NEW YORK — For decades, efforts to standardize the data used to describe for-sale homes have been delayed and derailed by differing local customs, preferences, technologies and terminology.

Something as seemingly simple as defining a consistent way to count the number of bathrooms in a home has proven a monumental challenge given the patchwork landscape of more than 900 multiple listing services across the U.S.

And that means real estate consumers sometimes see conflicting information across various websites on square footage, the number of bedrooms and bathrooms, and other real estate descriptors because of inconsistencies in the reporting, translation and display of real estate data.

Enter the Data Dictionary, a project by an industry standards organization that seeks to create some common vocabulary for fields used to represent real estate data in MLSs.

Board members for the Real Estate Standards Organization (RESO), a group that has a mission to foster the development and use of data standards across the real estate industry, will meet in April to consider formal adoption of the Data Dictionary, and the board hopes adoption of the terminology will be rapid and far-reaching.

Born out of a National Association of Realtors effort to create a common way for the industry to share data — known as the Real Estate Transaction Standard — RESO has developed as a separate company to drive industry adoption for data standards. The group has developed bylaws and intellectual property agreements, and is awaiting federal approval for its ability to gather funds from its members.

Rebecca Jensen, CEO for the MLS since 2007 who was appointed as the chairperson for the RESO board in January 2011, said during an MLS issues discussion at the Real Estate Connect conference last week, "We’re very close to having the first Data Dictionary across the industry."

Jensen said there is "buy-in by a lot of key performers for the industry," and there "is a lot of momentum in the industry" to adopt data standards.

The Data Dictionary will describe various common field names in MLS entries, provide definitions for those fields, note data types, and may also outline which values are allowed to be entered into those fields, according to Jensen.

Those with input into the Data Dictionary include a variety of MLS organizations, vendors and consultants, she said, among them, California Regional Multiple Listing Service, Rapattoni and LPS.

"We have (more than) 900 MLSs (and they) all describe the data in a little bit different way," Jensen said. "We just need a common way to describe it."

The number of bathrooms in a home has been a particularly troublesome field to uniformly define because it can be represented in decimals and fractions, for example, depending on which bathroom fixtures are present in the room.

The Data Dictionary addresses this age-old problem by breaking down the number of bathrooms into separate fields:

  • baths total;
  • baths full;
  • baths half;
  • baths three-quarter;
  • baths one-quarter.

"Baths Total" is a text value that can display the count based on an MLS’s preference, Jensen noted. "This arrangement was agreed by the big data movers who see lots of data from across the country. This method gives the most flexibility while still maintaining accuracy."

Michael Wurzer, president and CEO of FBS, a real estate vendor that created the flexmls Web MLS system, who participated in the MLS panel discussion, said there has long been "this dream of plug and play" that has been the impetus for data standards, as it could potentially open the doors for more innovation in the MLS industry by allowing vendors to build tools that could be adopted across the country rather than in a piecemeal fashion.

What if there was a data socket (a standardized platform) that different developers could create products on top of? he said, so that technology was "one-size-fits-all."

As an executive for an MLS vendor, Wurzer noted that standards can be a tough sell, as "the idea of plug-and-play (technology) is a threat to MLS vendors. Differing MLS standards across the country has made it difficult for new entrants to quickly take root, he said. "It is hard for those third parties sometimes to come into those markets and do something that makes sense."

Even so, Wurzer said that standards are unavoidable for the industry, and he has been a proponent for the effort and previously served as chairman for the RESO board. "Even though that’s going to bring a lot of competition in our markets, to our products, it’s something we’re inviting because it’s the future. You can’t really innovate in the long term with one vendor."

While agreeing to a common vocabulary and definitions for data fields may be the easy part, Jensen said there is a challenge when it comes to unifying data fields that are directly related to MLS rules.

For example, she said "it’s relatively easy to say a bedroom is a number," but "days on market" may be calculated in many different ways based on the particular rules of an MLS. "It’s easy to do the technical part of (defining data fields) but rules are a whole new game," she said.

Greg Robertson, a longtime industry tech vendor whose W&R Studios company created social bookmarking tool Dwellicious, said another problem is that MLSs tend to be slow-moving entities, and even with data standards there can be a lengthy approval process for new technologies and contracts. "I don’t know if (data standards are) really going to help get things faster to market because of the permissioning process," he said.

Jensen queried audience members about using standardized technology contracts with vendors to speed the implementation of new technologies.

The concept of building plug-and-play technologies, accessible to all MLSs, may still be in the distance, Jensen also said, as the Data Dictionary is currently focused on only "the most commonly used fields that we can agree on," she said. "Creating the initial standard is just the first step."

Wurzer said that no matter how the Data Dictionary defines the fields, local MLSs will still be able to "implement their local terminology on top of a standard dictionary definition," so local customs can coexist with the new definitions.

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