January 01, 2013

Mating between Modern Humans, Neanderthals and other Archaics (Waddell & Tan 2012)

arXiv:1212.6820 [q-bio.GN]

New g%AIC, g%AICc, g%BIC, and Power Divergence Fit Statistics Expose Mating between Modern Humans, Neanderthals and other Archaics

Peter J. Waddell, Xi Tan

The purpose of this article is to look at how information criteria, such as AIC and BIC, relate to the g%SD fit criterion derived in Waddell et al. (2007, 2010a). The g%SD criterion measures the fit of data to model based on a normalized weighted root mean square percentage deviation between the observed data and model estimates of the data, with g%SD = 0 being a perfectly fitting model. However, this criterion may not be adjusting for the number of parameters in the model comprehensively. Thus, its relationship to more traditional measures for maximizing useful information in a model, including AIC and BIC, are examined. This results in an extended set of fit criteria including g%AIC and g%BIC. Further, a broader range of asymptotically most powerful fit criteria of the power divergence family, which includes maximum likelihood (or minimum G^2) and minimum X^2 modeling as special cases, are used to replace the sum of squares fit criterion within the g%SD criterion. Results are illustrated with a set of genetic distances looking particularly at a range of Jewish populations, plus a genomic data set that looks at how Neanderthals and Denisovans are related to each other and modern humans. Evidence that Homo erectus may have left a significant fraction of its genome within the Denisovan is shown to persist with the new modeling criteria.



Blue Heron said...

I am not going to pretend to understand the math, but any scientific study that cites american porn actor Ron Jeremy has my vote.

"The apparent lack of Denisovan alleles on the X chromosome suggested that some of
these archaic interbreeding events were male biased, that is archaic males mating with modern
females (Waddell, 2011). This was formerly dubbed the “archaic Ron Jeremy” hypothesis, after
the well-known American thespian. Formerly known, because a journal editor has recently urged
us to alter our manuscript, to avoid confusion with a “Ron Jeremy Event”, which they referenced
to the Urban Dictionary. The new synonymy is the “lecherous archaic man” hypothesis. Looking
at the residuals, evidence for introgression of Homo erectus into the Denisovan is the marked
deficiency of the DSYFHP allele in contrast to a slight excess of the NSYFHP allele. "

shenandoah said...

Wow, I learn so much from Urban Dictionary; now I know what a "Ron Jeremy Event" is -- but I really don't understand what that has to do with the subject matter. Nevertheless, I've been saying all along that Denisovan and Neanderthal genes were ~introduced into particular AMHs' genomes through certain ~male lineages. Now the data is proving me correct about that at least. I only disagree about the chronology of the genes; because, I don't believe Denisovans and Neanderthals were true "archaics" -- I think they were Hybrids instead. And I don't believe the women they bred with should be called "modern" Humans -- I think they were original, fairly pure Human specimens instead. I believe those Hybrid species were bred from purely Human women, with lower Primate sires. I know that in itself sounds obscene, even horrific; but if you take into account the kinds of things which went on during those times (and even these days, unfortunately) -- it's really not that surprising. I don't believe they did it strictly for ~fun, or for their own 'pleasure', however... I'm sure it was more motivated by survival instincts and / or by greed (production of "slave races").

There is a lot of evidence to support my basic theory, and I've yet to find anything at all to refute it.

Roy said...

@ Shenandoah
Thanks for reminding me of Monty Python. "My theory by Ann Elk. A dinosaur was thin at one end, much much thicker in the middle, and thin again at the other end."

shenandoah said...

Sorry Roy, I never watched that show. The humor was just too juvenile for my taste. I've never cared for 'slapstick' humor.

terryt said...

'Life of Brian' is still the funniest film ever made.