We visualize the standard deviation of a data set as the size of a prism whose volume equals the total volume of several prisms made from the Empirical Cumulative Distribution Function.

The sdrt() function is designed for estimating subspaces for Sufficient Dimension Reduction (SDR) in time series, with a specific focus on the Time Series Central Mean subspace (TS-CMS). The package employs the Fourier transformation method proposed by Samadi and De Alwis (2023) <doi:10.48550/arXiv.2312.02110> and the Nadaraya-Watson kernel smoother method proposed by Park et al. (2009) <doi:10.1198/jcgs.2009.08076> for estimating the TS-CMS. The package provides tools for estimating distances between subspaces and includes functions for selecting model parameters using the Fourier transformation method.

Wrapping and supplementing commonly used functions in the R ecosystem related to spatial data science, 
             while serving as a basis for other packages maintained by Wenbo Lv.

Companion package that supports the 'surveydown' survey platform (<https://surveydown.org>). The default method for working with a 'surveydown' survey is to edit the plain text 'survey.qmd' and 'app.R' files. With 'sdstudio', you can create, preview and manage surveys with a 'shiny' application as a graphical user interface.

Functions for self-determination motivation theory (SDT) to compute
    measures of motivation internalization, motivation simplex structure, and of
    the original and adjusted self-determination or relative autonomy index. SDT
    was introduced by Deci and Ryan (1985) <doi:10.1007/978-1-4899-2271-7>. See
    package?SDT for an overview.

A series of checks to identify common issues in Study Data Tabulation Model (SDTM) datasets. These checks are intended to be generalizable, actionable, and meaningful for analysis.

An Electronic Data Capture system (EDC) and Data Standard agnostic 
    solution that enables the pharmaceutical programming community to develop 
    Clinical Data Interchange Standards Consortium (CDISC)
    Study Data Tabulation Model (SDTM) datasets in R. The reusable algorithms 
    concept in 'sdtm.oak' provides a framework for modular programming and can 
    potentially automate the conversion of raw clinical data to SDTM through 
    standardized SDTM specifications. SDTM is one of the required standards for data 
    submission to the Food and Drug Administration (FDA) in the United States and 
    Pharmaceuticals and Medical Devices Agency (PMDA) in Japan. SDTM standards 
    are implemented following the SDTM Implementation Guide as defined by 
    CDISC <https://www.cdisc.org/standards/foundational/sdtmig>.