From Siri to Cortana, computers have a voice so we might as well make them likeable

Creators of talking apps are having to craft personalities that appeal to everyone. It's a tall order, says Rhodri Marsden

GERTY, a computer character (voiced by Kevin Spacey) from the 2009's 'Moon'

How do we want our computers to sound? Authoritative and knowledgeable? Kind and soothing? Coy and self-deprecating? Maybe a bit like that bloke off The National Lottery Live?

As speech recognition and speech synthesis become more widespread, technology firms are having to make crucial decisions governing not only what computers say, but the personality they adopt while they're saying it. When Apple launched Siri in 2011, it was described as having "a light attitude...friendly and humble, with an edge", but that was more to do with what Siri said than what it sounded like.

These days I've got a choice of six Siris on my iPhone (male and female versions of American, Australian and British accents), and while the Australian female voice sounds like someone you wouldn't mind chatting to in a lift, the British male voice sounds like the insufferably smug toerag you'd walk away from at a party. Each to their own, of course – but creators of talking apps are having to craft personalities that appeal to everyone. It's a tall order. There's no question that some people are put off using voice features simply because they don't like the voice being used.

The rather one-dimensional speech of the sat nav was the first time many of us were offered a choice over the voice we wanted to hear from an electronic device. Some sounded more human than others; I'm quite fond of TomTom's male Irish voice ("Sean") because he doesn't sound like he's going to remonstrate with me for taking a wrong turning – unlike "Jane", the English female voice, who to me sounds like a driving instructor with an attitude problem.

The limited vocabulary of the satnav allows us to have more choice over those voices, but if you wanted a male version of, say, Microsoft's Cortana, you'd have no luck. Cortana's supposed attributes ("competent, caring, confident and loyal, always prepared to help, not bossy, eager to learn") were evidently deemed by Microsoft to be ones a male voice could not convey. They'll have user-tested this stuff intensely, and there are stories of how they discovered that boosting Cortana's confidence resulted in a marked upswing in positive human response – but you can't please everyone all of the time. That knowledge makes crafting AI supremely difficult.

As sociologist Clifford Nass explored in his 2010 book The Man Who Lied To His Laptop, we tend to treat computers as if they're human, whether we like it or not. If they flatter us, we feel better, so the voice doing the flattery is really important. A friend of mine told me how he chose a female-voiced trainer on his Nintendo Wii Fit, but one day he turned it on to discover that the programmers had mischievously got a male voice to say "your normal trainer couldn't make it today" before commencing the work-out. His annoyance at this is a testament to the closer relationships we're forming with artificial intelligences: little wonder that so much effort is being poured into making them more likeable.

I was recently told about a girl who became furious when her boyfriend changed his Siri voice from male to female. Imagine the jealousy in the future when we're able to dial up the exact personality type we want; a little more self-effacing, a little less prone to self-satisfaction, a little rounder on the vowels, a little less conversation, a little more action. Please.

Twitter.com/rhodri