Raman spectroscopy has been evaluated for skin cancer detection. Data augmentation has been used for image processing by deep neural networks. In this study, we proposed and evaluated different data augmentation strategies for spectral augmentation, including added random noise, spectral shift, spectral combination and artificially synthesized spectra using one-dimensional generative adversarial networks (1D-GAN). The stratified samples (n=731) were divided randomly into training (70%), validation (10%) and test dataset (20%), and were repeated 56 times in parallel computing. It was found that data augmentation is not only applicable to deep neural networks, but also applicable to conventional machine learning techniques. When all the strategies were combined to augment the training dataset, the performance of the test dataset could be improved by 2-71%.
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