| 摘要 |
PROBLEM TO BE SOLVED: To efficiently store the appearing frequency of a symbol string necessary for calculating composite probability. SOLUTION: Nodes 100 to 106 of a tree structure are provided with memories 120 to 126 for storing the appearing frequency of symbols necessary for calculating composite probability. Then, the numerator of probability is stored in the memory of a node and the denominator of probability is stored in the high-order memory of a node. At the time of calculating the composite probability that a following symbol B appears continually after a preceding symbol A, the nodes 101 and 104 are tracked from a route 100 to obtain the value of the numerator c (A, B) of probability from the memory 121 and the value of the denominator c (A) from the memory 124. With respect to the following symbol B, the node 102 is tracked from the route 100 to obtain the value of the numerator c (B) of probability from the memory 125 and the value of the denominator N from the memory 126. N is the total number of the symbols. |
