Deep-learning: investigating deep neural networks hyper-parameters and comparison of performance to shallow methods for modeling bioactivity data
By Alexios Koutsoukas, Keith J. Monaghan, Xiaoli Li, Jun Huan. 2017
271 citations recorded by the source corpus.
BackgroundIn recent years, research in artificial neural networks has resurged, now under the deep-learning umbrella, and grown extremely popular. Recently reported success of DL techniques in crowd-sourced QSAR and predictive toxicology competitions has showcased these methods as powerful tools in drug-discovery and toxicology research. The aim of this work was dual, first large number of hyper-parameter configurations were explored to investigate how they affect the performance of DNNs and could act as starting points when tuning DNNs and second their performance was compared to popular methods widely employed in the field of cheminformatics namely Naïve Bayes, k-nearest neighbor, random forest and support vector machines. Moreover, robustness of machine learning methods to different levels of artificially introduced noise was assessed. The open-source Caffe deep-learning framework and modern NVidia GPU units were utilized to carry out this study, allowing large number of DNN configurations to be explored.ResultsWe show that feed-forward deep neural networks are capable of achieving strong classification performance and outperform shallow methods across diverse activity classes when optimized. Hyper-parameters that were found to play critical role are the activation function, dropout regularization, number hidden layers and number of neurons. When compared to the rest methods, tuned DNNs were found to statistically outperform, with p value <0.01 based on Wilcoxon statistical test. DNN achieved on average MCC units of 0.149 higher than NB, 0.092 than kNN, 0.052 than SVM with linear kernel, 0.021 than RF and finally 0.009 higher than SVM with radial basis function kernel. When exploring robustness to noise, non-linear methods were found to perform well when dealing with low levels of noise, lower than or equal to 20%, however when dealing with higher levels of noise, higher than 30%, the Naïve Bayes method was found to perform well and even outperform at the highest level of noise 50% more sophisticated methods across several datasets.
Subfields: Biophysics, Computational Theory and Mathematics, Molecular Biology
How researchers see this paper
The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.
In Computational Theory and Mathematics
- Li Yang
- Abdallah Shami
- Ola Engkvist
- Valery Tkachenko
- Sean Ekins
- Yinhai Wang
- Marcus Olivecrona
- Alexandru Korotcov
In Molecular Biology
- Ola Engkvist
- Valery Tkachenko
- Li Yang
- Abdallah Shami
- Sean Ekins
- Yinhai Wang
- Marcus Olivecrona
- Alexandru Korotcov
Citations in the corpus
- On Hyperparameter Optimization of Machine Learning Algorithms: Theory and Practice (2020, background): “Since all neural network models have an input layer and an output layer, the complexity of a deep learning model mainly depends on the number of hidden layers and the number of neurons of each layer, which are two main hyper-parameters to build DL models [64].”
- A review on machine learning approaches and trends in drug discovery (2021, background): “In general the most complex part of this ML model is obtaining datasets of sufficient size and finding the best hyperparameters for drug analysis [29].”
- Comparison of Deep Learning With Multiple Machine Learning Methods and Metrics Using Diverse Drug Discovery Data Sets. (2017, methodology): “A second group has assessed several machine learning methods with 7 ChEMBL datasets but only focused on a single metric to assess performance 42 .”
- The rise of deep learning in drug discovery. (2018, methodology): “[39] compared a DNN model with some commonly used machine learning methods such as SVM, RF, among others, on seven datasets selected from ChEMBL [40].”