too large the fruit falls and does not symmetrically lie on the
belts with respect to the y-axis and the head diameter is
therefore not measured. If the a is too small, the fruit shoulder
might stay at the rim, and diameter measurement does not
occur. The appropriate inclination angle (a) therefore needed
to be determined. Eq. (1) (Peleg, 1985) suggests the estimate of
diameter of separation (X12 and X23) between java apple fruits
of adjacent grades from the mean and the standard deviation
of each adjacent grade. The values of X12 and X23 are given in