Models, Methods, Software

“The purpose of computing is insight, not numbers.” Richard Hamming

In order to gain insight, deep understanding of the source of the numbers is of paramount importance. Until deep understanding of the source of the numbers is attained, the numbers do not provide insight. In my opinion, deep understanding of the source of the numbers is best attained by a bottom-up approach. Merely comparing line, contour, or 3-dimensional plots of some calculated numbers does not constitute either understanding or verification/validation.
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Here is a start on a bibliography for V&V and SQA books and articles.
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I’ve started a summary of Web sites that I have found useful. I’ll add to it as time permits.
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I just ran across info about this new book over at Prometheus;
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I have a kind of long discussion paper on V&V and SQA that I put together a couple of years ago. I have uploaded a copy V&V and SQA.

I discovered that the spam filter had sucked in all your comments. I’ll be more careful that I clear them ASAP in the future.

Thank you for your excellent comments and I hope you’ll come back often.

I have posted several short discussions of software Verification, Validation (V&V) and Software Quality Assurance (SQA) issues a few times at several blogs. I continue to hope that more complete discussions of significant software engineering issues will follow. So far that has not happened. I have made other direct contacts too, but also without success.

Documentation of the models, methods, and software is the key focus relative to V&V and SQA . My research is conducted mainly on the Web. It is entirely possible that I have missed what I’ve been looking for. But no one has yet provided the information that I know is needed in order to provide creditability to projections/predictions from any and all computer software.

All these codes, and all other aspects of all the software used in the climate-change community, belong to us. The continued lack of open documentation is an affront to all of us who have paid for these products and their applications. The climate-change community must open the documentation windows and let some sunshine in.
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The Basic Hypotheses

The following is well known but because it is the focus of this discussion I list it for handy reference.

Convergence is Paramount; Nothing else Counts

The fundamental objective of numerical solution of systems of algebraic equations, ordinary differential equations (ODEs) and partial differential equations (PDEs) is to ensure that the approximations made in order to solve the equations do not in fact influence the solutions. In the case of systems of algebraic equations, it must be shown that the stopping criteria applied to iterative solution methods does not influence the accepted solutions. The solutions are independent, to an acceptable level, of the stopping criteria, and the calculated numbers satisfy the equations.
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