So you agree then, that you mischaracterized the prosecution's argument?
Not in any way that makes their case seem weaker than it actually was.
I'm not sure I understand your point. You seemed to be arguing that the amount of DNA traces left by Guede were "orders of magnitude" above the detection threshhold, i.e. at least a hundred times higher. And that if Knox or Sollecito had been in physical contact with Kercher, they would have left at least a hundredth of the DNA left by Guede -- enough to have been unambiguously detected.
The traces left by Guede were all above the limit of quantification. The only piece of evidence on the scene that contained traces above the limit of detection for anyone other than Kercher or Guede was the bra clasp, which contained DNA from Kercher as the major contributor, and DNA above the limit of detection but below the limit of quantification for several other people, according to the independent experts' report, DNA which they claim was most likely due to mishandling and contamination. That leaves no traces above the limit of detection from any uncontaminated source for any potential perpetrator other than Guede, so if we are to posit that anyone else was involved, we must suppose that they did it while shedding orders of magnitude less biological material.
Ok, and assuming that's true, they would have had a strong motive to do more swabs right? And if they in fact did so, then under your hypothesis, they should have found additional Guede DNA material, right?
By the time they went to retrieve further evidence, Meredith Kercher had already been buried. Her body, along with the objects on which they had found traces of Guede's DNA, had already been removed. They did not re-swab her body to see if they could get more of Guede's DNA off of it, nor did they attempt to see if they could get more traces from any of the other articles on which they had already found his DNA. Had they scoured the scene for more traces of Guede, I would be surprised if they did not find any, but they weren't looking for more traces of Guede, they were looking for traces of Knox and Sollecito. Further traces of Guede found on the scene 47 days later might not even have been kept due to their lesser value as evidence since there was already plenty of opportunity for corruption and the case against him was rock solid; if they found, say, small traces of his DNA on the floor on the reexamination, they'd have no particular reason to make note of it.
And what classes did you take which gave you your expertise in forensics?
Two semesters of biology labs covered forensics. My labs in atmospheric and environmental chemistry also dealt with collection and analysis of trace chemicals from a scene.
Not in any way that makes their case seem weaker than it actually was.
Umm, does that mean yes or no?
The traces left by Guede were all above the limit of quantification.
Umm, does that mean yes or no? And what are the numerical limits for quantification and detection?
By the time they went to retrieve further evidence, Meredith Kercher had already been buried.
Umm, does that mean yes or no?
...Had they scoured the scene for more traces of Guede, I would be surprised if they did not find any, but they weren't looking for more traces of Guede, they
Continuing my interest in tracking real-world predictions, I notice that the recent acquittal of Knox & Sollecito offers an interesting opportunity - specifically, many LessWrongers gave probabilities for guilt back in 2009 in komponisto’s 2 articles:
Both were interesting exercises, and it’s time to do a followup. Specifically, there are at least 3 new pieces of evidence to consider:
Point 2 particularly struck me (the press attributes much of the acquittal to the expert report, an acquittal I had not expected to succeed), but other people may find the other 2 points or unmentioned news more weighty.
2 Probabilities
I was curious how the consensus has changed, and so, in some spare time, I summoned all the Conscientiousness I could and compiled the following list of 54 entries based on those 2 articles’ comments (sometimes inferring specific probabilities and possibly missing probabilities given in hidden subthreads), where people listed probabilities for Knox’s guilt, Sollecito’s guilt, and Guede’s guilt:
It’s interesting how many people assign a high-probability to Knox being guilty; I had remembered LW as being a hive of Amanda fans, but either I’m succumbing to hindsight bias or people updated significantly after those articles. (For example, Eliezer says .15 is too high, but doesn’t seem otherwise especially convinced; and later one reads in Methods of Rationality that "[Hagrid] is the most blatantly innocent bystander to be convicted by the magical British legal system since Grindelwald's Confunding of Neville Chamberlain was pinned on Amanda Knox.")
EDIT: Jack graphed the probability against karma:
2.1 Outliers
If we look just at >41% (chosen to keep contacts manageable), we find 12 entries out of 54:
I have messaged each of them, asking them to comment here, describing if and how they have since updated, and any other thoughts they might have. (I have also messaged the first 12 commenters or so, chronologically, with <41% confidence in Knox’s guilt, with the same message.) The commenters:
AngryParsley / Cyan / Daniel_Burfoot / Eliezer_Yudkowsky / GreenRoot / John_Maxwell_IV / LauraABJ / Mario / Matt_Simpson / Morendil / Psychohistorian / Shalmanese / Threads / Unknowns / badger / bentarm / bgrah449 / bigjeff5 / brazil84 / dilaudid / jimmy / kodos96 / lordweiner27 / mattnewport / nerzhin / tut
I look forward to seeing their retrospectives, or indeed, anyone's retrospectives on the matter.