4 ms·

Maybe you should have started with that, rather than anecdotal evidence. I agree as a case study of potential p-hacking, it's pretty illustrative. Not sure if

Maybe you should have started with that, rather than anecdotal evidence. I agree as a case study of potential p-hacking, it's pretty illustrative. Not sure if it's failed p-hacking though. For example - High school students, but did make it into a journal .. Dogs excreted with the body aligned along the North–South axis, but when exposed to small bar magnets, significantly changed their directional positions. The study suggests that dogs are able to recognize MF. Additional value of this research is that the data were collected by local high school students, which required collaboration with teachers and their parents. We think that this idea has great potential and can be developed at a global scale and to become a citizen-science project involving other high school pupils and their families. https://www.sciencedirect.com/science/article/abs/pii/S1558787819300978?via%3Dihub https://www.sciencedirect.com/science/article/abs/pii/S15587... Dogs can be trained to find a bar magnet https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6301327/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6301327/ We excluded visual cues and used control trials with food treats to test for the role of olfaction in finding the magnet. While 13 out of 16 dogs detected the magnet significantly above chance level (53–73% success rate), none of the dogs managed to do so in finding the food treat (23–40% success rate). In a replication of the experiment under strictly blinded conditions five out of six dogs detected the magnet above chance level (53–63% success rate). These experiments support the existence of a magnetic sense in domestic dogs. Whether the sense enables dogs to perceive MFs as weak as the Earth’s MF, if they use it for orientation, and by which mechanism the fields are perceived remain open questions. So maybe there is some value in p-hacking, when taken with an appropriate grain of salt? The problem is science journalism and its readers often don't know how to do that.

nate_meurer 7y ago
> Maybe you should have started with that, rather than anecdotal evidence. Oh dear. You mean I didn't approach this topic with the care it deserved? > High school students... Good for them! I only glanced at it, but it looks interesting. > Dogs can be trained to find a bar magnet... I read this. Right away, I can tell you the authors didn't take nearly enough care to eliminate the dogs' olfactory sense from the data, and the proof of that is that the dogs couldn't locate the jars containing food. Dogs should easily have been able perform that task, as anyone who operates a sniffer dog will confirm. The fact that these dogs couldn't do it means something is wrong, and I'd bet money that the problem was that the jars were handled in such a way that they all smelled of food. To be fair, this would be quite hard to get right. Dogs have a sense of smell that can seem downright supernatural. When I was in high school, Denver PD had a bloodhound named Yogi who tracked down the body of a murdered child who had been transported ten miles by car. Yes, by car [1]. In training exercises, Yogi was able to track things that had been sunk thirty feet underwater at a local reservoir. That craziness obviously presents an enormous challenge when designing a study on another hypothetical dog sense, and while this study went to some length to address it, something clearly slipped through the cracks such that the study's "food" arm (which was intended to serve as a control arm) was rendered useless. It also makes me strongly suspect that the magnets were also handled in such a way that there was some olfactory indication of which jars contained them. The paper doesn't tell us how the preparers handled the magnets and their containers, and there's no indication that they took measures to either prevent the transfer of any odor from the magnets to the jars, or somehow ensure that the odor was transferred equally to all jars. My skepticism notwithstanding, I'm fascinated by the concept of magnetoreception in animals, especially birds, and I think it definitely deserves extensive study. 1 - Look up the Alie Berrelez murder case.
- lupire 7y ago
  Police claimed that Yogi could smell whether a car carrying the victim had driven along the highway or down the exiat ramp, 4 days later. Supposedly the car exhaust blows your body cells out of the car and somehow into the ground but stays within a range of a few dozen feet. It doesn't pas the sniff test. Something else was going on, maybe a tip-off and the dog was cover for it. https://unsolved.com/gallery/alie-berrelez/ https://unsolved.com/gallery/alie-berrelez/
  - saghm 7y ago
    > It doesn't pas the sniff test. Was this pun intended? If so, well done!
  - nate_meurer 7y ago
    I've heard some conspiracy theories in my time, but that's surely one of the lamest. This was a search for a child who may still have been alive, and a suspect still at large. The cops were begging for tip-offs. Why in the fuck would they waste days or even hours with a fake search in order to "cover" for anything? Yogi worked out in the open, and he had an audience. Civilians were involved in the search, and in fact the body was actually found by a group of students who were assisting. People were able to watch the dog repeatedly lose the scent, backtrack, and pick it back up, working his way up into the canyon. That would be one hell of a dirty, dishonest performance by Yogi's handler, who by the way is still active in the K9 community. Nobody knows exactly how Yogi did it, but given that dogs are to known smell at parts-per-trillion levels, and that there are many ways the killer's scent could be transferred to his own car tires, I don't think it requires an excess of credulity to take the police at their word.

nate_meurer 7y ago

> Maybe you should have started with that, rather than anecdotal evidence. Oh dear. You mean I didn't approach this topic with the care it deserved? > High school students... Good for them! I only glanced at it, but it looks interesting. > Dogs can be trained to find a bar magnet... I read this. Right away, I can tell you the authors didn't take nearly enough care to eliminate the dogs' olfactory sense from the data, and the proof of that is that the dogs couldn't locate the jars containing food. Dogs should easily have been able perform that task, as anyone who operates a sniffer dog will confirm. The fact that these dogs couldn't do it means something is wrong, and I'd bet money that the problem was that the jars were handled in such a way that they all smelled of food. To be fair, this would be quite hard to get right. Dogs have a sense of smell that can seem downright supernatural. When I was in high school, Denver PD had a bloodhound named Yogi who tracked down the body of a murdered child who had been transported ten miles by car. Yes, by car [1]. In training exercises, Yogi was able to track things that had been sunk thirty feet underwater at a local reservoir. That craziness obviously presents an enormous challenge when designing a study on another hypothetical dog sense, and while this study went to some length to address it, something clearly slipped through the cracks such that the study's "food" arm (which was intended to serve as a control arm) was rendered useless. It also makes me strongly suspect that the magnets were also handled in such a way that there was some olfactory indication of which jars contained them. The paper doesn't tell us how the preparers handled the magnets and their containers, and there's no indication that they took measures to either prevent the transfer of any odor from the magnets to the jars, or somehow ensure that the odor was transferred equally to all jars. My skepticism notwithstanding, I'm fascinated by the concept of magnetoreception in animals, especially birds, and I think it definitely deserves extensive study. 1 - Look up the Alie Berrelez murder case.

lupire 7y ago
Police claimed that Yogi could smell whether a car carrying the victim had driven along the highway or down the exiat ramp, 4 days later. Supposedly the car exhaust blows your body cells out of the car and somehow into the ground but stays within a range of a few dozen feet. It doesn't pas the sniff test. Something else was going on, maybe a tip-off and the dog was cover for it. https://unsolved.com/gallery/alie-berrelez/ https://unsolved.com/gallery/alie-berrelez/
- saghm 7y ago
  > It doesn't pas the sniff test. Was this pun intended? If so, well done!
- nate_meurer 7y ago
  I've heard some conspiracy theories in my time, but that's surely one of the lamest. This was a search for a child who may still have been alive, and a suspect still at large. The cops were begging for tip-offs. Why in the fuck would they waste days or even hours with a fake search in order to "cover" for anything? Yogi worked out in the open, and he had an audience. Civilians were involved in the search, and in fact the body was actually found by a group of students who were assisting. People were able to watch the dog repeatedly lose the scent, backtrack, and pick it back up, working his way up into the canyon. That would be one hell of a dirty, dishonest performance by Yogi's handler, who by the way is still active in the K9 community. Nobody knows exactly how Yogi did it, but given that dogs are to known smell at parts-per-trillion levels, and that there are many ways the killer's scent could be transferred to his own car tires, I don't think it requires an excess of credulity to take the police at their word.