Your average scripter likely isn't writing a whole lot of proofs or going through the rigors of formal program verification, generally. Which is fine because your average scripter also isn't writing software for jet airliners or nuclear power plants or robotic surgeons. But somebody is—and the odds are pretty good that your life has been in their hands very recently. How do you know they're not a complete hack ?
Well, you don't really. Which prompts the question: How is this sort of code tested? It was a short blog post written by Gene Spafford, a professor of computer science at Purdue University, that inspired this particular asking of the question.
http://motherboard.vice.com/read/how-is-critical-life-or-death-software-tested
[Related]: They Write the Right Stuff by Charles Fishman at Fast Company
(Score: 0) by Anonymous Coward on Thursday June 04 2015, @12:27AM
No idea what the pacemaker does exactly. But I bet it is partly statistical (is the beat outside an expected range?). I learned my lesson by independently coming across this issue:
http://stats.stackexchange.com/questions/18854/issues-with-the-huynh-feldt-values-using-either-anova-or-ezanova-in-r [stackexchange.com]
The advantage of open vs closed source is not really the bugs, rather that it is in the vested interest of the vendor in not acknowledging them. In this case people getting false positive stats outputs for ~30 years after it should have been known.