# Vanilla Gradient Descent for Oblique Decision Trees

arXiv: https://arxiv.org/abs/2408.09135 · HTML: https://mlsanity.com/paper/2408.09135/

## Key facts

- Cited by 6 papers in the map (data through 14 Oct 2026).
- Builds on 21 of its 42 references that are in the map.
- First posted on arXiv 17 Aug 2024.

## Builds on (most cited first, 21 of 21)

- [Proximal Policy Optimization Algorithms](https://mlsanity.com/paper/1707.06347/) (2017)
- [Soft Actor-Critic: Off-Policy Maximum Entropy Deep Reinforcement Learning with a Stochastic Actor](https://mlsanity.com/paper/1801.01290/) (2018)
- [Estimating or Propagating Gradients Through Stochastic Neurons for Conditional Computation](https://mlsanity.com/paper/1308.3432/) (2013)
- [Visualizing the Loss Landscape of Neural Nets](https://mlsanity.com/paper/1712.09913/) (2017)
- [On the Optimization of Deep Networks: Implicit Acceleration by Overparameterization](https://mlsanity.com/paper/1802.06509/) (2018)
- [StarCraft II: A New Challenge for Reinforcement Learning](https://mlsanity.com/paper/1708.04782/) (2017)
- [Distilling a Neural Network Into a Soft Decision Tree](https://mlsanity.com/paper/1711.09784/) (2017)
- [Programmatically Interpretable Reinforcement Learning](https://mlsanity.com/paper/1804.02477/) (2018)
- [Verifiable Reinforcement Learning via Policy Extraction](https://mlsanity.com/paper/1805.08328/) (2018)
- [Deep Neural Decision Trees](https://mlsanity.com/paper/1806.06988/) (2018)
- [Toward Interpretable Deep Reinforcement Learning with Linear Model U-Trees](https://mlsanity.com/paper/1807.05887/) (2018)
- [Adaptive Neural Trees](https://mlsanity.com/paper/1807.06699/) (2018)
- [The Tree Ensemble Layer: Differentiability meets Conditional Computation](https://mlsanity.com/paper/2002.07772/) (2020)
- [NBDT: Neural-Backed Decision Trees](https://mlsanity.com/paper/2004.00221/) (2020)
- [Conservative Q-Improvement: Reinforcement Learning for an Interpretable Decision-Tree Policy](https://mlsanity.com/paper/1907.01180/) (2019)
- [Neural Random Forests](https://mlsanity.com/paper/1604.07143/) (2016)
- [TripleTree: A Versatile Interpretable Representation of Black Box Agents and their Environments](https://mlsanity.com/paper/2009.04743/) (2020)
- [CDT: Cascading Decision Trees for Explainable Reinforcement Learning](https://mlsanity.com/paper/2011.07553/) (2020)
- [Oblique Decision Trees from Derivatives of ReLU Networks](https://mlsanity.com/paper/1909.13488/) (2019)
- [Learning Accurate Decision Trees with Bandit Feedback via Quantized Gradient Descent](https://mlsanity.com/paper/2102.07567/) (2021)
- [Learning Binary Decision Trees by Argmin Differentiation](https://mlsanity.com/paper/2010.04627/) (2020)

## Built on by (most cited first, 6 of 6)

- [LHT: Statistically-Driven Oblique Decision Trees for Interpretable Classification](https://mlsanity.com/paper/2505.04139/) (2025)
- [Hinge Regression Tree: A Newton Method for Oblique Regression Tree Splitting](https://mlsanity.com/paper/2602.05371/) (2026)
- [Approximation-Free Differentiable Oblique Decision Trees](https://mlsanity.com/paper/2605.07837/) (2026)
- [DiPRL: Learning Discrete Programmatic Policies via Architecture Entropy Regularization](https://mlsanity.com/paper/2605.18508/) (2026)
- [Hinge Regression Trees and HRT-Boost: Newton-Optimized Oblique Learning for Compact Tabular Models](https://mlsanity.com/paper/2605.23422/) (2026)
- [Adaptive Multi-Branching for Shallow Decision Tree Induction](https://mlsanity.com/paper/2608.29262/) (2026)

## Abstract (arXiv)

Decision Trees (DTs) constitute one of the major highly non-linear AI models, valued, e.g., for their efficiency on tabular data. Learning accurate DTs is, however, complicated, especially for oblique DTs, and does take a significant training time. Further, DTs suffer from overfitting, e.g., they proverbially "do not generalize" in regression tasks. Recently, some works proposed ways to make (oblique) DTs differentiable. This enables highly efficient gradient-descent algorithms to be used to learn DTs. It also enables generalizing capabilities by learning regressors at the leaves simultaneously with the decisions in the tree. Prior approaches to making DTs differentiable rely either on probabilistic approximations at the tree's internal nodes (soft DTs) or on approximations in gradient computation at the internal node (quantized gradient descent). In this work, we propose DTSemNet, a novel semantically equivalent and invertible encoding for (hard, oblique) DTs as Neural Networks (NNs), that uses standard vanilla gradient descent. Experiments across various classification and regression benchmarks show that oblique DTs learned using DTSemNet are more accurate than oblique DTs of similar size learned using state-of-the-art techniques. Further, DT training time is significantly reduced. We also experimentally demonstrate that DTSemNet can learn DT policies as efficiently as NN policies in the Reinforcement Learning (RL) setup with physical inputs (dimensions ≤32). The code is available at https://github.com/CPS-research-group/dtsemnet.
