The nodereference says:
Scale: The scale setting controls the overall scale of the noise pattern generated. Increasing the scale value makes pattern larger overall
You should mention that the scale input is a vector which is useful for stretching the noise.
But use with care, all 3 components must be non zero.
If a scalar is used, the converted vector seems to be divided by sqrt(3), since dividing the input vector by a constant,
or using the same constant as scale input, gives the same output.