Why does using a variable create an error?

theace

Can anyone explain why, in JMP 8

summarize(qlow=quantile(8,0.25))

works as desired (putting the 0.25 quantile statistics of the 8th column into variable qlow), but

::aa=8;

summarrize(qlow=quantile(::aa,0.25))

gives the error message
 

Column not found in access or evaluation of 'aa' , ::aa

?

pmroz

This works:

summarize(qlow=quantile(column(::aa),0.25));