Licences, credits and trademarks
FreeStatisticalTools.com, including PLS-SEM Studio and CB-SEM Studio, is written by Bibin Xavier. Its statistical code, text and design are original. It relies on the open-source components below, used under their licences, and on statistical methods from the published literature, which are cited on each tool page.
Software libraries
- jStat 1.9.6: statistical distributions. MIT License, Copyright (c) 2013 jStat. github.com/jstat/jstat
- Chart.js 4.4.1: charts. MIT License, Copyright (c) 2014-2022 Chart.js Contributors. chartjs.org
- SheetJS Community Edition 0.18.5: reading and writing Excel files. Apache License 2.0, Copyright (C) 2012-present SheetJS LLC. sheetjs.com
- JSZip 3.10.1: creating ZIP and Word files. MIT License (dual-licensed MIT or GPLv3), Copyright (c) 2009-2016 Stuart Knightley, David Duponchel, Franz Buchinger, António Afonso; includes pako (MIT and zlib licences). stuk.github.io/jszip
The MIT License permits use, copying, modification and distribution provided the copyright notice and permission notice are kept; the library files served by this site keep their original notices. The Apache License 2.0 text is available at apache.org/licenses/LICENSE-2.0.
Fonts
Geist and Geist Mono (Vercel) and Lexend are used under the SIL Open Font License 1.1 and served by Google Fonts.
Critical value tables
The unit-root and cointegration tests use the response-surface coefficients of MacKinnon (1994, 2010), as tabulated in the statsmodels project. statsmodels is distributed under the BSD 3-Clause License: Copyright (C) 2006, Jonathan E. Taylor; Copyright (c) 2006-2008 Scipy Developers; Copyright (c) 2009-2018 statsmodels Developers. All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: (a) redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer; (b) redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution; (c) neither the name of statsmodels nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DAMAGES ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE.
Statistical methods
Statistical methods themselves are not protected by copyright; each tool implements published methods independently and cites the original authors in its notes and references. Results are checked against reference software such as R’s lavaan and Python’s SciPy, statsmodels, linearmodels and pingouin; no code from those packages is included apart from the table credited above.
Trademarks
IBM SPSS Statistics and IBM SPSS Amos are trademarks of International Business Machines Corporation. Stata is a trademark of StataCorp LLC. Microsoft Excel and Word are trademarks of Microsoft Corporation. SmartPLS is a trademark of SmartPLS GmbH. PROCESS is a macro written by Andrew F. Hayes. All other product and company names mentioned on this site, such as JASP, GraphPad Prism, OpenRefine, Qualtrics, VWO and Optimizely, are trademarks or names of their respective owners. They are mentioned only to identify those products and to describe or compare functionality. FreeStatisticalTools.com is independent and is not affiliated with, sponsored by or endorsed by any of these companies or authors.