TThis dataset contains 1152 observation with four variables (y1 to y4). We generated this data set from the original_potat_data by the following instruction to use for the discrete factor analysis:
$$y1 = x1 - min(x1)$$
$$y2 = max(x2) - x2$$
$$y3 = max(x3) - x3$$
$$y4 = x4.$$