Creationist karstology

I never knew there was a branch of science called ‘creationist karstology’. But now I know: probably the best known (and potentially the only) practitioner of it is Emil Silvestru, who was head scientist at the Speleological Institute in Cluj, Romania, before he immigrated to Canada and became a member – and apparently employee – of Answers in Genesis, a creationist organization. ‘Creation Magazine’ claims he is a ‘world authority on caves’ – OK, he probably did indeed spend some time in caves and knows something about them. But how seriously can you take someone who honestly thinks that this is reasonable and this is good science:

After becoming a Christian he quickly realized that the ‘millions of years’ interpretation, so common in geology, was not compatible with Genesis. ‘Once I became a Christian,’ Emil says, ‘I knew I had to “tune up” my scientific knowledge with the Scriptures.’

‘Although philosophically and ethically I accepted a literal Genesis from my conversion, at first I was unable to match it with my “technical” side.’

E-mail discussions with qualified creationist geologists, creationist books, Creation magazine and especially the TJ helped him realise what he calls two ‘essential things’:

  1. Given exceptional conditions (e.g. the Genesis Flood) geological processes that take an extremely long time today can be unimaginably accelerated.
  2. The Genesis Flood was global, not regional.

    ‘These factors were immensely important in my conversion and my Christian life. I am now convinced of six-day, literal, recent, Genesis creation. That doesn’t mean that there are not still some unanswered problems, but researching such issues is what being a scientist is all about.’”

According to Dr. Silvestru, radioactive dating is wrong; he is “now convinced of six-day, literal, recent, Genesis creation” and that “currently prominent creationist modeling of the post-Flood Ice Age is an important tool in understanding the karst in a young-earth framework“.

No comment.

To wrap it up, a little piece of blatant misinformation. Asked if he

experienced any ridicule or persecution because of his strong stand on Genesis creation

, I guess back in Romania, Dr. Silvestru says:

“Not really, for two main reasons. First, after so many years of almost compulsory atheism/evolutionism, most people welcome biblical creationism as a breath of fresh air. Second, God has granted me a professional status that practically bars any attempt to ridicule my creationist convictions.”

It is true that religion has gained quite some ground since the fall of communism in Eastern Europe; but I don’t think that you can make a blanket statement like “most people welcome biblical creationsim as a breath of fresh air”. In fact, most of the people I know, even those who are much more sympathetic toward religion then I am, would definitely not consider bibilical creationism a breath of fresh air.

Regarding his “professional status that practically bars any attempt to ridicule” his creationist convictions – well, here is one.

It is also true that they are ridiculous enough by themselves.

Power laws and log-log plots II.

Back again to power laws. After some more googling, I found an even more important piece of blogging by Cosma Shalizi: Speaking Truth to Power About Weblogs, or, How Not to Draw a Straight Line. The title says it all: just don’t play with power law distributions by fitting straight lines to log-log plots, because chances are that you will get a reasonably looking line and R squared will be relatively large, but that still does not mean that there is a power law distribution. Shalizi is complaining about papers in statistical physics and complexity theory that do such things — well, he should see what is going on in sedimentary geology, where somebody invented the ‘segmented power-law distributions’ and now everybody who is measuring bed thicknesses is fitting not one, but two or even more straight lines to log-log plots of cumulative distributions. It’s utter nonsense, even more so than with a single straight line, but it looks very sophisticated and regular, and people keep doing these plots and all kinds of fancy interpretations based on them (earthquakes, self-organizing criticality, confinement, erosion, etc.). If it plots as a straight line – fine, it’s a power law, we explained everything. If it does not plot as a straight line — well, just fit two straight lines and talk about two populations, and how the original power-law distribution has been modified by erosion, confinement, etc. – and we explained everything again. I know I am also guilty of some of this in my thesis, but at least I have never done the segmented power law plots.

Power laws and log-log plots I.

Did a bit of reading today on power law distributions, just to refresh my memories from three years ago when I was writing my thesis. And found some interesting papers and notes on the web, e.g., this one. I think we are still far from being able to use bed thickness distributions in a useful, predictive way, even though this has become a popular subject among turbidite experts. One of the problems is that it is easy to play with the distributions (e.g., take an initial power-law distribution and modify it by amalgamation), but things are probably a lot more complicated and cannot be explained just with amlagamation and basin topography. The other problem is that power-law distributions and their exponents cannot be assessed by fitting a straight line to an exceedence probability plot, as it is explained here. This method is bound to give erroneous estimates when dealing with a single distribution, but it is close to meaningless when people want to break out two different populations by fitting not one, but two lines to the exceedence probability plot.

Well, I guess that is enough about power laws for today.