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　　“坏科学的典型例子”——Susan Hough评“癞蛤蟆报地震”论文

　　作者：Amsel

　　这两天媒体报导英国有研究人员“发现”蟾蜍能够预报地震，论文发表在
Journal of Zoology上面。中文媒体也有翻译报导。Discovery.com的一位博客
作者就此请教了Susan Hough（她是美国地质调查局和加州理工学院工作人员，
经常在地震之后出面向公众介绍地震知识），Susan Hough做了回答。

　　http://news.discovery.com/earth/can-toads-predict-earthquakes.html

　　In order to take a serious look at whether this toad thing has 
anything to it — and whether the little buggers were somehow able to 
read electrical signals from the edge of space — I consulted with 
Susan Hough, a seismologist at Caltech. After having a read of the 
paper, here’s what she had to say:

　　This is a good example of bad science. The earthquake prediction 
heyday of the 1970s was launched and sustained by similar studies: 
people who found snippets of data after the fact that showed an 
apparent correlation between some signal and an eventual earthquake. 
This is not good statistics. You can’t select data after the fact.
　　【翻译：这是坏科学的典型例子。在地震预报高潮的1970年代，曾经开展这
类研究：一些人在地震之后找到一些片段的数据，来说明某些信号和最终发生的
地震之间的明显的关系。这不是好的统计学。你不能在事件发生后去选择数据。】

　　In this case, there’s no way to know what kind of fluctuations 
are normally seen in toad activity, or what else might have been going 
on in the study area that could have influenced toad behavior.
　　【翻译：在这个例子里，没有办法知道蟾蜍活动的什么样的波动属于正常现
象，或者研究区什么其它过程有可能影响到了蟾蜍的行为。】

　　It is within the realm of possibility that there are precursory 
signals before some earthquakes, and that animals might respond to them. 
But to demonstrate a significant correlation one would need to have a 
long record of objectively-recorded data before and after many 
earthquakes.
　　【翻译：确实有这样的可能性：在某些地震之前存在前兆信号，并且动物对
这样的信号有反应。但是，要展示一个有意义的关联，研究者必须在多次地震之
前和之后进行长期客观的数据记录。】

　　On the question of the ionosphere, she added:

　　There have been a number of studies of satellite observations that 
approach the bar for good science, in terms of applying rigorous 
statistics, etc. And, again, it is within the realm of possibility 
that VLF [Very Low Frequency] precursors exist.

　　But the snippets of data shown are insufficient to draw conclusions.

　　…
　　There are really two questions: 1) do precursors exist, and 2) do 
useful precursors exist? It is possible that precursory signals — 
electromagnetic, whatever — are generated in the earth prior to SOME 
earthquakes, but these precursors, if they exist, will have no 
predictive capability if they do not reliably occur before large 
earthquakes, and only before large earthquakes.
　　【翻译：（地震前兆）有两个问题：（1）前兆存在吗？（2）可用的前兆存
在吗？在某些地震之前有可能产生前兆信号——电磁的或者别的什么的，但是，
这样的前兆，如果存在的话，并没有预报意义，除非它们在大地震之前可靠地存
在、并且只在大地震之前存在。】

(XYS20100403)

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