Deloitte's national managing partner of analytics, Anthony Viel, said Westpac's KnowMe platform was "ahead of the game" in Australia. He also said customers felt happier when they thought banks were anticipating and responding to their needs.
"But it's one thing to say you're doing it and another to actually do it," he said. "I can throw an offer to 100 per cent of my customer base but it's not worth anything if they don't convert. "This isn't breaking new ground globally. There would certainly be banks in the US and the UK who would be doing this at the present."
Mr Viel said Westpac's program came close to crossing the "creepy line" made famous by US retailer Target, which used the shopping baskets of female customers to determine when they were pregnant before sending customised vouchers to boost business.
"I personally don't think this is crossing the creepy line because as a customer you want to be serviced in the most efficient way possible and you don't mind responding to something you need or want," he said.
"If you save the customer a lot of money then the creepy line moves. If you get it wrong then the creepy line becomes ever more present."
Gartner managing vice president Ian Bertram agreed that Westpac's KnowMe program didn't cross the creepy line but said it performed the same task as Target's much-maligned big data system.
"Organisations are going to have to work out the timing of all their offers because it can become a little bit creepy," he said. "If I'm searching on the website and within 30 seconds I have someone call me asking if I'm interested in a home loan then you start asking 'Who's watching me?' Timing and relevance are all key factors."
Banks are not the only businesses investing in big data to get an edge on their rivals. Woolworths recently paid $20 million for a 50 per cent stake in data analytics company Quantium.
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