The Discovery Institute have once again listed their top stories of the year.
Unlike last year, when their top 10 didn’t include anything by anyone associated with Intelligent Design, this year’s top ten do include some stories which involve DI fellows, albeit not about them doing research.
Their top story this year is about Casey Luskin’s misuse of genome statistics, which I’m surprised at[1] since it led to Luskin being exposed as having so blatantly manipulated an image (to hide data that contradicted his claims) that even the DI couldn’t stomach the level of dishonesty on display, and a revised version of his article was published with the real image included.[2]
But in the furore over Luskin’s dishonesty and hypocrisy, I - and possibly everyone else - missed another problem with his original article. Here’s an extract:
At least 12.5 percent and possibly up to 13.3 percent of the chimp and human genomes represent a “gap difference” between the two genomes. That means there’s a “gap” in one genome compared to the other, often where they are so different, they cannot even be aligned.
There are also significant alignable sections of the two genomes that show “short nucleotide variations” which differ by only about 1.5 percent. We can add this difference to the “gap difference,” and calculate a 14 percent to 14.9 percent total difference between human and chimp genomes.
That doesn’t work. Luskin has added the % that is different in the alignable sequences to the % of the genome that is unalignable. Those are different measures and can’t be added together any more than you can add 3 fish to 4 cakes and get 7 fishcakes.
The correct way to calculate the total difference isn’t 12.5+1.5=14, but (100×12.5/100)+(1.5×(100-12.5)/100) = 13.8.
It may not make much difference to the overall result in this case, but that’s (i) just luck, and (ii) no excuse for Luskin getting it wrong. If the numbers had been, say, 70% of the genome being unalignable and the alignable sections of the genome being 40% different, Luskin’s method of calculating the overall difference would have given a ‘result’ of 70+40=110% of the human genome being different from the chimp genome - which is clearly impossible. So he’s using the wrong calculation.
The furore over Luskins’s image manipulation might excuse anyone outside the DI from picking this up, but this article should have been checked before that furore began. Which means either it wasn’t checked, or the person who checked it was as bad at high-school mathematics as Luskin seems to be, or (most likely) the DI simply don’t care about whether their output is correct, only about whether their followers will notice the errors.
Added: I was just about to add a footnote about what should have been the result instead of 13.3+1.5=14.9 when I noticed that 13.3+1.5 is 14.8, not 14.9. Unless Luskin has copied across a rounding error - which is extremely unlikely since Luskin is summing two quantities that shouldn’t be summed - this article includes an error that could have been picked up by the average twelve-year old. Perhaps they could hire one as a proof-reader.
Though I probably shouldn’t be. ↩︎
The #1 article isn’t the one with the manipulated image, or the revised version with the ridiculous excuse, but the precursor to them, in which Luskin introduced the topic and promised more details. I’ll leave the DI to explain how a prelude can be a more important story than the event itself. ↩︎