How similar are the Red & Green Quadratic functions?

Quadratic functions of the form are represented in the x,y plane on the right. Each quadratic function corresponds to a point in the p,q plane. Use the GREEN sliders to adjust the position of the green dot - and thus the green quadratic function in the x,y plane. Use the BLUE slider to set the size of the 'neighborhood' of the green dot. What questions can you ask? What conjectures seems to be worth exploring? Would it have been better to use a rectangular 'neighborhood' rather than a circular one? Why, or why not?