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Trigger activities

2 replies [Last post]
Alexandre Faulx-B...
User offline. Last seen 1 year 32 weeks ago. Offline
Joined: 20 Jan 2003
Posts: 1355

hello Planners,

I would like to understand how to use trigger activities, but I cannot find anything about it in the Help pages nor in the User Manual available on the web site

Can anybody (Raphael?) help?

Thank you,




trigger activities are used for MC simulation.

Actually trigger represents some risk event and if it happens the project may go different ways, each way with certain probability.

When MC simulation is applied it simulates different ways of project execution.

So in Spider Project trigger activity has zero duration and certain probability to happen.

Then you may define several trigger states each state has some probability and outcoming dependency.

For deterministic scheduling trigger position may be manually set and triggers become similar to switches.

Switch is an activity with Yes/No position. If Yes one path is selected, if No - another. Switch position may depend on some condition like if the switch happens later than certain date the project will be executed different way (different technology, additional resources, different calendars, etc.).

Triggers are useful for creating system dynamics models and simulate loops that may happen with some probability.

I will send to you small example of using triggers for simulating loops and runnung MC simulation it is possible to estimate probability of different results.