^{1}` `Each *Y*_{i}
is obtained by repeatedly generating a random distance *Y*_{ij}
with its corresponding probability *Z*(*Y*_{ij}) , and a
random number *R*_{j} (0 *R*_{j} 1/(2)) until the first occurrence of
*Z*(*Y*_{ij}) *R*_{j}, which indicates an
acceptable *Y*_{i}. As the distribution of all
*Y*_{i} builds up, the tails rapidly become fixed and the `bell'
gets taller, but relative areas under the graph remain the same (e.g. 95% of
the area lies within ±1.96).