tag:blogger.com,1999:blog-15005476.post5094873718217244310..comments2023-10-10T08:02:18.073-04:00Comments on Rationally Speaking: The logic of skepticismUnknownnoreply@blogger.comBlogger11125tag:blogger.com,1999:blog-15005476.post-82489114833900773332009-10-04T01:07:53.766-04:002009-10-04T01:07:53.766-04:00"This will not get you many girls and drinkin..."This will not get you many girls and drinking buddies, though."<br /><br />Ergo, all skeptics are hetero men or lesbians...c'est mahttps://www.blogger.com/profile/17273372778953145396noreply@blogger.comtag:blogger.com,1999:blog-15005476.post-48987902203090625122009-09-07T09:51:58.856-04:002009-09-07T09:51:58.856-04:00Massimo,
It may not be necessary to abandon null ...Massimo,<br /><br />It may not be necessary to abandon null hypothesis testing altogether. There's lots of methodology for equivalence (and non-inferiority) testing within the frequentist framework. When testing the efficacy of a new drug versus an existing drug for the same condition, the null hypothesis is generally taken to be that the new drug is inferior to the old one. This is a choice that our society makes to put the burden of proof on the new drug.<br /><br />When it comes to safety (of drugs, chemicals, products ...), society also has choices to make. Are new products taken to be "innocent until proven guilty", or must they be demonstrated to be safe. Which of course begs the question, "How safe?". (The "margin of equivalence" is a specification of this.)Nick Barrowmanhttps://www.blogger.com/profile/11224940659269649220noreply@blogger.comtag:blogger.com,1999:blog-15005476.post-87342482752820126832009-09-07T09:29:36.338-04:002009-09-07T09:29:36.338-04:00Nick,
right. That's precisely why I added the...Nick,<br /><br />right. That's precisely why I added the caveat at the end on the fact that there are better ways to think about this than null hypotheses.<br /><br />We should consider all competing claims as separate hypotheses, each to be individually weighed against the available information. Both Bayesian and likelihood analyses do this very well.<br /><br />Still, in the specific case you mention, if one wishes to remain within the "frequentist" approach (using a null hypotheses, p-values, etc.) one would probably say that no chemical is the default/safe and should be the null hypothesis, while adding a chemical has potentially negative effects. Analogously, in the case of a new drug, the null would have to be that the drug has no beneficial effects, and so on.Anonymoushttps://www.blogger.com/profile/09099460671669064269noreply@blogger.comtag:blogger.com,1999:blog-15005476.post-16599558504419761502009-09-07T09:07:48.855-04:002009-09-07T09:07:48.855-04:00Let's take a particular case: the safety of dr...Let's take a particular case: the safety of drugs or chemical products. <br /><br /><i>A skeptic in the modern sense of the term, let’s say from Hume forward, is someone who thinks that belief in X ought to be proportional to the amount of evidence supporting X.</i><br /><br />So what is X in this case? Is it "The chemical is safe" (X1)? Or is it "The chemical is harmful" (X2)? The manufacturer is likely to claim X1, while the health activist is likely to claim X2.<br /><br /><i>Whenever confronted with a new claim, it’s reasonable to think that the null hypothesis is that the claim is not true. That is, the default position is one of skepticism.</i><br /><br />But in this case, it's not clear which claim should be treated with skepticism.Nick Barrowmanhttps://www.blogger.com/profile/11224940659269649220noreply@blogger.comtag:blogger.com,1999:blog-15005476.post-87642142242466323652009-09-06T17:37:22.031-04:002009-09-06T17:37:22.031-04:00This an exceptionally important point, and its vit...This an exceptionally important point, and its vital even for trained scientists to be reminded of it, especially in medical fields where the number of claims are even higher and harder to prove than in other fields.<br /><br />A couple of my favorite papers on this subject:<br /><br />http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1182327<br /><br />http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=11159626Ougaseonhttps://www.blogger.com/profile/14579017934839315673noreply@blogger.comtag:blogger.com,1999:blog-15005476.post-46559697825963457022009-09-04T23:08:08.377-04:002009-09-04T23:08:08.377-04:00One thing you don't address explicitly here ar...One thing you don't address explicitly here are the relative risks inherent in type 1 and type 2 errors and how that should change our approach to belief acquisition (or at least our actions). So sometimes, it is important not to miss a "true positive" and sometimes it is important not to accept a "false positive." The technical details don't change, but our approach to the evidence should (although here the difference between *acting as if* and "believing that* might be important... How should our actions be related to our beliefs???Jonathanhttps://www.blogger.com/profile/11364316598293820961noreply@blogger.comtag:blogger.com,1999:blog-15005476.post-34593313588067181462009-09-04T21:32:56.045-04:002009-09-04T21:32:56.045-04:00I just started teaching a 9th grade biology course...I just started teaching a 9th grade biology course this year. I started off the class with the questions What is Science and What is Biology and discussed skepticism, and this article from Michael Shermer<br /><br />http://www.scientificamerican.com/article.cfm?id=what-skepticism-reveals<br /><br />Bringing up the next generation of skeptics!Alpha Geekhttps://www.blogger.com/profile/05685765745117778122noreply@blogger.comtag:blogger.com,1999:blog-15005476.post-14804080727672058552009-09-04T17:35:30.055-04:002009-09-04T17:35:30.055-04:00Tony,
the paper I was referring to is a chapter i...Tony,<br /><br />the paper I was referring to is a chapter in my book with Jonathan Kaplan:<br /><br />http://www.press.uchicago.edu/presssite/metadata.epl?mode=synopsis&bookkey=198161Anonymoushttps://www.blogger.com/profile/09099460671669064269noreply@blogger.comtag:blogger.com,1999:blog-15005476.post-72537543479996647762009-09-04T17:30:24.812-04:002009-09-04T17:30:24.812-04:00Massimo
The null hypothesis paper sounds really i...Massimo<br /><br />The null hypothesis paper sounds really interesting. Has it appeared? If so where? If not can I get you to send me a copy, or is it posted anywhere on the net?Tony Lloydhttps://www.blogger.com/profile/03740295390214409286noreply@blogger.comtag:blogger.com,1999:blog-15005476.post-85425271526863914792009-09-04T16:48:26.509-04:002009-09-04T16:48:26.509-04:00EXCELLENTLY put.EXCELLENTLY put.Joshuahttps://www.blogger.com/profile/13061133554890562130noreply@blogger.comtag:blogger.com,1999:blog-15005476.post-34250423648619204112009-09-04T11:20:07.563-04:002009-09-04T11:20:07.563-04:00You might like to look at the work of Fiona Fidler...You might like to look at the work of Fiona Fidler on null hypotheses, if you don't already know her work.John S. Wilkinshttps://www.blogger.com/profile/04417266986565803683noreply@blogger.com