Methods of analyzing data are provided. An insulated housing of the lower connector also has opposite side-walls extending down to form a pair of stubby legs shorter than the elongate legs. The or each mask has a geometry which may vary in accordance with a user’s input whereby the user selecting a first point within a mask and a second point displaced therefrom causes the geometry of that mask to vary in relation to the displacement between the first and second points. A cruise control arm is also mounted on and rotatable about the shaft, and a linkage connects the control arm to the cruise control arm, which only moves between the neutral and forward positions.