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Old 04-25-2008, 09:13 AM
alextsakiris alextsakiris is offline
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Originally Posted by davidsmith73 View Post
I expect scientists to apply their skills and knowledge to find out what is really going on. In the case of Jaytee, I don't think Wiseman et al. did a very good job of this. Although I'll give them the benefit of the doubt and suggest they ran out of time and resources...




But it's entirely possible, and probable, that any predictive power such as this would be masked in an analysis where trials are classed as a failure because the dog goes to the waiting area for a few moments during the non-return period. Sheldrake may well have been looking at the temporal precision of this effect, but he was wise not to adopt Wiseman et al's criteria of 'hit' and 'miss' because that just massively increases your chances of type II errors for reasons I outlined before.



In the case of Sheldrake, I'm sure he was aware of these issues before he ran his experiments, so these "excuses" are not likely to be post-hoc. If you're talking about post-hoc in the sense of explaining why Wiseman et al's data didn't show an effect, I would call it "criticism" rather than "excuses".

The best way would be not to exclude any data due to distractions because you run into huge difficulties deciding what is a distraction and what is not. The best way would be to analyse the data in such away that noise causd by distractions are kept to a minimum.



I'm suggesting a way to analyse the data using the amount of time in the waiting area as the dependent variable. If you simply calculate the proportion of time spent in the waiting area during return and non-return periods then will get the artifact you were talking about. If we consider the dog behaviour in our 100 min trial example we've been using, this would result in 100% waiting time during the return period and 90% for the non-period. I am suggesting that the waiting time is calculated as a proportion of the total time in the waiting area across return and non-return periods. This would give 10% for the return period and 90% for the non-return period (ie., 100 min of waiting in the waiting spot, 90min during non-return but only 10min during the return period). This would guard against the artifact you were talking about, I think.



No, it's not imperative at all. Not many behavioural experiments measuring a continuous variable would adopt a 'hit' and 'miss' approach. It's more sensible to compare means of the dependent variable between conditions.



Now, that I may have to agree with you on. But I'm sure it will on JREF's insistence.
This is all very interesting... a couple additional points:

- This kind of analysis of the DogsThatKnow data will be done by experts trained in animal behavior research. I'm sure they have a large body of knowledge/experience (I don't regularly read Anthrozoös )

- At the same time, I plan to make their methods and techniques transparent and open for all of us to see and comment on.

- Finally, results like those achieved in the first two videos don't require a lot of advanced statistics to measure success -- it's OBVIOUS! The only question is repeatability.

Last edited by alextsakiris; 04-25-2008 at 11:22 AM..
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