Manny Roman, ceo of Man Group, said computers would change the nature of work. "The shelves in the supermarket will be filled by automata, while scores of new jobs will be created," Roman told Reuters on the sidelines of a pensions conference.

New work would include hospital care for an increasingly aged population. "Pharma stocks will grow bigger in the indices, tech will grow bigger," Roman said.

Since taking over in 2013, Roman has looked to restructure Man Group after a near-90 percent collapse in its share price.

The firm's assets under management rose 35 percent last year to $72.9 billion (48 billion pounds), helped by four acquisitions which have reduced its reliance on computer-driven funds.

But Roman said computers helped to cut execution costs, a positive for investors, and model-driven quantitative funds would follow passive funds -- which track an index -- in attracting increasing levels of investment.

"Every single year you have more money going in (to passive funds) and I think for quant it's going to be very similar," he told the conference.

There have been some high-profile exits from hedge fund investment in the past year. Calpers, the biggest U.S. pension fund, scrapped its $4 billion hedge fund programme in September, saying it was too costly and complicated.    

But Roman said continued low rates in the developed world would spur demand for alternative investments.

"For every firm that withdraws, you have 10 new funds which put money into hedge funds."

(Editing by Robin Pomeroy)

By Carolyn Cohn