Re: NPAR TESTS

Michael Kiefte <[email protected]> writes:

> Actually, there's several that need the rank.  W. S-R is a little more 
> complicated than that even: you have to pool the scores from both variables, 
> then assign the ranks and then put them back in the right variables.  There's 
> a number of stats like that.

Can you think of a few of the others off-hand?  I like to try to
look forward when I write code, so that I can generalize as much
as necessary (but not more).

> I'll leave rank to you, but I will need it for quite a number of tests.  I'll 
> work on the simpler ones for now.

Okay.

>> Wouldn't surprise me if they could.  It's basically a sort, and
>> external sorts are not difficult to write.  They probably just
>> reuse the code from SORT CASES, the same way I'm planning to do
>> for RANK.  It might take a little extra effort because you have
>> to do *two* sorts--the first to get the ranks and the second to
>> restore the same case ordering as in the active file--but
>> certainly doable.
>
> The added complication is that if you have 2 or more observations with the 
> same rank, their rank is the weighted mean of the ranks they would otherwise 
> be assigned.  That requires looking ahead in the sorted temp file or seeking 
> back.

Shouldn't be too bad then.
-- 
Ben Pfaff 
email: [email protected]
web: http://benpfaff.org