You are changing lanes on a highway. No other vehicles are around. Do you still need to signal?

New York State law requires you to signal for at least 100 feet before you turn or change lanes. You must always signal, even when you don't see any other vehicles around. The vehicle you don’t see could be the most dangerous. [Turns, Chapter 5 Intersections and Turns, Part 2 – Rules of the Road, New York State Driver's Manual]