Automatic Selection of t-SNE Perplexity

Yanshuai Cao; Luyu Wang

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arXiv · 1708.03229

Automatic Selection of t-SNE Perplexity

Yanshuai Cao·Luyu Wang

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Abstract

t-Distributed Stochastic Neighbor Embedding (t-SNE) is one of the most widely used dimensionality reduction methods for data visualization, but it has a perplexity hyperparameter that requires manual selection. In practice, proper tuning of t-SNE perplexity requires users to understand the inner working of the method as well as to have hands-on experience. We propose a model selection objective for t-SNE perplexity that requires negligible extra computation beyond that of the t-SNE itself. We empirically validate that the perplexity settings found by our approach are consistent with preferences elicited from human experts across a number of datasets. The similarities of our approach to Bayesian information criteria (BIC) and minimum description length (MDL) are also analyzed.

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BibTeX RIS

Yanshuai Cao, Luyu Wang. 2017-08-10. Automatic Selection of t-SNE Perplexity. https://arxiv.org/abs/1708.03229

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