# US 2022/0035845 A1 · Search indexing using discourse trees > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2022/0035845 A1 - Document ID: US20220035845A1 - Status: Published application - Kind: A1 - Application number: 17/503,590 - Filed: 2021-10-18 - Published: 2022-02-03 - Earliest claimed: 2017-09-27 - Assignees: Oracle International Corporation - Applicants: Oracle International Corporation - Inventors: Boris Galitsky - Web page: https://patentgrep.com/patent/US20220035845A1 ## CPC - G06F 16/322: {Trees} - G06F 16/313: {Selection or weighting of terms for indexing} - G06F 16/3329: Natural language query formulation - G06F 16/3331: Query processing - G06F 40/211: Syntactic parsing, e.g. based on context-free grammar [CFG] or unification grammars - G06F 40/35: Discourse or dialogue representation - G06F 40/30: Semantic analysis - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract Systems, devices, and methods of the present invention create a searchable index that includes informative portions of text. In an example, a computer-implemented method creates a discourse tree from a body of text. For each non-terminal node in the discourse tree, the method identifies a rhetorical relationship associated with the non-terminal node. The method labels each terminal node associated with the non-terminal node as either a nucleus or a satellite. The method further accesses a rule associated with the rhetorical relationship, and selects, based on the rule, selects the fragment associated with the nucleus. The method creates a searchable index including the selected fragments. ## Claims ### Claim 1 A system comprising: a non-transitory computer-readable medium storing computer-executable program instructions; and a processing device communicatively coupled to the non-transitory computer-readable medium for executing the computer-executable program instructions, wherein executing the computer-executable program instructions configures the processing device to perform operations comprising: creating a discourse tree from fragments of text, wherein the discourse tree comprises a plurality of nodes, each non-terminal node representing a rhetorical relationship between two of the fragments of text, and each terminal node is associated with one or more fragments and is associated with a non-terminal node; for each non-terminal node of the discourse tree: identifying, from the discourse tree, a rhetorical relationship associated with the non-terminal node, accessing a rule corresponding to the identified rhetorical relationship, wherein the rule identifies for selection, based on the rhetorical relationship, one or more of (i) a corresponding nucleus elementary discourse unit or (ii) a corresponding satellite elementary discourse unit, and selecting, based on the rule, one or more of (i) the fragment of text associated with the nucleus elementary discourse unit or the (ii) fragment of text associated with the satellite elementary discourse unit; and creating a searchable index comprising multiple entries, each entry corresponding to a selected fragment. ### Claim 2 (depends on 1) The system of claim 1, wherein executing the computer-executable program instructions configures the processing device to perform operations comprising: determining, for each fragment of text, an additional question; receiving a query from an external device; searching, in each of the additional questions for matches corresponding to the query; and responsive to determining a match in the additional questions, providing a response to the external device. ### Claim 3 (depends on 1) The system of claim 1, wherein executing the computer-executable program instructions configures the processing device to perform operations comprising, for at least one non-terminal node: identifying the rhetorical relationship as either (i) contrast or (ii) an elaboration relationship; and responsive to determining that the rule specifies accessing the satellite elementary discourse unit, selecting the satellite elementary discourse unit. ### Claim 4 (depends on 1) The system of claim 1, wherein the rule specifies (i) selecting the fragments associated with the nucleus elementary discourse unit and (ii) discarding fragments associated with the satellite elementary discourse unit. ### Claim 5 (depends on 1) The system of claim 1, wherein executing the computer-executable program instructions configures the processing device to perform operations comprising, for at least one non-terminal node: identifying the rhetorical relationship as either (i) enablement, (ii) elaboration, or (iii) contrast; and responsive to determining that the rule specifies accessing the nucleus elementary discourse unit, selecting the nucleus elementary discourse unit. ### Claim 6 (depends on 1) The system of claim 1, wherein each rhetorical relationship is one of condition, contrast, or attribution. ### Claim 7 (depends on 1) The system of claim 1, wherein executing the computer-executable program instructions configures the processing device to perform operations comprising: determining, for each fragment, an additional question; and providing the additional questions to an external device. ### Claim 8 (depends on 1) The system of claim 1, wherein executing the computer-executable program instructions configures the processing device to perform operations comprising, for at least one non-terminal node: identifying the rhetorical relationship as either (i) a same unit or a (ii) joint relationship; and responsive to determining that the rule specifies accessing both (i) the nucleus elementary discourse unit and (ii) the satellite elementary discourse unit, selecting both (i) the nucleus elementary discourse unit and (ii) the satellite elementary discourse unit. ### Claim 9 (depends on 1) The system of claim 1, wherein executing the computer-executable program instructions configures the processing device to perform operations comprising, for at least one non-terminal node: identifying the rhetorical relationship as an attribution relationship, and responsive to determining that the rhetorical relationship does not represent a query by an author, selecting the nucleus. ### Claim 10 A system comprising: a non-transitory computer-readable medium storing computer-executable program instructions; and a processing device communicatively coupled to the non-transitory computer-readable medium for executing the computer-executable program instructions, wherein executing the computer-executable program instructions configures the processing device to perform operations comprising: creating, for an answer of a question-answer index comprising fragments of text, a discourse tree, wherein the discourse tree comprises a plurality of nodes, each non-terminal node representing a rhetorical relationship between two of the fragments of text and each terminal node is associated with one or more fragments of text; for each non-terminal node in the discourse tree: identifying, from the discourse tree, a rhetorical relationship associated with the non-terminal node, accessing a rule corresponding to the identified rhetorical relationship, wherein the rule identifies for selection, based on the identified rhetorical relationship, either a corresponding nucleus elementary discourse unit or a corresponding satellite elementary discourse unit, and selecting, based on the rule, one or more of (i) the fragment of text associated with the nucleus elementary discourse unit or (ii) the fragment of text associated with the satellite elementary discourse unit; and creating an index of additional questions comprising an entry corresponding to the selected fragment of text. ### Claim 11 (depends on 10) The system of claim 10, wherein executing the computer-executable program instructions configures the processing device to perform operations comprising: receiving a query from an external device; searching, in each question of the question-answer index, for a match corresponding to the query; responsive to determining that fewer than a threshold number of matches are available, searching for additional matches to the query in the index of additional questions; responsive to determining that fewer than an additional threshold number of additional matches are available in the index of additional questions, searching for further matches in each answer in the question-answer index; and providing the matches to the external device. ### Claim 12 (depends on 10) The system of claim 10, wherein executing the computer-executable program instructions configures the processing device to perform operations comprising, for at least one non-terminal node: identifying the rhetorical relationship as either (i) a same unit or a (ii) joint relationship, and selecting both (i) the nucleus elementary discourse unit and (ii) the satellite elementary discourse unit, wherein the rule specifies accessing both (i) the nucleus elementary discourse unit and (ii) the satellite elementary discourse unit. ### Claim 13 (depends on 10) The system of claim 10, wherein executing the computer-executable program instructions configures the processing device to perform operations comprising, for at least one non-terminal node: identifying the rhetorical relationship as an attribution relationship, and responsive to determining that the rhetorical relationship does not represent a query by an author, selecting the nucleus. ### Claim 14 (depends on 10) The system of claim 10, wherein each entry represents an additional question that can be answered by the respective answer. ### Claim 15 (depends on 10) The system of claim 10, wherein the rule specifies (i) selecting fragments of text associated with the nucleus elementary discourse unit and (ii) discarding fragments of text associated with the satellite elementary discourse unit. ### Claim 16 (depends on 10) The system of claim 10, wherein executing the computer-executable program instructions configures the processing device to perform operations comprising: determining, for each fragment, an additional question; receiving a query from an external device; searching, in each of the additional questions for matches corresponding to the query; and responsive to determining a match in the additional questions, providing a response to the external device. ### Claim 17 (depends on 10) The system of claim 10, wherein executing the computer-executable program instructions configures the processing device to perform operations comprising, for at least one non-terminal node: identifying the rhetorical relationship as either (i) contrast or (ii) an elaboration relationship; and responsive to determining that the rule specifies accessing the satellite elementary discourse unit, selecting the satellite elementary discourse unit. ### Claim 18 A non-transitory computer-readable storage medium storing computer-executable program instructions, wherein when executed by a processing device, the computer-executable program instructions cause the processing device to perform operations comprising: training a classification model by iteratively: providing one of a set of training data pairs to the classification model, wherein each training data pair comprises text and an expected classification of one or more of: a nucleus elementary discourse unit of a training discourse tree or a satellite elementary discourse unit of the training discourse tree; receiving, from the classification model, a determined classification that is indicative of either a nucleus elementary discourse unit or a satellite elementary discourse unit; calculating a loss function by calculating a difference between the determined classification and the expected classification; and adjusting internal parameters of the classification model to minimize the loss function; creating a discourse tree from fragments of an additional text, wherein the discourse tree comprises a plurality of nodes, each non-terminal node representing a rhetorical relationship between two of the fragments of the additional text and each terminal node is associated with one or more of the fragments of the additional text; and for each terminal node in the discourse tree, labeling the terminal node as either a nucleus elementary discourse unit or a satellite elementary discourse unit by applying the trained classification model to fragments of the additional text associated with one or more of the terminal nodes. ### Claim 19 (depends on 18) The non-transitory computer-readable storage medium of claim 18, wherein when executed by a processing device, the computer-executable program instructions cause the processing device to perform operations comprising: creating a discourse tree from a body of text comprising fragments, wherein the discourse tree comprises a plurality of nodes, each non-terminal node representing a rhetorical relationship between two of the fragments and each terminal node associated with one or more fragments; for each non-terminal node: identifying a rhetorical relationship associated with the non-terminal node; providing a fragment of text associated with the non-terminal node and the rhetorical relation to the classification model; and receiving, from the classification model, a classification indicating whether the fragment of text is informative or not informative; and creating a searchable index of additional questions comprising each of the fragments identified as informative. ### Claim 20 (depends on 19) The non-transitory computer-readable storage medium of claim 19, wherein when executed by a processing device, the computer-executable program instructions cause the processing device to perform operations comprising: receiving a query from an external device; searching, in each of question of a plurality of question-answer pairs, for matches corresponding to the query; responsive to determining that fewer than a threshold number of matches are available, searching, in the searchable index of additional questions, for additional matches to the query; responsive to determining that fewer than a threshold number of additional matches are available in the searchable index of additional questions, searching for further matches in each answer of the plurality of question-answer pairs; and providing a response to the external device.