Where your matrix is A1:C15 and D1 contains the i-th element your looking
for, try

=COUNTIF(B1:B15,INDEX(B1:B15,D1))=8

If your table is dynamic and you always want to count the i-th element from
the second column, try:
=COUNTIF(INDEX(MATRIX,0,2), INDEX(INDEX(MATRIX,0,2),D1))=8
where MATRIX is your named range.

"pete" wrote:

i am interested in performing a task that will describe in terms of
pseudo-code:

if i were doing this with a programming language, then i would write a
program that takes in a matrix as a parameter. this would be an n x 3
matrix. i would then get the second column vector (representing
products) and iterate through it. i would check whether the count of
the i-th element in the vector is greater or equal to 8.

i guess i can try to invest time for trying to do this in VB but i'd
rather not; my data is in an Excel worksheet so i want to just that
application

the Excel Help page for Advanced Filter is not too helpful with respect
to what i want to accomplish

many thanks,

pete