In  the  neural  network  classification  algorithm,  Tiberius  predicts  positive  numbers  for  one  class  and  negative  numbers  for  the  other  class.  Zero  is  known  as  the  'decision  boundary'.
 
The  best  solution  is  the  one  with  the  minimum  'cost',  which  can  be  considered  a  monetary  value.  It  may  not  matter  if  we  get  9  non-responders  to  a  mail  campaign  that  costs  $1  per  mailing  if  the  10th  will  repspond  and  result  in  a  $11  sale.  We  have  still  made  money.
 
This  table  allows  costs  to  be  entered  so  that  Tiberius  can  find  the  appropriate  decision  boundary  in  order  to  minimise  the  cost.