Changes in version 1.1.9 (2026-04-30) - Added a new groups argument to sobol_matrices() and sobol_indices() that allows the user to compute Sobol' first-, total- and higher-order indices for groups of parameters rather than for individual parameters. This is the standard device used in Sobol'-based sensitivity analysis to handle correlated inputs by moving them together. groups accepts either a named list of character vectors of parameter names (e.g. groups = list(g1 = "X1", g2 = c("X2", "X3"))) or a character vector of length length(params) aligned with params. The grouping must be a strict partition of params (each parameter appears in exactly one group). When groups = NULL (the default), behaviour is unchanged. The order argument is reinterpreted as interactions between groups when groups is supplied. - Added test coverage for the new grouped design in both sobol_matrices() and sobol_indices(), including row-count, column-swap, list/vector equivalence, trivial-partition regression, and validation error paths. Changes in version 1.1.8 (2026-04-05) - Fixed repeated set.seed() calls in metafunction(): the seed is now set once at the beginning of the function, allowing the RNG to advance naturally across all subsequent sample() and rnorm() calls. - Added #' @keywords internal / #' @noRd roxygen2 blocks to all undocumented internal helpers: sobol_dummy_boot(), sobol_boot(), bootstats(), sobol_sample(), plot_sobol_convergence(), add_ribbon(), theme_AP(), CutBySize(), s_ersatz(), and ishigami(). - Updated the package-level documentation in sensobol-package.R to correctly state support for up to fourth-order (not third-order) Sobol' indices. - Expanded the @return documentation of sobol_convergence() to enumerate all list elements returned, including their types and column names. - Fixed multi-line string in stop() call in sobol_convergence() by replacing the embedded newline with paste(). - Extended test coverage to include: second and third-order indices, sobol_convergence() workflow and error paths, vars_matrices() / vars_to(), discrepancy_ersatz(), metafunction() reproducibility, and plot.sensobol(). Changes in version 1.1.7 - Fixed boolean logic errors in sobol_boot(): replaced !x == "value" chains with %in% to correctly validate estimator names for all matrix configurations. - Added early anyNA() guard in sobol_indices() and sobol_dummy() to stop with an informative error when Y contains NA or NaN values. - Added input validation in sobol_matrices() (N must be a positive integer), sobol_convergence() (sub.sample must be non-empty, positive, and sorted), and vars_matrices() (star.centers must be a positive integer). - Replaced auto-installing behaviour in load_packages(): the function no longer calls install.packages() silently; it now stops with an informative message directing the user to install the missing package themselves. - Replaced deprecated expect_is() with expect_true(is.matrix()) in the test suite. - Expanded test coverage to include the core sobol_indices() workflow, bootstrap output, all new validation error paths, sobol_dummy(), and the benchmark test functions ishigami_Fun() and sobol_Fun(). Changes in version 1.1.6 (2025-07-24) - Added missing package anchors. Changes in version 1.1.5 (2024-02-21) - Added the journal citation for the "discrepancy_ersatz" function. It is published in A. Puy, P. T. Roy and A. Saltelli. 2024. "Discrepancy measures for global sensitivity analysis". Technometrics. DOI: 10.1080/00401706.2024.2304341. Changes in version 1.1.4 (2023-04-06) - Added the function "discrepancy_ersatz" to use the S-ersatz discrepancy as a sensitivity measure. The S-ersatz is published in A. Puy, P. Roy and A. Saltelli. 2023. Discrepancy measures for sensitivity analysis. arXiv: 2206.13470). Changes in version 1.1.3 (2022-11-25) - Added the function "load_packages" to load (and install in case they are not already in the local R setup) all required libraries in just one call. Changes in version 1.1.2 (2022-11-16) - Fixed a bug on sobol_matrices that caused the function to fail when a single parameter was passed into the "params" argument. - Added a line in the help page of the sobol_indices and sobol_dummy functions informing that the Y argument does not accept NA or NaN values in the model output. Changes in version 1.1.1 (2022-04-26) - The CITATION file has changed. Citations to sensobol should now refer to the paper published in the Journal of Statistical Software: Arnald Puy, Samuele Lo Piano, Andrea Saltelli, and Simon A. Levin. sensobol: an R package to compute variance-based sensitivity indices. Journal of Statistical Software 102.5 (2022), pp. 1-37. doi: 10.18637/jss.v102.i05 - The metafunction has been extended with a piecewise large, piecewise small and an oscillation function. Changes in version 1.1.0 (2021-12-09) - The package now includes support to calculate and plot up to fourth-order effects. Changes in version 1.0.4 - Fixed redundant links in the bibliography in .Rd files. Changes in version 1.0.3 (2021-07-24) - Added a help page for the package. - Corrected a bug in sobol_ode. Changes in version 1.0.2 (2021-05-30) - The function plot_sensobolhas been eliminated. Now the Sobol' indices can be plot by a single call to plot. - Third-order indices are now referred to as Sijl rather than Sijk. - The function sobol_convergencehas been added to check the convergence of Sobol' indices across sub-samples of the model output. Changes in version 1.0.1 (2021-04-08) - The output of sobol_indices is now an object of class sensobol. Besides including the indices, it also informs on the sum of first-order effects, the estimators used in the computation and the total number of model runs. - The output of vars_to is now an object of class vars. Besides including the indices, it also informs on the number of stars and the h value used. - The function plot_sobol is deprecated and will be removed from future versions. Now the output of sobol_indicescan be printed with a call to plot. Changes in version 1.0.0 (2021-01-26) - This is a major package upgrade. - The package now includes four first-order (Sobol', Salteli, Jansen and Azzini) and eight total-order (Jansen, Sobol', Homma, Saltelli, Janon, Glen, Azzini and VARS-TO) sensitivity estimators. - The sample matrix can be constructed either with Sobol' quasi-random numbers, a latin hypercube design or random numbers. - Several functions to plot the results of the uncertainty and sensitivity analysis have been incorporated: the function plot_scatter plots the model inputs against the output, whereas the function plot_multiscatter plots x_i against x_j and maps the resulting coordinate to its respective model output value. - The package can now be used in models with either a scalar or a multivariate output. Changes in version 0.2.2 (2020-02-25) - This release prepares the users for a major upcoming improvement of the package. - Added warnings to the function sobol_matrices. The arguments n and k will be substituted by N and params in the next release of the package. The arguments second and third will be substituted by the argument order in the next release of the package. - Added warnings to the functions plot_uncertainty, plot_scatter, sobol_dummy and sobol_indices. The argument n will be substituted by N in the next release of the package. - The function sobol_ci is deprecated. The computation of confidence intervals will be done directly by sobol_indices in the next version of the package. - The function sobol_ci_dummy is deprecated. The computation of confidence intervals for dummy parameters will be done directly by sobol_dummy in the next version of the package. - The function sobol_replicas is deprecated and will be removed in the next version of the package. - The test function ishigami_Mapply would be renamed as ishigami_Fun in the next release of the package. Changes in version 0.2.1 (2019-09-20) - Corrected a bug in the plot_uncertainty function. Now the function demands to add the initial sample size n to visualize the model output uncertainty. - Corrected some functions to adapt them to data.table 1.12.4. - Added a new function (sobol_replicas) to easily extract the bootstrapped Sobol' indices. Changes in version 0.2.0 (2019-04-30) - New option in the sobol_matrices function: the option cluster allows to create Sobol' matrices for clusters of parameters. - New test functions added: - Bratley & Fox 1988. - Bratley et al. 1992 - Oakley & O'Hagan 2004 - Added references to all test functions. Changes in version 0.1.1 (2019-03-12) - The vignette rendered wrongly in the previous version; now the issue is corrected. - Corrected the following note, found in the CRAN check: - Namespace in Imports field not imported from: ‘parallel’. - Some functions that were exported to the R package manual are now internal. Changes in version 0.1.0 (2019-03-06) - Added a NEWS.md file to track changes to the package.