Skip to main content    

An official website of the United States government

Here’s how you know

**Official websites use .gov**              A **.gov** website belongs to an official government organization in the United States.            

**Secure .gov websites use HTTPS**              A **lock** (  LockA locked padlock) or **https://** means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.            

https://www.nist.gov/itl/sed/products-services/statistical-reference-data-sets-strd

            -  Topics  -  All Topics 
-  Advanced communications 
-  Artificial intelligence 
-  Bioscience 
-  Buildings and construction 
-  Chemistry 
-  Climate 
-  Cybersecurity 
-  Electronics 
-  Energy 
-  Environment 
-  Fire 
-  Forensic science 
-  Health 
-  Information technology 
-  Infrastructure 
-  Manufacturing 
-  Materials 
-  Mathematics and statistics 
-  Metrology 
-  Nanotechnology 
-  Neutron research 
-  Performance excellence 
-  Physics 
-  Public safety 
-  Resilience 
-  Standards 
-  Transportation 
 
            -  Publications 
            -  Labs & Major Programs  -  Laboratories    -  Communications Technology Laboratory 
  -  Engineering Laboratory 
  -  Information Technology Laboratory 
  -  Material Measurement Laboratory 
  -  Physical Measurement Laboratory 
-  User Facilities    -  NIST Center for Neutron Research 
  -  CNST NanoFab 
-  Research Test Beds 
-  Research Projects 
-  Tools & Instruments 
-  Major Programs    -  Baldrige Performance Excellence Program 
  -  CHIPS for America Initiative 
  -  Manufacturing Extension Partnership (MEP) 
  -  Office of Advanced Manufacturing 
  -  Special Programs Office 
  -  Technology Partnerships Office 
 
            -  Services & Resources  -  Standards and Measurements    -  Calibration Services 
  -  Laboratory Accreditation (NVLAP) 
  -  Quality System 
  -  Standard Reference Materials (SRMs) 
  -  Standards.gov 
  -  Time Services 
  -  Office of Weights and Measures 
-  Software 
-  Data    -  Chemistry WebBook 
  -  National Vulnerability Database 
  -  Physical Reference Data 
  -  Standard Reference Data (SRD) 
-  Storefront 
-  License & Patents 
-  Computer Security Resource Center (CSRC) 
-  NIST Research Library 
 
            -  News & Events  -  News 
-  Events 
-  Blogs 
-  Feature Stories 
-  Awards 
-  Video Gallery 
-  Image Gallery 
-  Media Contacts 
 
            -  About NIST  -  About Us    -  Leadership 
  -  Organization Structure 
  -  Budget & Planning 
-  Contact Us 
-  Visit 
-  Careers    -  Student programs 
-  Work with NIST 
-  History    -  NIST Digital Archives 
  -  NIST Museum 
  -  NIST and the Nobel 
-  Educational Resources 
 

Information Technology Laboratory

## Statistical Engineering Division

-  Projects/Programs  Expand or Collapse    -  Cement Characteristics by Direct Phase Assessment 
  -  Critical Current Metrology for Nb3Sn 
  -  e-Statistics 
  -  Extreme Winds and Wind Effects on Structures 
  -  Radiative Decay of the Neutron 
-  How to Work With Us 
-  NIST Publications Searchable Database 
-  Staff Directory 
-  Topic Areas  Expand or Collapse    -  e-Handbook 
  -  Measurement Uncertainty 
  -  NRC Postdoctoral Associate Program 
  -  SED Consulting Program 
  -  Statistical Methods 
  -  Teaching 
  -  Other Statistics Information 
-  Products & Services  Expand or Collapse    -  e-Handbook 
  -  Statistical Metrology Short Courses 
  -  Statistical Reference Data Sets (StRD) 
  -  Statistical Software 
  -  Test Suite for Random Numbers 
-  Historical Information 

# Statistical Reference Datasets (StRD)

## Share

Facebook

Linkedin

Twitter

Email

## Summary:

The Statistical Reference Datasets (StRD) provides a Web-based service that provides reference datasets with certified values for a variety of statistical methods.

## Description:

With the widespread use and availability of statistical software, concerns about the numerical accuracy of such software are now greater than ever. Inevitably, numerical accuracy problems can exist with some of this software despite extensive testing. Indeed, this has been a continuing cause of concern for statisticians. Many have cited the need for an easily-accessible repository of reference datasets. To date no such collection has been available. In response to concerns of both the statistical community and industrial users, the Statistical Engineering Division in collaboration with the Mathematical & Computational Sciences Division and Standard Reference Data Program have developed a Web-based service that provides reference datasets with certified values for a variety of statistical methods. This service is called Statistical Reference Datasets (StRD).

Currently 58 datasets with certified values are provided for assessing the accuracy of software for univariate statistics, analysis of variance, linear regression, and nonlinear regression. The collection includes both generated and "real-world" data of varying levels of difficulty. Generated datasets are designed to challenge specific computations. These include the classic Wampler datasets for testing linear regression algorithms and the Simon & Lesage datasets for testing analysis of variance algorithms. Real-world data include challenging datasets such as the Longley data for linear regression, and more benign datasets such as the Daniel & Wood data for nonlinear regression.

Certified results for linear procedures were obtained using extended precision software to code simple algorithms for each type of computation. Carrying 500 digits through all of the computations allowed calculation of output unaffected by floating point representation errors. Certified values for nonlinear regression are the "best-available" solutions, obtained using 64-bit precision and confirmed by at least two different algorithms and software packages using analytic derivatives.

The team officially released the StRD web service in August 1997 and spent the latter part of that year publicizing the web service. A special contributed paper session was presented at the 1997 Joint Statistical Meetings in August. Talks were also given at NIST Gaithersburg and Boulder.

With the increased usage of Bayesian methods, the StRD web site was updated with six more data sets in 2003 to provide reference datasets for Markov Chain Monte Carlo. The certified values for these datasets were obtained by adopting a model for which closed form solutions are known and computing the numeric values of those theoretical solutions using extended precision software.

## Major Accomplishments:

L.M. Gill, Navigating Through the Statistical Reference Dataset (StRD) Website, Shaping Statistics for Success in the 21st Century, Joint Statistical Meetings '97, Anaheim, CA, August 11, 1997.

E.S. Lagergren, Statistical Reference Datasets (StRD) - An Overview, Joint Statistical Meetings, Anaheim, CA, August 11, 1997.

Initial public release August, 1999.

W.F. Guthrie, J.E. Rogers, J.J. Filliben, L.M. Gill, E. Lagergren, M.G. Vangel, Statistical Reference Datasets (StRD) for Assessing the Numerical Accuracy of Statistical Software, 31st Symposium on the Interface: Models, Predictions, and Computing, Schaumburg, IL, June 10, 1999.

W.F. Guthrie, H.-K. Liu, D. Malec, G. Yang, MCMC in StRD, NCSLI, Salt Lake City, UT, July 2004.

H.-K. Liu, W.F. Guthrie, D. Malec, G. Yang, An Update on StRD for MCMC, Joint Statistical Meetings, Toronto, ON, Canada, August 2004.

W.F. Guthrie, H.-K. Liu, D. Malec, G. Yang, Ranking the Sources of Numerical Error in MCMC Computations, Joint Statistical Meetings, Toronto, ON, Canada, August 2004.

H.-K. Liu, W.F. Guthrie, D. Malec, G. Yang, An Update on the NIST Statistical Reference Datasets for MCMC: Ranking the Sources of Numerical Error in MCMC Computations, Washington Statistical Society, Washington, DC, June 2006.

**Former NIST Staff:**

Carroll Croarkin, Lisa Gill, Eric Lagergren, Don Malec, Mark Vangel

Data and informaticsMathematics and statisticsStatistical analysis

## Contacts

### Contact

                -  William F Guthrie  william.guthrie@nist.gov      (301) 975-2854   
                -  Hung-Kung Liu  hung-kung.liu@nist.gov      (301) 975-2718   

### Staff

                -  William F Guthrie  william.guthrie@nist.gov      (301) 975-2854   
                -  Hung-Kung Liu  hung-kung.liu@nist.gov      (301) 975-2718   

                -  Fan Zhang  fan.zhang@nist.gov      (301) 975-5734   

### HEADQUARTERS

301-975-2000

Webmaster | Contact Us | Our Other Offices

TwitterFacebookLinkedInInstagramYouTubeGiphyRSS FeedMailing List

Feedback

            -  Site Privacy 
            -  Accessibility 
            -  Privacy Program 
            -  Copyrights 
            -  Vulnerability Disclosure 
            -  No Fear Act Policy 
            -  FOIA 
            -  Environmental Policy 
            -  Scientific Integrity 
            -  Information Quality Standards 
            -  Commerce.gov 
            -  Science.gov 
            -  USA.gov 
            -  Vote.gov