MTB > # Chapter 1 - Example 1
MTB > # Student takes 3 question multiple choice test 
MTB > # (each question has 4 items)
MTB > # Two models: K - knows what's going on, P - poor student
MTB > # initially these two models have probabilities .7 and .3
MTB > # each question has two results: C - correct or N - not correct
MTB > # if student is K, P(C) = .8; if student is P, P(C) is .4
MTB > # observe C N N
MTB > 
MTB > exec 'bayes_se'
 
INPUT NUMBER OF MODELS:
DATA> 2
 
INPUT NAMES OF MODELS (ONE NAME ON EACH LINE):
DATA> K
DATA> P
 
INPUT PRIOR PROBABILITIES OF MODELS:
DATA> .7 .3
 
INPUT THE NUMBER OF POSSIBLE OUTCOMES:
DATA> 2
 
INPUT THE NAME OF EACH OBSERVATION:
 (ONE OBSERVATION ON A LINE)
DATA> C
DATA> N
 
INPUT LIKELIHOODS OF EACH MODEL:

MODEL   
   1 

DATA> .8 .2

MODEL   
   2 

DATA> .4 .6
 
OBSERVATION NAMES:
 Row            OBS  OBS_NAME

   1   OUT_1            C    
   2   OUT_2            N    

TABLE OF PROBABILITIES OF MODELS AND OUTCOMES:

 Row  MODEL           NAME  PRIOR  OUT_1  OUT_2

   1      1   K               0.7    0.8    0.2
   2      2   P               0.3    0.4    0.6

MTB > notitle
MTB > exec 'bayes'
 
INPUT NUMBER OF OBSERVATIONS:
DATA> 3
 
INPUT OBSERVATIONS:
 (ONE OBSERVATION NAME ON A LINE:)
DATA> C
DATA> N
DATA> N

OUTCOME 
  C    

 Row  MODEL           NAME  PRIOR   LIKE  PRODUCT       POST
   1      1   K               0.7    0.8     0.56   0.823529
   2      2   P               0.3    0.4     0.12   0.176471

OUTCOME 
  N    

 Row  MODEL           NAME      PRIOR   LIKE    PRODUCT       POST
   1      1   K              0.823529    0.2   0.164706   0.608696
   2      2   P              0.176471    0.6   0.105882   0.391304

OUTCOME 
  N    

 Row  MODEL           NAME      PRIOR   LIKE    PRODUCT       POST
   1      1   K              0.608696    0.2   0.121739   0.341463
   2      2   P              0.391304    0.6   0.234783   0.658537
 
SUMMARY OF PRIOR AND POSTERIOR MODEL PROBABILITIES:

 Row  OBS_NO  OUTCOMES    PROB_M1    PROB_M2

   1       0             0.700000   0.300000
   2       1     C       0.823529   0.176471
   3       2     N       0.608696   0.391304
   4       3     N       0.341463   0.658537