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Frequently Asked Questions


FAQs will periodically be added to the pages for each software package below. Answers to the FAQs may or may not be provided (!) and users are encouraged to submit both proposed FAQs and answers via the forms on the pages. Submitted FAQs may or may not be included, at the sole discretion of the website manager. Please ask questions about the use of the software tools only, not about modeling in general or conservation issues.


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Here is the most recently submitted FAQ:

Q:>  Hello! I have a question about mean growth rate (rs)in Vortex. I ran a model (1000 iterations over 100 years). My N vs Yr data and graph suggest a positive growth rate. However, the rs value provided by Vortex is negative (-0.01). I hand calculated the r from the N vs Yr data, and got a different (positive) value. Is there a reason the rs would be different/possibly incorrect? I only caught this because of the obvious difference in the positive graph and negative rs value. This also occurs in models run over 10 and 20 years. Has anyone else gotten different rs values than Vortex provides? Thank you for any suggestions or help!

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