1. A confidence computing method, comprising: (a) generating a syntactical parse tree for an interpreted text string, the parse tree including a plurality of sub-trees, each of the sub-trees representing a corresponding section of the interpreted text string; (b) for each sub-tree, determining whether the respective sub-tree is accurate; and (c) subsequent to a determination, for at least one of the sub-trees, that the at least one sub-tree is accurate, providing an output based on the at least one sub-tree's at least one corresponding section of the interpreted text string.