Let's Go links Port Authority patrons with city neighborhoods

Thanks to Carnegie Mellon’s Language Technologies Institute (LTI), there is no excuse for getting stranded at the Waterfront on a Sunday night. Since March 2005, Let’s Go, a dialogue system developed at the LTI, has been helping Pittsburgh Port Authority’s patrons get where they need to be at all hours of the day and night.

In 2002, the National Science Foundation approved a grant for Let’s Go, giving Maxine Eskenazi and Alan Black, associate professors of computer science, $650,000 to work with the Port Authority on the development of a spoken dialogue system.

The two work with a team comprising several of the LTI’s faculty members and graduate students, along with customer service experts at the Port Authority.

According to research assistant and Ph.D. candidate Antoine Raux, Let’s Go was originally intended to assist what Raux called “nonstandard” populations, meaning those who normally have problems with technology, such as the elderly and non-native English speakers.

However, the system now serves anyone who calls the Port Authority’s regular customer service line. Patrons need only call after hours to interact with Let’s Go’s system.

“We did a presentation for the Port Authority, and they asked us if we could put that online for customers,” Raux said. After three years of development, Let’s Go started talking to the Port Authority’s customers.

During the day, patrons who call are connected to a human customer service representative. But when riders call at times that the Port Authority office isn’t open, Let’s Go will assist the riders.

“[The representatives] do wonderful, fantastic jobs of giving information,” Eskenazi said. “We don’t replace them, we just answer the phone when they’re not working.”

Both the LTI and the Port Authority benefit from the collaboration. The Port Authority gets to serve its customers virtually 24 hours a day, seven days a week, and the faculty and students developing Let’s Go get heaps of data that tell them how the system is performing.

And data is something Let’s Go has certainly produced much of, garnering somewhere in the vicinity of 30,000 calls since it started working the late shift almost two years ago.

“When you call, we abide by a legal experimental disclaimer that you are being recorded for research purposes to better the system,” Eskenazi said. She noted that the system has been quite successful, averaging about 40 to 50 calls each night.

Having been originally designed for people who normally have trouble with technology, the system is interactive in many ways.

Just as a human can sense frustration and subsequently change the way he or she asks questions, Eskenazi and her co-workers ensured that Let’s Go can do the same.

“We train the system with normal speech,” Eskenazi said. “When someone gets frustrated, their speech changes and recognition may not work as well. To avoid this situation, when we think we are getting in an impasse we use a back-off strategy.”

The back-off strategy is a mechanism that Let’s Go features to keep user frustration from altering their experience.

In an ongoing effort to improve the quality of the system, Eskenazi and Black will host a Let’s Go lab, where the two will work with other researchers in their field to study and analyze the program.

According to Eskenazi, faculty from Columbia, Stanford, and MIT will contribute to the project by analyzing pools of data and performing studies on a modified version of the system.

“[An] advantage is that we have complete control of the system,” Raux said. “The Port Authority trusts us to keep the user in mind.”

Right now the system has only one line and covers only certain heavily traveled bus lines along Pittsburgh’s east end. The system specifically covers those that serve Shadyside, Squirrel Hill, and Oakland. Eskenazi, Raux, and their colleagues are looking into expanding the system by installing more lines and extending the coverage to other neighborhoods.

Though the system currently has limitations, Eskenazi views the work that she and her team are doing with Let’s Go as crucial to the Port Authority and to research at the LTI.

“If we were not there, there would be no one answering the phone,” Eskenazi said.