[Rasch] Rasch analysis of interval data

Stephen Humphry shumphry at cyllene.uwa.edu.au
Thu Jul 24 05:57:21 EST 2008


Quoting Theo Dawson <theo at devtestservice.com>:

> Rasch modeling, combined with some trig, shows that cognitive
> development is well-represented by a sequence of sine waves.
> Performances can be assigned to points along this wavy continuum, even
> though developmental progress is not smooth. Each point along the
> continuum has a specific meaning, including implications for
> understanding, behavior, and learning. If this isn't measurement, then
> we need a new definition!

How do you define a "wavy continuum"? Waves exist in media, which are  
continuous; most often space and matter within space. In general,  
waves pre-suppose a continuous quantitative media within which they  
are propogated. I cannot see why you claim a new definition of  
measurement is needed.

If development can be characterised in such a way, there ought to be  
evidence of basic wave phenomena -- interference, diffraction,  
refraction, polarisation, etc. (depending on kind of wave and what it  
represents, longitudinal or transverse). Otherwise, it is unclear what  
evidence supports the proposition.

Steve




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