> For the complete documentation index, see [llms.txt](https://time-series-features.gitbook.io/pyspi/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://time-series-features.gitbook.io/pyspi/information-about-pyspi/spis/spi-descriptions.md). # SPI Descriptions Descriptions of each method. {% hint style="info" %} The documentation accompanying the toolkit, including the tables and descriptions of each SPI, represent the features and functionality of the original pyspi library as detailed in the [Supplementary Material ](https://www.readcube.com/articles/supplement?doi=10.1038%2Fs43588-023-00519-x\&index=0)of the original *pyspi* paper. While we strive to keep our documentation as current and comprehensive as possible, our library of SPIs may undergo frequent updates and enhancements to align with the latest advancements and user feedback. {% endhint %} ## Basic Statistics


	Covariance		Basic Statistics
	Cross Correlation		Basic Statistics
	Kendall's Rank Correlation Coefficient		Basic Statistics
	Precision		Basic Statistics
	Spearman's Rank Correlation Coefficient		Basic Statistics

*** ## Distance Similarity


	Barycenter		Distance Similarity
	Cross Distance Correlation		Distance Similarity
	Cross Multiscale Graph Correlation		Distance Similarity
	Distance Correlation		Distance Similarity
	Dynamic Time Warping		Distance Similarity
	Gromov-Wasserstein Distance		Distance Similarity
	Heller-Heller-Gorfine Independence Criterion		Distance Similarity
	Hilbert-Schmidt Independence Criterion		Distance Similarity
	Longest Common Subsequence		Distance Similarity
	Multiscale Graph Correlation		Distance Similarity
	Pairwise Distance		Distance Similarity
	Soft Dynamic Time Warping		Distance Similarity

*** ## Causal Inference


	Additive Noise Model		Causal Inference
	Conditional Distribution Similarity Fit		Causal Inference
	Convergent Cross-Mapping		Causal Inference
	Information-Geometric Causal Inference		Causal Inference
	Regression Error-Based Causal Inference		Causal Inference

*** ## Information Theory


	Causally Conditioned Entropy		Information Theory
	Conditional Entropy		Information Theory
	Directed Information		Information Theory
	Granger Causality		Information Theory
	Integrated Information		Information Theory
	Joint Entropy		Information Theory
	Mutual Information		Information Theory
	Stochastic Interaction		Information Theory
	Transfer Entropy		Information Theory
	Time-lagged Mutual Information		Information Theory

*** ## Spectral


	Coherence Magnitude		Spectral
	Coherence Phase		Spectral
	Directed Coherence		Spectral
	Directed Transfer Function		Spectral
	Group Delay		Spectral
	Imaginary Coherence		Spectral
	Pairwise Phase Consistency		Spectral
	Partial Directed Coherence		Spectral
	Phase Lag Index		Spectral
	Phase Locking Value		Spectral
	Phase Slope Index		Spectral
	Spectral Granger Causality		Spectral

*** ## Miscellaneous


	Cointegration		Miscellaneous
	Gaussian Process Model Fit		Miscellaneous
	Linear Model Fit		Miscellaneous
	Power Envelope Correlation		Miscellaneous

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