitchen tables as if it were. The comparison group behind it is 806 homes, and those 806 were not picked at random.
The Close reports on Compass pushing its Coming Soon phase toward 80% of listings, and then lays out the research each side is using to argue about it.
The Compass number: a July analysis "examined 296,966 listings and found a 100% median sale-to-list ratio among 806 listings excluded from Zillow, compared with 98.7% for listings that appeared there." Compass calls that 1.3-percentage-point gap a "Zillow Tax".
The same analysis found something that gets quoted far less: "Its analysis found no statistically significant difference in how quickly the two groups went under contract." A separate Compass study "estimated that homes first marketed as Private Exclusives or Coming Soons closed for 4.6% more after controlling for dozens of variables", and "The research covers Compass transactions, and the company notes that individual results may vary."
Zillow's evidence has the mirror-image problem. Its retained economist estimated lower prices for likely Compass private-network sales, but "His analysis used a proxy to identify those transactions rather than confirmed private-listing records". The Close's own conclusion is the sentence to keep: "Neither side’s research establishes that phased marketing will produce the same result for an individual seller."
“examined 296,966 listings and found a 100% median sale-to-list ratio among 806 listings excluded from Zillow, compared with 98.7% for listings that appeared there.”
This is the cleanest lesson in reading a statistic the industry has produced this year. The comparison group is 806 out of nearly 297,000, about three-tenths of one percent, and it is not a random sample — it is the set of homes that ended up off Zillow, and whatever put them there may be the same thing explaining the price. Both sides here are litigants in the same case, which is why who paid for a study belongs in the sentence when you repeat either number.
None of this makes phased marketing a bad strategy. It makes the label much stronger than the finding. If you are going to say it to a seller, be able to say where it came from and how many homes were in the small group — and build the habit generally: when a percentage sounds decisive, ask how big the smaller group was.