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-  We estimated   by by , where , where is the total number of training
instances where is the total number of training
instances where and and is the number of these
where is the number of these
where . .
-  Good estimate except when   gets too small (e.g., goes to zero). gets too small (e.g., goes to zero).
-  m-estimate of probability:   ,
where ,
where is the prior estimate of the probability and is the prior estimate of the probability and is the
equivalent sample size is the
equivalent sample size
-  Can be interpreted as augmenting the   actual observations
by an additional actual observations
by an additional virtual samples distributed according to virtual samples distributed according to  
 
Patricia Riddle 
Fri May 15 13:00:36 NZST 1998