REDMOND, Washington, April 4 (Reuters) - As Microsoft

CEOs past and present gathered here to celebrate the

company's 50th birthday, one leader said he is targeting a

particular metric's improvement to guide his strategy on

artificial intelligence.

Mustafa Suleyman, chief executive of Microsoft AI, said his

consumer and research division is tracking the usual measures of

adoption for the company's AI assistant called Copilot. These

include daily and weekly active users, distribution, and usage

intensity for Copilot's consumer offering, he said.

But Suleyman's interest lies elsewhere.

"I really, really focus the team on SSR, the rate of

successful sessions," he said in an interview.

In an older era when consumers gave less real-time feedback

on software, the time they spent with a product -- on social

media, for instance -- or the problems they could solve

represented crude "proxies for quality," he said.

"Now, we actually get to learn from the anonymized logs and

extract the sentiment," said Suleyman, who joined Microsoft ( MSFT )

about a year ago after leading the startup Inflection AI.

Suleyman was one of the only Microsoft ( MSFT ) executives other than

former CEOs Bill Gates and Steve Ballmer and current CEO Satya

Nadella to speak on stage at Microsoft's ( MSFT ) Friday event at its

Redmond, Washington, headquarters.

Suleyman said Microsoft ( MSFT ) has tasked an AI model itself to

assess such sentiment and help determine Copilot chats' SSR.

"Over the last four months, it's gone up dramatically, and

that's what we optimize for," he said.

Suleyman declined to state the rate in absolute terms or

disclose other Copilot metrics.

The company last fall announced a more amiable voice for its

consumer Copilot and the ability to analyze web pages for users

as they browse.

On Friday, Microsoft ( MSFT ) demonstrated further features for

Copilot: personalized podcasts, a tool to help consumers

research complex queries, and eventually a look for Copilot that

can be custom to each user and conversation.

"I would definitely go for something that was cutesy," said

Suleyman, "like a little Furby-type thing."