Table of Contents
Fetching ...

Planning vs Reasoning: Ablations to Test Capabilities of LoRA layers

Neel Redkar

TL;DR

This work investigates whether Low-Rank Adaptation (LoRA) layers can enhance reasoning and planning in language models. It introduces HashHop and HashChain Reasoning as deterministic benchmarks to differentiate planning from reasoning capabilities and to measure the impact of LoRA on each. The results indicate reasoning tasks benefit from low-rank representations and can be substantially improved with LoRA, while planning remains more challenging and shows limited gains, leading to the proposal of ELoRA (Entropy LoRA) which improves convergence and performance. Together, these findings suggest a separation of planning and reasoning in evaluation and point toward reasoning-focused, low-rank adaptations as a scalable path for extending latent capabilities, with future work spanning broader benchmarks and entropy-based priors.

Abstract

Low-Rank Adaptation (LoRA) layers have emerged as a promising approach for efficient model fine-tuning, but their capabilities and limitations have not been fully explored. This paper: 1) Investigates the fundamental question of whether LoRA layers are effective at increasing reasoning + planning abilities 2) We introduce HashChain Reasoning, a novel evaluation dataset that deterministically tests reasoning capabilities. Through systematic ablation studies on GPT-2, we demonstrate that reasoning capabilities appear to exist primarily in low-rank spaces and can be effectively enhanced using LoRA layers. The effective rank analysis of trained LoRA matrices reveals a 2-3x lower rank requirement for reasoning tasks compared to planning tasks, giving context on where LoRA layers would be effective. This also provides evidence for reasoning fundamentally preferring low-parameter spaces for generalization.

Planning vs Reasoning: Ablations to Test Capabilities of LoRA layers

TL;DR

This work investigates whether Low-Rank Adaptation (LoRA) layers can enhance reasoning and planning in language models. It introduces HashHop and HashChain Reasoning as deterministic benchmarks to differentiate planning from reasoning capabilities and to measure the impact of LoRA on each. The results indicate reasoning tasks benefit from low-rank representations and can be substantially improved with LoRA, while planning remains more challenging and shows limited gains, leading to the proposal of ELoRA (Entropy LoRA) which improves convergence and performance. Together, these findings suggest a separation of planning and reasoning in evaluation and point toward reasoning-focused, low-rank adaptations as a scalable path for extending latent capabilities, with future work spanning broader benchmarks and entropy-based priors.

Abstract

Low-Rank Adaptation (LoRA) layers have emerged as a promising approach for efficient model fine-tuning, but their capabilities and limitations have not been fully explored. This paper: 1) Investigates the fundamental question of whether LoRA layers are effective at increasing reasoning + planning abilities 2) We introduce HashChain Reasoning, a novel evaluation dataset that deterministically tests reasoning capabilities. Through systematic ablation studies on GPT-2, we demonstrate that reasoning capabilities appear to exist primarily in low-rank spaces and can be effectively enhanced using LoRA layers. The effective rank analysis of trained LoRA matrices reveals a 2-3x lower rank requirement for reasoning tasks compared to planning tasks, giving context on where LoRA layers would be effective. This also provides evidence for reasoning fundamentally preferring low-parameter spaces for generalization.

Paper Structure

This paper contains 14 sections, 1 equation, 7 figures, 2 tables.

Figures (7)

  • Figure 1: HashHop examples showing (a) a basic hash chain and (b) the structure of the new proposed HashChain Reasoning eval with multiple chains.
  • Figure 2: HashChain Reasoning graph with 3 chain (left) and 4 chain (right) accuracies showing performance as individual chain lengths increase. 4 chain reasoning accuracy demonstrated a significant increase with LoRA modules suggesting better reasoning generalization, with minimal fluctuation in 3 chain accuracy
  • Figure 3: Using the same metrics, Shannon entropy roy_effective_2007 (left) and cutoffs (right), there is about a 2x-3x decrease in effective rank for the HashChain reasoning task compared to the baseline HashHop task.
  • Figure 4: Calculating the effective rank of the LoRA matrix trained on the regular HashHop task. Shannon Entropy roy_effective_2007(left) gave a mean of 17.87 and a cutoff (right) gave a mean of 158
  • Figure 5: ELoRA architecture diagram. Similar to LoRA except for a small linear matrix with maximized entropy.
  • ...and 2 more figures