tag:blogger.com,1999:blog-1812431336777691886.post4718827353660369369..comments2024-02-29T03:57:00.088-05:00Comments on The Mermaid's Tale: Why is the cause of X (or Y or Z) so hard to find?Anne Buchananhttp://www.blogger.com/profile/09212151396672651221noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-1812431336777691886.post-53631868733478145622013-07-24T08:54:10.531-04:002013-07-24T08:54:10.531-04:00Hey, as a former weather forecaster, I take except...Hey, as a former weather forecaster, I take exception to your remarks! Actually, what makes a forecast 'right' depends on the need. What proper forecasting does these days is mainly, or only, probabilistic and based on a mix of theory plus the recorded experience of similar conditions.<br /><br />Long-term forecasting is accurate if you say that there will be less rain in the fall, sub-zero temperatures in winter, etc. But it's useless for reasons you discuss for details.<br /><br />In other areas, like personalized genomics, there's also a mix. Some genotypes are far more highly predictive than most. So, as you say, the problem is the misleading generalized promises that give the impression things are far more precise than they are--and, also as you concluded, a probabilistic forecast for an individual is unfalsifiable!Ken Weisshttps://www.blogger.com/profile/02049713123559138421noreply@blogger.comtag:blogger.com,1999:blog-1812431336777691886.post-38306679124238047802013-07-24T08:47:39.586-04:002013-07-24T08:47:39.586-04:00A fascinating episode of the BBC radio program Dis...A fascinating <a href="http://www.bbc.co.uk/programmes/p01c4qgt" rel="nofollow">episode </a>of the BBC radio program Discovery highlights another example of the difficulties determining cause, in this case earthquakes. Substitute "disease" for "earthquake" and we're right back in familiar territory. <br /><br />Predicting earthquakes with any degree of precision as to timing and severity is essentially impossible, even if the general cause has been known since plate tectonics was understood. Some quotes from the program: "There are things that are unknowable." "What should we tell the public?" "We admit that we cannot predict earthquakes with any high accuracy but we can monitor and see if any significant changes occur." "Should we evacuate a city 200 times, because one time might be "the one"?"<br /><br />Finally, one of the guests told a famous story by Kenneth Arrow, Nobel Prize winner in economics. He was a weather forecaster in the Army, and one of his tasks was to prepare forecasts for the upcoming month. After some time he ran the statistics and realized these forecasts were no better than random. He told this to the general requesting them, and the general replied, "I know they're no good, but I want them for my planning purposes." <br /><br />Everyone wants to know more than meteorology, or geology, or genetics, or epidemiology is capable of telling. Luckily for scientists a prediction of 30% risk is always right -- they're right if it happens and right if it doesn't. Anne Buchananhttps://www.blogger.com/profile/09212151396672651221noreply@blogger.com