Boston officials use Big Data to find deceptive rental ads, unsafe units

Move-in day was in full swing on Wadsworth Street Thursday. David L Ryan/Globe Staff

Boston officials are testing a new method that draws on Big Data techniques to find deceptive apartment advertisements — and to identify potentially unsafe units.

The city recently began running computer programs that scan online apartment listings, primarily on Craigslist, and compare the information against city assessing records to make sure the ads don’t oversell the unit — exaggerating the number of bedrooms or bathrooms, for example.

The programs also scan for certain words and phrases and spit out a “risk score,” indicating whether there is a high or low probability that a listing is advertising a property that might violate regulations.

For example, a listing might get a higher risk score if an ad’s wording suggests that tenants’ bedrooms would be in a basement or an attic — spaces that are sometimes prohibited from being bedrooms without renovations and special permits.

Some ads have been for “a relatively small property with just a few bedrooms, and the listing says, ‘Hey, this is great for six students’ or ‘There’s basement that can be used for an extra couple of bedrooms,’” said Jascha Franklin-Hodge, the city’s chief information officer. “Those were concerning for us.”

Listings that the computer programs flag as potentially problematic are being investigated further by officials at Boston’s Inspectional Services Department.

If the city officials confirm that ads placed by real estate brokers are deceptive, the cases would be turned over to the state’s Division of Professional Licensure, an agency that has the power to discipline brokers, including by revoking licenses.

William Christopher, commissioner of the city’s inspection department, said that while punitive action will be taken against brokers when necessary, that’s not the goal.

“We want to let brokers know there are rules that have got to be followed and to educate them,” said Christopher.

Christopher said the effort has already turned up several cases of what city officials strongly believe to be intentionally misleading ads. He declined to provide more details, saying that the investigation into those listings is ongoing.

Officials said they are particularly concerned for the large number of college students who go online to rent apartments off campus. For many, it’s their first time renting an apartment and many are unaware of, or unconcerned with, tenants’ rights and the safety of their apartments. Some students from out of state even sign leases without having visited the unit in person.

“We have heard of cases where someone showed up to move into the apartment and they said, ‘This is not the apartment in the pictures that were sent to us,’” said Christopher.

The state’s Division of Professional Licensure routinely fields complaints from tenants who rent a unit that “wasn’t as promised,” said Chris Goetcheus, a spokesman for the agency. “Especially at this time of year, and even earlier, as students and other tenants are securing their housing.”

City officials emphasized the vast majority of real estate brokers and landlords follow the law.

The officials also acknowledged the computer programs will likely flag ads where there are really no issues and will miss other listings that should raise concerns.

But officials said that as the staff investigate cases further, they hope to assess how well the computer programs are working and if tweaks can be made to improve their ability to pick out ads that are truly concerning.

“It’s another tool for us to use,” said Christopher. “We’re trying to use every tool in our books to provide tenants and students with safe clean housing as they move in.”