"Knox's "accusation" of Lumumba amounted to no more than saying "Well, all right, I guess maybe he could have done it.""
I don't want to cause you to rehash arguments you've had here already. There are so many other pieces of evidence of equal value as her 'lie'. I am aware of the circumstances under which Lumumba was mentioned. At the moment all we can say about the circumstances are that she says she was slapped twice on the back of the head and shouted at, they say they didn't. Perhaps evidence will be produced by one side or another at the slander hearing. It's clear though that she, or possibly her family, has been less than truthful about the length of time she was interrogated for.
As for her statement about Lumumba. She said it in her interview ending at 1:45, she repeated it in her statement finishing at 5:45, she repeated it in the "gift" she wrote the following day. Admittedly it is all couched in the "half remembered dream" language of hers.
"To "lie" is to make an assertion that one knows to be false"
True. I think she is lying. I find it very difficult to believe that in hour ever much of the hour and fourty five minutes of questioning remained after they got onto the text message she became so confused that for two weeks until Lumumba's alibi came good she was unsure whether what she had said about having been there and listened to Meredith's screams was a dream or a half remembered truth.
"It does not constitute a positive assertion about the state of the world, and thus cannot be a "lie"."
Philosophically I agree with you. I just don't think it was sensible of her to make, and then repeat, statements to the police that one has to defend on the grounds that they are do not consitute positive assertions.
"Now, definitions don't matter, of course; but the point is that the lack of correspondence between this particular account and the actual reality of the situation is not Bayesian evidence of her having wished to deceive police about her state of knowledge (which would in turn be Bayesian evidence of her guilt)."
How about the false alibi about the party, and the false alibi of using the computer? How many innocent people get caught in two false alibi's? I'm excluding the alibi where she said she was home all night and he said she went out.
How about this:
What are the odds that, given a murder in a shared accomodation, one of the occupants is involved if someone known to one of the occupants is known to be involved, more than one person is known to be involved, and that occupant is found to have a false alibi?
"If Amanda Knox and Raffaele Sollecito were to be in investigators' thoughts at all, they had to get there via Guédé -- because otherwise the hypothesis (a priori unlikely) of their having had homicidal intent toward Kercher would be entirely superfluous in explaining the chain of events that led to her death."
They have fake alibi's, a crime scene they believed had been tampered with to conceal evidence, the whole Lumumba story from Knox and evidence from the body suggesting multiple people were involved in the murder. I'm not sure that these are things it's trivial to assign probabilities to in order to work out the odds of anybody's guilt or innocence.
"The hypotheses of Knox's and Sollecito's guilt are thus seen to be completely unnecessary, doing no explanatory work with respect to Kercher's death. They are nothing but extremely burdensome details."
Again, the body appeared to show the work of multiple attackers. Knox and Sollecito had lied about their alibi; Guede appeared to have an alibi for the time the police believed the body was moved. Whoever cleaned up after the murder (which the police believed occurred) clearly made little attempt to hide evidence pointing to Guede.
What are the odds of these events given Amanda being innocent and Amanda being guilty? Can anybody tell within a couple of order of magnitude?
Given a murder in a shared house, what is the a priori probability that somebody from that house was involved? 0.1? 0.01?
Surely you are comparing the combined probability of various events whose individual probability you can only guess at and not all of which you may know, that have complex interdependencies and comparing that number against another number that you don't know with any certainty. The likelihood of being out by a very great margin in such a calculation is large.