Computational Chemistry
Unified framework converts handwritten chemical expressions to structured graph representations

Unified Framework for Handwritten Chemical Expressions

Proposes a unified statistical framework for recognizing both inorganic and organic handwritten chemical expressions. Introduces the Chemical Expression Structure Graph (CESG) and uses a weighted direction graph search for structural analysis, achieving 83.1% top-5 accuracy on a large proprietary dataset.

Computational Chemistry

Probabilistic OCSR with Markov Logic Networks

This paper introduces MLOCSR, a system that pipelines low-level image vectorization with a high-level probabilistic Markov Logic Network to recognize chemical structures. It replaces brittle heuristics with weighted logic rules, significantly outperforming state-of-the-art systems like OSRA on degraded or low-resolution images.

Computational Chemistry
ChemInk: Real-Time Recognition for Chemical Drawings

ChemInk: Real-Time Recognition for Chemical Drawings

ChemInk introduces a sketch recognition system for chemical diagrams that combines multi-level visual features via a joint Conditional Random Field (CRF), achieving 97.4% accuracy and outperforming CAD tools in user speed.

Machine Learning Fundamentals
Diagram showing distributed representations with three pools of units (AGENT, RELATIONSHIP, PATIENT) connected via role/identity bindings

Distributed Representations: A Foundational Theory

Geoffrey Hinton’s seminal 1984 technical report that formally derives the efficiency of distributed representations (coarse coding) and demonstrates their properties of automatic generalization, content-addressability, and robustness to damage.

Computational Chemistry

Hand Drawn Chemical Diagram Recognition

An early method paper (AAAI ‘07) proposing a multi-stage sketch recognition pipeline. It introduces a domain verification step that uses chemical rules to refine ink parsing, achieving a 27% error reduction over geometric-only baselines.

Computational Chemistry
Optical chemical structure recognition example

IMG2SMI: Translating Molecular Structure Images to SMILES

A 2021 image-to-text approach treating OCSR as an image captioning task. It uses Transformers with SELFIES representation to convert molecular structure diagrams into SMILES strings, unlocking visual chemical knowledge from scientific literature.

Computational Social Science
Hierarchical Ideal Point Topic Model visualization showing political polarization

Tea Party in the House: Legislative Ideology via HIPTM

This paper introduces the Hierarchical Ideal Point Topic Model (HIPTM) to analyze the 112th U.S. Congress. By jointly modeling votes and text, it uncovers how Tea Party Republicans and establishment Republicans differ in both voting records and how they frame specific policy issues.

Generative Modeling
Diagram comparing standard stochastic sampling (gradient blocked) vs the reparameterization trick (gradient flows)

Auto-Encoding Variational Bayes: VAE Paper Summary

Kingma and Welling’s foundational 2013 paper introducing Variational Autoencoders and the reparameterization trick, enabling end-to-end gradient-based training of generative models with continuous latent variables by moving the stochasticity outside the computational graph so that gradients can flow through a deterministic path.

Generative Modeling
MNIST digit samples generated from a Variational Autoencoder latent space

Importance Weighted Autoencoders: Beyond the Standard VAE

Discover how Importance Weighted Autoencoders (IWAEs) use the same architecture as VAEs with a fundamentally more powerful objective to leverage multiple samples effectively.

Generative Modeling
Flowchart comparing VAE and IWAE computation showing the key difference in where averaging occurs relative to the log operation

IWAE: Importance Weighted Autoencoders

Burda et al.’s ICLR 2016 paper introducing Importance Weighted Autoencoders, which use importance sampling to derive a strictly tighter log-likelihood lower bound than standard VAEs, addressing posterior collapse and improving generative quality. The model architecture remains the same.

Computational Chemistry
Benzene in SELFIES notation

Recent Advances in the SELFIES Library (2023)

A 2023 software update paper documenting major improvements to the SELFIES Python library, including architectural redesign using directed molecular graphs for faster performance, expanded chemical feature support, semantic constraints for validity, and user-friendly customization APIs that transform SELFIES from proof-of-concept into production-ready tool.

Computational Chemistry
SELFIES molecular representation overview

SELFIES: The Original Paper (Krenn et al. 2020)

The 2020 paper that introduced SELFIES: Mario Krenn and colleagues created a molecular representation that solves SMILES validity problems. It guarantees every generated string corresponds to a valid chemical structure.