by Robert Bradley » Thu Jul 10, 2008 7:08 am
The categories are being added to all the time; at last count I think there were over forty.
Many, of course, are out of the remit of the type of search we tend to be used for but with data being collected from all around the world that is understandable.
Anyone really interested should contact Bob Koester - who should be a lot freer now he has finished his latest book on the subject!
With regard to simplicity etc.
The more simplified a model becomes, generally the less relevant it is and less useful for predicting behaviour.
This doesn't mean, of course, that the interface needs to be complicated - but that the underlying data must, by its very nature be rather more complex to be useful.
If I was designing such a system, as it started collecting data, these "most popular" types of incident would populate the first drop-down box or whatever, with a link to a section with all the rest of the categories. This way you are not degrading the usefulness of the data, in order to ensure an ease of use.
Robert - if you do have sets of data on this subject I'd love to see them, even if they seem that they are not comparable; You can still learn quite a lot from them.
You are right that the UK geography makes it different to say the US, where Syrotuck did his studies, which makes it doubly important that the UK and teams collect statistics of their own. However, the UK stats we have at the moment show that search could be improved with greater knowledge of these. For example, the distances generally travelled by despondents is very low once they are on foot, even in quite rural areas. Search managers, having searched the near-by areas, tend to expand their search areas too quickly, rather than re-search these high probability areas, which would be suggested if they had seen the probability density maps these statistics produce. (Of course, trying to remember Syrotuck off the top of my head, this is one of the issues with his work in that he suggested working at different points - mean or median? something like that, rather than calculating the probability density which would be far more useful - although with a maritime search background this will be all to familiar to you.)
Robin - if I remember rightly the UK stats collected by the centre for search research are forwarded for use in the ISRID - however, the definitions given online whilst useful are not the ones used by ISRID. Bob Koester would be able to give you a lot more information and is very approachable.
As an aside, Charles Twardy, who commented on your blog, produces some great wire diagrams of probability density - something that would be very useful for managing searches.