Merrill Edge, Bank of America's discount brokerage unit, is rolling out its own robo advisory business - a response to investors’ demand for low-cost advice in an era of low expected returns. 'Merrill Edge Guided Investing' will combine Merrill Edge’s online brokerage platform with Merrill Lynch’s human advisers’ wealth-management expertise.

The automated service is “a natural extension of our investment offerings from Merrill Lynch,” designed to meet the needs of current clients interested in automated advice and those seeking a robo adviser with a bit more human touch, said Aron Levine, head of Merrill Edge. Mr. Levine said the input its robo service will receive from the staff of Merrill’s chief investment officer will differentiate it from some existing services that rely more heavily on algorithms.