8. A system, comprising: a memory; a processor, coupled to the memory, the processor configured to: perform semantico-syntactic analysis of a natural language text to produce a semantic structure representing a set of semantic classes; associate a first semantic class of the set of semantic classes with a first value reflecting a specified semantic class attribute; identify a second semantic class associated with the first semantic class by a pre-defined semantic relationship; associate the second semantic class with a second value reflecting the specified semantic class attribute, wherein the second value is determined by applying a pre-defined transformation to the first value, wherein applying the pre-defined transformation comprises multiplying the first value by a pre-defined multiplier; evaluate a feature of the natural language text based on the first value and the second value; determine, by a classifier model using the evaluated feature of the natural language text, a degree of association of the natural language text with a particular category of a pre-defined set of categories; and perform, using the degree of association, a natural language processing operation.
8. A system, comprising: a memory; a processor, coupled to the memory, the processor configured to: perform semantico-syntactic analysis of a natural language text to produce a semantic structure representing a set of semantic classes; associate a first semantic class of the set of semantic classes with a first value reflecting a specified semantic class attribute; identify a second semantic class associated with the first semantic class by a pre-defined semantic relationship; associate the second semantic class with a second value reflecting the specified semantic class attribute, wherein the second value is determined by applying a pre-defined transformation to the first value, wherein applying the pre-defined transformation comprises multiplying the first value by a pre-defined multiplier; evaluate a feature of the natural language text based on the first value and the second value; determine, by a classifier model using the evaluated feature of the natural language text, a degree of association of the natural language text with a particular category of a pre-defined set of categories; and perform, using the degree of association, a natural language processing operation. 10. The system of claim 8 , wherein the semantic structure is represented by a graph comprising a plurality of nodes corresponding to the set of semantic classes and further comprising a plurality of edges corresponding to a plurality of semantic relationships.