How many surveys to demonstrate absence?

In the lecture today in Environmental Monitoring and Audit, I mentioned the model examining how much search effort is required to be sufficiently sure of the absence of a species at a site. This was based on a paper by Brendan Wintle et al. (2012).

You can read more about this topic here, with an attempt at an intuitive interpretation of the model, and some links to other examples where the prior probability (base rate) matters.

If you are particularly keen, you can read a copy of the manuscript here.


Wintle, B.A. Walshe, T.V., Parris, K.M., and McCarthy, M.A. (2012). Designing occupancy surveys and interpreting non-detection when observations are imperfect. Diversity and Distributions 18: 417-424.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s