Ascending Rank uses dense ranking – is this deliberate?
24 January, 2014
In using the advanced function 'ascending rank' I noticed that it uses dense ranking rather than standard ranking - is this deliberate?
Wikipedia:
[quote="">In dense ranking, items that compare equal receive the same ranking number, and the next item(s) receive the immediately following ranking number. Equivalently, each item's ranking number is 1 plus the number of items ranked above it that are distinct with respect to the ranking order.
Thus if A ranks ahead of B and C (which compare equal) which are both ranked ahead of D, then A gets ranking number 1 ("first"), B gets ranking number 2 ("joint second"), C also gets ranking number 2 ("joint second") and D gets ranking number 3 ("third").[/quote]
Here's a screenshot of it happening:
Is this behaviour deliberate? I would personally prefer standard ranking but I can imagine others may not.
Wikipedia:
[quote="">In dense ranking, items that compare equal receive the same ranking number, and the next item(s) receive the immediately following ranking number. Equivalently, each item's ranking number is 1 plus the number of items ranked above it that are distinct with respect to the ranking order.
Thus if A ranks ahead of B and C (which compare equal) which are both ranked ahead of D, then A gets ranking number 1 ("first"), B gets ranking number 2 ("joint second"), C also gets ranking number 2 ("joint second") and D gets ranking number 3 ("third").[/quote]
Here's a screenshot of it happening:
Is this behaviour deliberate? I would personally prefer standard ranking but I can imagine others may not.
Hi Max,
yes it is deliberate, at the time of implementing this function our major clients were asked which they preferred and they all went for dense ranking.
I guess the problem with standard ranking is that if 2 rows are equal in rank then how should it be decided which of 2 equal rows gets the higher ranking. In the above Wikipedia example you would have to decide whether B should be given the rank of 2 and C the rank of 3, or the other way around. Then if a user gave a quick glance at the report they might erroneously assume that B was higher than C (or vice-versa) rather than seeing that they were in fact equal.
But for those in favour of Standard Ranking I have raised an enhancement request (support task 154450) so that it may be implemented at some point in the future.
Incidently, if you are into Java coding then you might like to know that you can create your own Advanced Functions for Yellowfin, more about this in this other forum post.
regards,
Dave
yes it is deliberate, at the time of implementing this function our major clients were asked which they preferred and they all went for dense ranking.
I guess the problem with standard ranking is that if 2 rows are equal in rank then how should it be decided which of 2 equal rows gets the higher ranking. In the above Wikipedia example you would have to decide whether B should be given the rank of 2 and C the rank of 3, or the other way around. Then if a user gave a quick glance at the report they might erroneously assume that B was higher than C (or vice-versa) rather than seeing that they were in fact equal.
But for those in favour of Standard Ranking I have raised an enhancement request (support task 154450) so that it may be implemented at some point in the future.
Incidently, if you are into Java coding then you might like to know that you can create your own Advanced Functions for Yellowfin, more about this in this other forum post.
regards,
Dave
Thanks David,
My understanding of standard ranking (according to the page I quoted) is that if two numbers are the same they get the same rank, but the number that would have been used is skipped.
i.e.
A 1st
B 2nd
C 2nd
D 4th
Which is the ranking system I would like included in the feature request if it goes ahead.
Cheers =)
My understanding of standard ranking (according to the page I quoted) is that if two numbers are the same they get the same rank, but the number that would have been used is skipped.
i.e.
A 1st
B 2nd
C 2nd
D 4th
Which is the ranking system I would like included in the feature request if it goes ahead.
Cheers =)
Hi Max,
OK I've added that example to the support task so it is clear what you are after.
regards,
Dave
OK I've added that example to the support task so it is clear what you are after.
regards,
Dave