A variable was categorized into 10 equally spaced intervals from a continuous variable which was originally in proportion. Now, we have to use this variable in CATREG procedure. If we choose the optimal scaling level to be 'ordinal' then quantification for the last seven categories are the same. That means the observations that originally had values ranging from 0.31 to 1.00, now receive the same quantified value after optimal scaling. If we use 'numeric' as the quantification level instead then different categories receive different quantification (as it should be).
But is using 'numeric' as the optimal scaling level valid here? Although the variable was numeric originally, but later that was transformed to an equally spaced 10-category variable. Note that, using 'nominal' gives quite different quantification, but some of the category quantification is still the same. I guess keeping in mind the nature of the original variable, different categories should not receive the same quantification. Could someone please clarify this?