# Angle-based Search Space Shrinking for Neural Architecture Search

arXiv: https://arxiv.org/abs/2004.13431 · HTML: https://mlsanity.com/paper/2004.13431/

## Key facts

- Cited by 32 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 28 Apr 2020.

## Built on by (most cited first, 30 of 32)

- [Can GPT-4 Perform Neural Architecture Search?](https://mlsanity.com/paper/2304.10970/) (2023)
- [BossNAS: Exploring Hybrid CNN-transformers with Block-wisely Self-supervised Neural Architecture Search](https://mlsanity.com/paper/2103.12424/) (2021)
- [Searching the Search Space of Vision Transformer](https://mlsanity.com/paper/2111.14725/) (2021)
- [AutoML in the Age of Large Language Models: Current Challenges, Future Opportunities and Risks](https://mlsanity.com/paper/2306.08107/) (2023)
- [Neural Architecture Search with Random Labels](https://mlsanity.com/paper/2101.11834/) (2021)
- [Stronger NAS with Weaker Predictors](https://mlsanity.com/paper/2102.10490/) (2021)
- [Generalizing Few-Shot NAS with Gradient Matching](https://mlsanity.com/paper/2203.15207/) (2022)
- [Auto-HeG: Automated Graph Neural Network on Heterophilic Graphs](https://mlsanity.com/paper/2302.12357/) (2023)
- [K-shot NAS: Learnable Weight-Sharing for NAS with K-shot Supernets](https://mlsanity.com/paper/2106.06442/) (2021)
- [BN-NAS: Neural Architecture Search with Batch Normalization](https://mlsanity.com/paper/2108.07375/) (2021)
- [Analyzing and Mitigating Interference in Neural Architecture Search](https://mlsanity.com/paper/2108.12821/) (2021)
- [Demystifying the Neural Tangent Kernel from a Practical Perspective: Can it be trusted for Neural Architecture Search without training?](https://mlsanity.com/paper/2203.14577/) (2022)
- [RepGhost: A Hardware-Efficient Ghost Module via Re-parameterization](https://mlsanity.com/paper/2211.06088/) (2022)
- [One-Shot Neural Ensemble Architecture Search by Diversity-Guided Search Space Shrinking](https://mlsanity.com/paper/2104.00597/) (2021)
- [GreedyNASv2: Greedier Search with a Greedy Path Filter](https://mlsanity.com/paper/2111.12609/) (2021)
- [Partial Fine-Tuning: A Successor to Full Fine-Tuning for Vision Transformers](https://mlsanity.com/paper/2312.15681/) (2023)
- [SEKI: Self-Evolution and Knowledge Inspiration based Neural Architecture Search via Large Language Models](https://mlsanity.com/paper/2502.20422/) (2025)
- [Evolutionary Multi-objective Architecture Search Framework: Application to COVID-19 3D CT Classification](https://mlsanity.com/paper/2101.10667/) (2021)
- [CLOSE: Curriculum Learning On the Sharing Extent Towards Better One-shot NAS](https://mlsanity.com/paper/2207.07868/) (2022)
- [DetOFA: Efficient Training of Once-for-All Networks for Object Detection Using Path Filter](https://mlsanity.com/paper/2303.13121/) (2023)
- [Subnet-Aware Dynamic Supernet Training for Neural Architecture Search](https://mlsanity.com/paper/2503.10740/) (2025)
- [LENAS: Learning-based Neural Architecture Search and Ensemble for 3D Radiotherapy Dose Prediction](https://mlsanity.com/paper/2106.06733/) (2021)
- [When NAS Meets Trees: An Efficient Algorithm for Neural Architecture Search](https://mlsanity.com/paper/2204.04918/) (2022)
- [Reducing Neural Architecture Search Spaces with Training-Free Statistics and Computational Graph Clustering](https://mlsanity.com/paper/2204.14103/) (2022)
- [Revisiting Training-free NAS Metrics: An Efficient Training-based Method](https://mlsanity.com/paper/2211.08666/) (2022)
- [GeNAS: Neural Architecture Search with Better Generalization](https://mlsanity.com/paper/2305.08611/) (2023)
- [Training BatchNorm Only in Neural Architecture Search and Beyond](https://mlsanity.com/paper/2112.00265/) (2021)
- [LISSNAS: Locality-based Iterative Search Space Shrinkage for Neural Architecture Search](https://mlsanity.com/paper/2307.03110/) (2023)
- [CARL: Causality-guided Architecture Representation Learning for an Interpretable Performance Predictor](https://mlsanity.com/paper/2506.04001/) (2025)
- [SpaceEvo: Hardware-Friendly Search Space Design for Efficient INT8 Inference](https://mlsanity.com/paper/2303.08308/) (2023)

## Abstract (arXiv)

In this work, we present a simple and general search space shrinking method, called Angle-Based search space Shrinking (ABS), for Neural Architecture Search (NAS). Our approach progressively simplifies the original search space by dropping unpromising candidates, thus can reduce difficulties for existing NAS methods to find superior architectures. In particular, we propose an angle-based metric to guide the shrinking process. We provide comprehensive evidences showing that, in weight-sharing supernet, the proposed metric is more stable and accurate than accuracy-based and magnitude-based metrics to predict the capability of child models. We also show that the angle-based metric can converge fast while training supernet, enabling us to get promising shrunk search spaces efficiently. ABS can easily apply to most of NAS approaches (e.g. SPOS, FairNAS, ProxylessNAS, DARTS and PDARTS). Comprehensive experiments show that ABS can dramatically enhance existing NAS approaches by providing a promising shrunk search space.
