Dana
> To add just a bit. The author used one form of factor analysis I
> don't necessarily like, called principle components analysis. Without
>
> going into detail it makes some assumptions about how the individual
> items are related to each other, frequently overestimating this
> communality. Its good for a first estimation of the underlying
> factors, and for the initial development of a questionnaire, but for
> determining the actual structure of the factors involved, I think its
>
> inadequate.
>
> I'll be downloading the data today and using some other analysis on
> it later today and see what I come up with.
>
> larry
>
> >I think that this survey is much more valid than the other ones we've
> tried.
> >
> ><http://politics.beasts.org/>http://politics.beasts.org/
> >
> >FWIW, here are my scores:
> ><http://politics.beasts.
> org/scripts/results?surveyid=838428544>http://politics.beasts.
> org/scripts/results?surveyid=838428544
> >
> >Axis Position
> >1 left/right -7.2199 (-0.4346)
> >2 pragmatism +2.2182 (+0.1335)
> >
> >Anyhow the following is part of the rationale of the survey given by
> >its authors.
> >--
> >politicalcompass.org is a web site which asks a number of opinion
> >questions of its visitors, and then places them in a two-dimensional
> >space which is supposed to characterize their political views.
> >Unfortunately, politicalcompass.org has a poor reputation; in
> >particular, there is a suspicion that its questions are designed to
> >make respondents lean towards an economically right-wing, socially
> >liberal ("right libertarian") position, and the two axes of
> variation
> >on which results are plotted are opaque in their derivation and may
> >not be tremendously relevant.
> >
> >These suspicions are compounded by the problem that
> >politicalcompass.org's methods are not open and, therefore, it is
> not
> >possible to determine whether their selection of questions carries a
> >bias which its operators are using to further their own ends.
> >
> >The purpose of this site is to do a survey of this type properly and
> >openly, so that the methods and data in use are open to inspection.
> >More detail
> >
> >The proper way to do this is to collect a bunch of questions and a
> >bunch of answers to them, then take the space defined by all the
> >answers to the questions, and construct a spanning basis for it. The
> >natural way to do this is with principal components analysis, though
> >as a non-statistician I can't comment on whether this is actually
> the
> >best approach. We should then be able to discover -- in terms
> defined
> >by the answers to the questions set -- the significant axes of
> >variation in the data.
> >
> >This means that all the results we get are defined by the data: we
> do
> >not measure anyone's views according to criteria we set out, but
> >according to endogenous criteria. The only points at which our
> >judgment enters the method are
> >
> > * when choosing questions (or, rather propositions); and
> > * when we give context to the results.
> >
> >The first of those shouldn't matter, if the questions are reasonably
> >unbiased and cover a wide enough range of subject materials. The
> >second doesn't matter, since it's just a presentational issue.
> >--
> >
> >So far I'm going over their analysis, and looking at how they did
> the
> >factor analysis, it looks pretty good so far. I'm going download
> >their data over the weekend and run it through a few of my stats
> >programs (SPSS for the factor analysis and AMOS for the causal
> >modelling/path analysis) and see if it holds. but my first
> impression
> >by looking at their published eigenvectors, is that it looks legit.
> >
> >larry
> >
>[
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