One of your questions was:
> How do we know when a sample of constructs is big 
> enough and representative enough? 
You may have a look at:
 Rathod,P. (1981) Methods for the analysis of repertory grid
     data. In H. Bonarius, R. Holland & S. Rosenberg (Eds.), Personal
     construct psychology: Recent advances in theory and practice. London:
     MacMillan.
and 
Rathod, P. (1980)
     The reliability of the principal components of rep grid data.
     Nederlands Tijschrift voor de Psychologie, 35, 345-354.
Rathod collected 'big' grids and compared parameters of 'sub'grids
with parameters of the whole grid.
Kind regards
Rainer Riemann
-- _______________________________________________________________________________Rainer Riemann Phone: <0>521 106 4529 Universitaet Bielefeld Fax: <0>521 106 5844 Fakultaet fuer Psychologie e-mail: upsyf077@hrz.uni-bielefeld.de und Sportwissenschaft Postfach 100131 D-33501 Bielefeld _______________________________________________________________________________
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