tie diagrams

Hi everybody,
can anyone help me in finding informations about tie
diagrams?
(And how to get such graphics with R).
Thanks

Hi Alessandro,

There are several sites with definitions and illustrations of "bow tie 
diagrams", e.g.

http://www.eagle.org/news/pubs/surveyor/dec99/ism.htm

It wouldn't be too hard to put something together in R to do simple ones 
with risk factors on the left and events on the right, but I suspect 
that the more complex varieties with barriers and recovery actions are 
built up box by box using a pointing device with dedicated software like 
BowTieXP. Obviously a "presentation" tool.

Jim