topic Re: How to preserve Cluster numbers while using pro fastclust in SAS Procedures

How to preserve Cluster numbers while using pro fastclust

ehsanmath — Fri, 10 Jun 2016 12:44:26 GMT

Hallo,

I am facing a issue with proc fastclust. I want to have 5 clusters and I can get them very well. The problem is: If I run the same procedure on two different datasets which has actually the same data, I get different numbers for clusters although the behaviour clousters are the same.

For example:

A cluster, which was numbered 2 in first run, is numbered 3 in the second run. Using Profiling I can see the fact that cluster 2 in first run is equivalent to cluster 3 in second run.

Do any one has Idea how I can preserve the cluster numbers ?

Thanks in advance

Ehsan

Re: How to preserve Cluster numbers while using pro fastclust

Kurt_Bremser — Fri, 10 Jun 2016 13:00:08 GMT

Do the datasets have the same order?

Re: How to preserve Cluster numbers while using pro fastclust

Rick_SAS — Fri, 10 Jun 2016 14:36:57 GMT

If the clustering is really the same, then you can do the following:

1. From the first run you can use the OUTSTAT= option to output the centers. Call the centers

CA_1, CA_2, .., CA_k.

2. From the second run you can use the OUTSTAT= option to output the centers. Call the centers

CB_1, CB_2,..., CB_k.

3. Concatenate the centers into a single data set and use PROC DISTANCE to compute the distance between centers.

4. The first k columns and the last k rows represent the distance between the centers in each run. The smallest elemtn in each column tells you which center in Run A mathch up with which cetners in Run B.

Re: How to preserve Cluster numbers while using pro fastclust

ehsanmath — Fri, 10 Jun 2016 15:20:33 GMT

Actually, order does not matter here. What really matters is the "time period". I have one dataset from May2016 and the second Dataset from Jun 2016. Since the (customer) data comes from the same source. Also the experiementation shows that I can always finde the same clusters but with different numbers.

Re: How to preserve Cluster numbers while using pro fastclust

ehsanmath — Sat, 11 Jun 2016 15:01:01 GMT

Thanks It seems to work 🙂