[SystemSafety] Qualifying SW as "proven in use"

[Derek M Jones]

Peter,

> There seems to be a general feeling that qualifying SW statistically via
> the approach given by the exponential failure model is not practical,
> because the data requirements are overwhelming - it is regarded by most
> as implausible that companies will have the requisite data to the
> requisite quality even for SIL 2. But even if you qualify your SW for

No data no SIL 2 qualification.

Software engineering has a culture of not measuring and keeping data.
This is starting to change, but empirical software engineering has
only just started:
http://shape-of-code.coding-guidelines.com/2011/03/31/empirical-software-engineering-is-five-years-old/

I am currently writing a book on empirical software engineering
and with some effort have often been able to find one instance
of a data set covering a topic of interest (yes, one, not
two or three or more; it is also surprising how often I email
researchers for their data from papers published a few years
ago and they no longer have it):
http://shape-of-code.coding-guidelines.com/2012/06/22/background-to-my-book-project-empirical-software-engineering-with-r/

What we also need are experiments involving the people who
write software, this is even thinner on the ground.
My own experimental work + and data here:
www.knosof.co.uk/dev-experiment.html

If anybody knows of any interesting datasets do please let me know.
I am making all data+my analysis code public and so have no interest
in data I cannot freely share.

-- 
Derek M. Jones                  tel: +44 (0) 1252 520 667
Knowledge Software Ltd          blog:shape-of-code.coding-guidelines.com
Software analysis               http://www.knosof.co.uk