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Re: Statistical analysis of the DPL 2005 election

* Anthony Towns <aj@azure.humbug.org.au> [2005-05-09 14:42]:

> Well, subjective and speculative is fine -- but is completely
> irrelevant to the statistics. We've got plenty of places where you and
> others can be subjective and speculative about the results; the whole
> point of doing a statistical analysis is to be evidence and fact
> driven, surely?

Yes.  Perhaps I should change the title of my paper...

> I can understand you including your own speculations -- I mean, you 
> wrote the analysis -- but I don't think that's a good idea, and it 
> certainly seems a bad idea to include anyone else's.

I think the opinions are sound, albeit necessarily speculative. Of
course, this is a matter of personal opinion, but I really do not see a
problem in including the opinion of others in in the paper.

> Err. By my count, I was ranked last on 50 ballots, Branden was ranked 
> last on 65 ballots. Branden likewise was ranked first on more ballots 
> than I was (144 versus 136). If you don't canonicalise the results, the 
> only rankings I receive more of the Branden are [3], [4], and [5], 
> Branden gets more of each of [1], [2], [6], [7], and [-].
> So, afaics there's some misinterpretation going on there: if "AT versus 
> the world" was the meaning of the "factor", "BR versus the world" should 
> have been a slightly stronger one.

These are sensible arguments.  I have to think further on that.

> I don't know the statistics; but if "factor" means something similar to 
> "vector basis", then I would've said it meant that "in choosing 
> rankings, people tended to rank AT independently of other candidates". 
> ie, that people first decide how they're going to rank NOTA, Angus and 
> Jonathan (which tended to have a significant influence on how they 
> ranked Matthew); then they decide how to rank me (which has no influence 
> on how they rank anyone else); then they decide either how to rank Team 
> Scud, tending to favour Branden; or they decide how to rank Branden 
> which influences how they rank Andreas.
> If that were the case, then "AT versus the world" would be a graph with 
> values (-1, -1, -1, 1, -1, -1, -1), not more or less (0,0,0,1,0,0,0).

Your argument works with both vectors above.  Notice that they are
colinear, there is just a change of origin (plus a scaling) to get one
from to the other:

    if a = (-1, -1, -1, 1, -1, -1, -1) and b = (0,0,0,1,0,0,0),
    then b = (a + 1)/2;

> If it is independence that's being measured; you'd want to explain why 
> people tended to vote other candidates together (do I like foo? then I 
> like bar as well, and dislike baz) but not me. Possible explanations 
> might be that I had a confusing mishmash of policies compared to other 
> candidates so had to be thought of separately; or that I explained my 
> policies more clearly so that people could form their own opinions of 
> me; or that my platform was "out there" enough that people couldn't help 
> but form their own opinion of me; or something else.
> That's a different line of thought than "It may be interpreted as a 
> tendency to differentiate candidate AT, by ranking it either much higher 
> or much lower than the others candidates" though.

I understand both paragraphs above as being similar, but I agree that my
wording may give raise to some ambiguous (or erroneous) interpretations.
I might consider making some revision in the text soon.  At any rate, I
thank you for this insightful discussion.


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