Log-Linear Model Initialization via N-Gram Backoff

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Training log-linear language models on large datasets using convex optimization methods is computationally expensive, and existing methods for initializing these models from backoff n-gram models do not fully leverage the potential of additional linguistic and non-linguistic features to improve performance.

Innovation Solution

The method involves obtaining an n-gram language model, determining features and weights for a log-linear model based on the n-gram parameters, and using these to generate a log-linear model that can be trained to improve transcription accuracy for utterances, incorporating backoff features and non-linguistic context to enhance performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If log-linear language models are trained on large datasets using convex optimization methods, then model accuracy and performance are improved, but computational cost and training time increase significantly

Engineering Contradiction:
Improvetranscription accuracyVSAvoidcomputational cost
Core Design Contradiction:
Measurement precisionVSUse of energy by stationary object

Solution Approach 1:

The patent applies preliminary action by pre-training an n-gram language model on large datasets before initializing the log-linear model. This pre-computed n-gram model serves as a foundation, allowing the log-linear model to start with informed parameter estimates rather than random initialization, thereby reducing the computational burden of subsequent training while maintaining or improving transcription accuracy.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent uses the n-gram language model as an intermediary between raw training data and the final log-linear model. The n-gram model acts as a mediator that processes large datasets and extracts useful patterns, which are then transferred to initialize the log-linear model parameters, reducing the direct computational burden on the log-linear training process.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Productivity

If traditional n-gram models are used for speech recognition, then computational efficiency is maintained, but the ability to incorporate additional linguistic and non-linguistic features is limited

Engineering Contradiction:
Improvecomputational efficiencyVSAvoidfeature incorporation capability
Core Design Contradiction:
ProductivityVSAdaptability or versatility

Solution Approach 1:

The patent applies parameter changes by transforming the model formulation from traditional n-gram to log-linear parameters. This parameter transformation enables the model to incorporate additional linguistic and non-linguistic features while maintaining computational efficiency. The log-linear parameterization allows flexible feature integration without the exponential complexity growth associated with traditional approaches.

Inventive Principle:
Principle #35Parameter changes

3Adaptability or versatility

If log-linear models are initialized from scratch without using pre-trained n-gram models, then model flexibility is maintained, but training time and computational resources are significantly increased

Engineering Contradiction:
Improvemodel flexibilityVSAvoidtraining time
Core Design Contradiction:
Adaptability or versatilityVSLoss of time

Solution Approach 1:

The patent applies preliminary action by pre-training an n-gram language model on large datasets before initializing the log-linear model. This pre-computed n-gram model serves as a foundation, allowing the log-linear model to start with informed parameter estimates rather than random initialization, thereby reducing the computational burden of subsequent training while maintaining or improving transcription accuracy.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentUS10134394B2Speech recognition using log-linear model
Publication Date: 2018.11.20 GOOGLE LLC
  • US10134394B2 patent drawing
  • US10134394B2 patent drawing
  • US10134394B2 patent drawing

AI summary

Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, relating to generating log-linear models. In some implementations, n-gram parameter values derived from an n-gram language model are obtained. N-gram features for a log-linear language model are determined based on the n-grams corresponding to the obtained n-gram parameter values. A weight for each of the determined n-gram features is determined, where the weight is determined based on (i) an n-gram parameter value that is derived from the n-gram language model and that corresponds to a particular n-gram, and (ii) an n-gram parameter value that is derived from the n-gram language model and that corresponds to an n-gram that is a sub-sequence within the particular n-gram. A log-linear language model having the determined n-gram features is generated, where the determined n-gram features in the log-linear language model have weights that are initialized based on the determined weights.