What makes robots 'persuasive' to humans

Scientists are exploring how robots persuade and build trust with humans, which could guide the development of artificial intelligence (AI) in the next generation of socially assistive machines to aid health care and other fields.

"My research aims to uncover behaviours and approaches that cause robots to be more persuasive to people," said Shane Saunderson, a PhD candidate at the University of Toronto in Canada.

"That can manifest as body language, or verbal strategies to approach people," Saunderson said.

Under the supervision of Associate Professor Goldie Nejat, Saunderson conducted an exploratory study of persuasion strategies to observe which methods would most influence a human's decision.

The top two strategies to emerge were an "emotional" approach and a "logical" one, said Saunderson.

Their experimental design, described in the journal IEEE Robotics and Automation Letters, featured two competing commercial robots named Leia and Luke and a jar of jelly beans.

Two hundred human participants were asked to write down their best estimate of how many jelly beans were in the jar.

The had to take into consideration the two differing suggestions provided by the robots, which attempted to influence the participants' guess using one of 10 randomly selected persuasion strategies.

These strategies ranged from critical to the friendly, researchers said.

Although Saunderson assumed the logical strategy would win, it was edged out by the emotional strategy.

"You see people increase their level of social connection with the robot. It indicates that we imbue robots with social agency when they interact with us using human-like social characteristics," he said.

Saunderson acknowledges that many may see the concept of AI-enabled robots with the ability to influence people as ominous.

However, "our lab is focusing on a lot of the good things that can be done -- social support in elder care, for example."