EstimateS Support

The EstimateS User's Guide

EstimateS support starts, and usually ends, with the EstimateS User's Guide, which hasdeliberately been written in much more detail than most manuals, to provide you with full access to the information you need.

"How To" Questions: The User's Guide is the first place to go to find out if EstimateS can do something you want done. Use the comprehensive Table of Contents or your browser's search tool to see if you can find the answer you need.

Support by Email

E-mailed questions that can be answered by consulting the EstimateS User's Guide will receive the lowest priority for email support, or may not be answered at all. Please understand that EstimateS has thousands of users, and exactly one busy professor to keep up with support email.

Technical problems with EstimateS or problems with the EstimateS Website .You may request email help with problems you can't solve with the help of the EstimateS User's Guide. Please contact EstimateS's author, Robert Colwell at

When preparing an email with a request for for support, please be sure to include the following:

  1. The word "EstimateS" in the message Subject.

  2. Version of EstimateS. From the File menu in EstimateS, select "About EstimateS." Record the Version and Date of the copy of EstimateS that you are using.

  3. Your computer's Operating System.

  4. A detailed description of what you are trying to do, or the problem you have doing it.

Please do not telephone the Author with support questions.

Bug Reporting

If EstimateS does something you did not expect, first try consulting the EstimateS User's Guide to see if the behavior is normal. If something happens that is clearly not intended, you may have found a bug. If a 4th Dimension error window appears, you have definitely found a bug.

If you believe you have discovered a bug, please email EstimateS's author, Robert Colwell at

When preparing an email with a bug report, please be sure to include the following:

  1. The word "EstimateS" in the message Subject.

  2. Version of EstimateS. From the File menu in EstimateS, select "About EstimateS." Record the Version and Date of the copy of EstimateS that you are using.

  3. Your computer's Operating System.

  4. A description of the problem. To be most useful the description of the problem should include a full account of the steps that led up to it. If at all possible, try making it happen again until you are sure what steps reliably produce the problem. If the problem cannot be reproduced, it cannot be fixed.

  5. Any data that were involved. If the problem seems to concern a particular data set, please send the input file as an attachment.

Known Bugs and Problems

  • ACE is not correctly computed for individual-based data. Chao1 is reported instead. This bug will be fixed in the next version.

Notes for Mac OS X

  • None at this time.

Notes for Windows

  • If you get a 4D "Create a New Segment" Message or "Cannot save changes to file" message. If you get a message saying you cannot save changes to file, or an offer to "Create a new segment," your system is probably set up to write-protect files.   You need to have Write privileges to use EstimateS.   See your IT administrator.

Your Suggestions for EstimateS

EstimateS's current tools and features evolved over a period of nearly 20 years, partly under the guidance of EstimateS users. Suggestions for improvement are welcomed. Please email EstimateS's author, Robert Colwell at Please include the word "EstimateS" in the Subject line of your message.

Recent Version History

New in EstimateS 9.1.0:

  • Chao1 and Chao 2 computations have now been comprehensively revised to take account of more special cases and to reduce small-sample bias. See Appendix B in the User's Guide.

  • Individual-based rarefaction is now carried out using the classic multinomial model, instead of the Poisson model, as in Version 9.0.0. Individual-based extrapolation continues to use the multinomial model.

  • For Individual-based rarefaction, a bootstrap unconditional variance estimator for special cases has been implemented (all cases in which Sest = Sobs for the reference sample), based on Appendix G of Chao et al. 2013. Similar estimators for theses cases will be implemented for Individual-based extrapolation and for sample-based rarefaction and extrapolation in a future version.

  • Bug fixed: The on-screen settings for Skip Columns and Skip Rows for Individual-based Data File input did not work.   Fixed in 9.1.0.


New in EstimateS 9.0.0:

  • A  comprehensively revised User's Guide covering all the new features in EstimtateS 9 and all the traditional ones of previous versions.

  • An entirely new capability for handing individual-based rarefaction with true (unconditional) confidence intervals (and of course, sample-based rarefaction, the core of all previous versions of EstimateS).

  • Rarefaction of richness estimators and diversity indices for individual-based data (as well as sample-based data, as in previous versions).

  • Non-parametric extrapolation of rarefaction curves for both sample-based and individual-based data (Colwell et al. 2012).

  • Batch input and export option for both sample-based and individual-based datasets.

  • Options for computing, displaying, and exporting subsets of results for evenly-spaced intervals for rarefaction and extrapolation of samples or individuals (interval-sampling or knots).

  • Automatic support for International and US number formats.

  • EstimateS 9 for Windows runs under Windows 8, Windows 7, Vista, and XP.

  • EstimateS 9 for Mac OS runs under OS 10.5 (Leopard) through 10.8 (Mountain Lion).

  • EstimateS 9 is blazing fast, compared to earlier versions.

New in EstimateS 8.2.0:

  • In the Diversity Indexes output, the exponential form of Shannon diversity ( eH) and its conditional standard deviation are reported (as well as H itself, using natural logarithms, as in previous versions).

  • Bugs fixed:
    • In Version 8.00 (but not in earlier versions), the application froze if the Diversity Indexes option was checked and one or more samples in the input dataset were completely empty (no individuals of any species).   This bug has been fixed in Version 8.20.
    • In Version 8.00 and Version 7.52, the Morisita-Horn similarity index computations experienced an untrapped overflow when input numbers were extremely large, yielding nonsensical results (including M-H values less than zero and greater than unity). This bug has been fixed in Version 8.20.
    • Under some conditions, Version 8 did not read Biota output files correctly. This bug has been fixed in Version 8.20.

New in EstimateS 8.0.0:

  • Built around a new version of 4D Engine that ensures compatibility with the latest operating systems.
  • Option to export results from n individual randomizations to a text file, allowing computation of precision, accuracy, and other analyses.
  • Improved detection and reporting on input file problems.
  • Corrected all known bugs in previous versions, including an error in confidence interval computations for Chao1 and Chao2 (with generally minor effects).


Robert K. Colwell