excel data mining add-in for categorical data

Hi my friends,

I do have a problem with results of clustering algorithm with my categorical data.
In reality I have a big table with one's and zero's and I try to cluster according to 60 attributes.
I tries to cluster to two categories many times but I get only one cluster. What do you suggest. Which values can I change to the algorithm? Is there anything particular for categorical data ?

Thank for your help in advance.

Manolis

First, check Properties of your clustering model then AlgorithmParameters ->Set algorithm parameter; look at CLUSTER_COUNT parameter- it define the number of cluster in model- default is 10, maybe it has value 1.

Second explain the significance of your data with a set o sample so we can make a suggest.

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The way the cluster algorithm works is it starts from a semi-random starting point (it uses the data distributions and randomly jitters them) using the number of clusters you choose (or the number of auto-detected clusters). If, during the clustering operation, two clusters are coincident, it merges the clusters and creates a new randomized starting point. Of course, this can end up coincident with another cluster as well. In the end, any remaining coincident clusters are merged.

I could imagine a scenario where the data is distributed such that a probabilistic model of two clusters always results in merging, yet a model of more clusters could produce an interesting model. So one thing to try would be to increase the number of clusters to see what you have.

Another option is to not use the default probabilistic clustering method and switch to K-means. You will not be able to access this parameter through the Table Analysis Tool "Detect Categories" button or the simple "Cluster" button on the DM ribbon. You need to use the advanced "Create Model Manually" option where you explicitly select an algorithm and there's a button for parameters. The appropriate parameter is "CLUSTERING_METHOD".

HTH

-Jamie

excel data mining add-in for categorical data

Thank you very much for your previous answers conserning clustering algorithm.

I change a bit my data and now I can get two and three clusters as I wish.

But now I have a different question. I wish to keep my Structure and Model for further trials with different algorithm values, like cardinality. I tried the following

I selected in excel Data Mining and then the option cluster button.

Then in the cluster wizard I chose analysis service data source and I reform the query as I need adding only at the end

where "STAFF_YES" = 1. Then I choose the needed columns and target value. Finally I select browse model, enable drill through only and I finish the wizard and get some results, rather good. But i need to try again with different parameters.

I tried Business intelligent Studio to check my Analysis service. The structure were here but when I changed any parameter and I tried to reprocess I got the following messages

Processing Mining Structure 'try Structure_1' completed successfully.
Start time: 5/8/2007 4:55:08 μμ; End time: 5/8/2007 4:55:08 μμ; Duration: 0:00:00
Processing Dimension 'try Structure_1 ~MC-__RowIndex' completed successfully.
Start time: 5/8/2007 4:55:08 μμ; End time: 5/8/2007 4:55:08 μμ; Duration: 0:00:00
Processing Dimension Attribute '(All)' completed successfully.
Start time: 5/8/2007 4:55:08 μμ; End time: 5/8/2007 4:55:08 μμ; Duration: 0:00:00
Processing Dimension Attribute 'EPI_CELL_SINO_GOOD' completed successfully.
Start time: 5/8/2007 4:55:08 μμ; End time: 5/8/2007 4:55:08 μμ; Duration: 0:00:00
Processing Dimension Attribute 'EPI_CELL_SINO_LOOSE' completed successfully.
Start time: 5/8/2007 4:55:08 μμ; End time: 5/8/2007 4:55:08 μμ; Duration: 0:00:00
Errors and Warnings from Response
Internal error: The operation terminated unsuccessfully.
Internal error: The operation terminated unsuccessfully.
Internal error: An unexpected error occurred (file 'pcprocbinding.cpp', line 6645, function 'PCDBProcBinding:electOrChangeCartridge').
Errors in the OLAP storage engine: An error occurred while the dimension, with the ID of 'try Structure_1 ~MC-__RowIndex', Name of 'try Structure_1 ~MC-__RowIndex' was being processed.
Errors in the OLAP storage engine: An error occurred while the 'EPI_CELL_SINO_LOOSE' attribute of the 'try Structure_1 ~MC-__RowIndex' dimension from the 'DMAddinsDB2' database was being processed.
Internal error: The operation terminated unsuccessfully.
Internal error: The operation terminated unsuccessfully.
Internal error: An unexpected error occurred (file 'pcprocbinding.cpp', line 6645, function 'PCDBProcBinding:electOrChangeCartridge').
Errors in the OLAP storage engine: An error occurred while the dimension, with the ID of 'try Structure_1 ~MC-__RowIndex', Name of 'try Structure_1 ~MC-__RowIndex' was being processed.
Errors in the OLAP storage engine: An error occurred while the 'EPI_CELL_SINO_GOOD' attribute of the 'try Structure_1 ~MC-__RowIndex' dimension from the 'DMAddinsDB2' database was being processed.

And no change to the structure take place.

Please help me if you can

Thank you in advnce

Best regards.

Manolis

We discovered this issue and it will be addressed in a future release but currently there is no workaround for this problem using BI Dev Studio.

Here is an alternate way of doing the same thing:

- in Excel, under the Data mining tab, select the "Advanced\Add model to mining structure" option

- create a new model using whatever algorithm (Clustering, I assume) and setting any parameters you might want.

The wizard will create a new model inside the same structure and process it.

If having multiple models does not bother your, you can leave them all inside the structure. Otherwise, you can delete the old models using the Manage Models option in the Data Mining tab.

Also, after executing the steps you mentioned in the BI Dev Studio, chances are that your mining structure is in an incosistent state. You can restore its original (processed) state by invoking, under Manage Models, Process structure with new data then point to the data source you used in creating the structure the first time

Hope this helps

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