Document Vector Hashing for Efficient Similarity Search

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Efficiently querying large collections of documents is challenging due to the high computational cost of calculating similarity between documents, making it expensive to find documents with similar content.

Innovation Solution

A system that represents documents as vectors in a multidimensional space, maps them to hyperboxes using a set of hash functions corresponding to different scales, and stores these mappings in a hash table, allowing for efficient retrieval of similar documents by hashing and associating vectors with their corresponding hash values.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If documents are stored with detailed vector representations for accurate similarity calculation, then query accuracy is improved, but storage space and query time increase

Engineering Contradiction:
Improvesimilarity measurement accuracyVSAvoidquery time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent segments the continuous multidimensional space into discrete hyperboxes at multiple scales. Each hyperbox represents a region containing documents with similar characteristics. By organizing documents into these segmented regions, the system enables efficient retrieval without requiring comparison with all documents, thus reducing query time while maintaining accuracy through multi-scale granularity.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces a hierarchical scale dimension to organize hyperboxes. Documents are organized not only by their content vectors but also by their position in the hierarchical scale structure. This additional dimensional organization allows the system to quickly navigate to relevant document groups at appropriate scales, reducing the search space and query time while preserving measurement accuracy.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Device complexity

If a fixed hash table structure is used for storing document vectors, then data structure simplicity is improved, but adaptability to varying document collections deteriorates

Engineering Contradiction:
Improvedata structure simplicityVSAvoidadaptability to document collection changes
Core Design Contradiction:
Device complexityVSAdaptability or versatility

Solution Approach 1:

The patent implements a dynamic hash table structure where hyperboxes can be created, merged, or split based on the characteristics of the document collection. The hash table adapts its structure dynamically as documents are added or removed, allowing the system to maintain optimal organization without requiring complete reorganization. This dynamic structure preserves simplicity while providing high adaptability to varying collection sizes and content distributions.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes the parameters of the hash table structure, specifically the number and size of hyperboxes, based on the document collection characteristics. The system can adjust the granularity and distribution of hyperboxes to match the actual data distribution, enabling the simple hash table structure to adapt to diverse and changing document collections efficiently.

Inventive Principle:
Principle #35Parameter changes

3Measurement precision

If multiple scales are used to define hyperboxes for better query precision, then query accuracy is improved, but hash table complexity increases

Engineering Contradiction:
Improvequery precisionVSAvoidhash table complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent implements a nested hierarchy ofhyperboxes where smaller-scalehyperboxes are contained within or related to larger-scalehyperboxes. This nesting structure allows the system to organize documents at multiple scales in a hierarchical manner, where each level provides different granularity. The nested structure enables efficient multi-scale queries without requiring completely separate hash tables for each scale, thus improving query precision while controlling complexity through hierarchical organization.

Inventive Principle:
Principle #7Nested doll (Nesting)

Data Source

PatentUS11442973B2System and method for storing and querying document collections
Publication Date: 2022.09.13 COGNYTE TECH ISRAEL LTD
  • US11442973B2 patent drawing
  • US11442973B2 patent drawing
  • US11442973B2 patent drawing

AI summary

A system for storing document collections in a manner that facilitates efficient querying. Each document vector is hashed, by applying a suitable hash function to the components of the vector. The hash function maps the vector to a particular hash value, corresponding to a particular hyperbox in the multidimensional space to which the vectors belong. The vector, or a pointer to the vector, is then stored in a hash table in association with the vector's hash value. Subsequently, given a document of interest, documents similar to the document of interest may be found by hashing the vector of the document of interest, and then returning the vectors that are associated, in the hash table, with the resulting hash value.