[SystemSafety] Post Office Horizon System

[Derek M Jones]

Peter,

>>> The PO used some very dodgy statistical arguments to support their
>>> reliability claim
>>> - rebutted in:
>>>
>>> https://ials.blogs.sas.ac.uk/2019/06/26/the-use-of-statistics-and-software-code/
>>>
>>
>> I think that both sides got it wrong:
>> http://shape-of-code.coding-guidelines.com/2021/01/07/likelihood-of-a-fault-experience-when-using-the-horizon-it-system/
>>
>>
> In what way did the other side get wrong?

They both assumed there was enough information available to calculate
the likelihood of a fault being experienced.

> Most of the material submitted identified fallacies in the PO
> statistical arguments
> (including the lottery analogy that you included the Shape of Code
> document).

This argument does not appear in the links you gave or the Ladkin et al
papers.  Do you have a reference?

-- 
Derek M. Jones           Evidence-based software engineering
tel: +44 (0)1252 520667  blog:shape-of-code.coding-guidelines.com