"visualize .ass and GSP error"

olandesino

Hi,
I'm a beginner data miner, hope that someone still can help me.

1. How can I visualize outputs from learners, example how can visualize W-Apriori output (.ass)?

2. When i use GSP algorithm and appears GeneralizedSequentialPatterns: Cannot handle missing values!
i don't understad because there are absolute no missing values in my data set, i tried even with preprocessing missing value operation. How can I solve this problem?

Thanks in advance

A.Florio

olandesino

Am I in the wrong forum?.. ???

haddock

Hi,

In short you probably are in the wrong place for good answers to your questions, as both of your questions relate to WEKA operators. However, missing values are there if the learner says so, so if you are certain there are no missing values you will need to understand why the learner doesn't like the input example set. What exactly have you done to check the values?

olandesino

thanks for the advice, i'll be more careful next time.
By the way, i check personally all 385 rows of my dataset and it says the cannot handle missing values.
Besides i putted also the MissingValueReplenishment operator.

This is the simple process

<operator name="Root" class="Process" expanded="yes">
    <operator name="ExampleSource" class="ExampleSource">
        <parameter key="attributes" value="~/dataset.aml"/>
    </operator>
    <operator name="MissingValueReplenishment" class="MissingValueReplenishment">
        <list key="columns">
        </list>
    </operator>
    <operator name="W-GeneralizedSequentialPatterns" class="W-GeneralizedSequentialPatterns">
    </operator>
</operator>

I really appreciate your help.
Thanks
A.Florio

haddock

Okidokey, let's walk it through. If you right click on the example source operator, insert a "break after", and then run the process, what then do you see in the examples? In RM the '?' indicates a missing value.

By the way, the missing value operator is currently set to do nothing, but we can come to that later.

olandesino

Hi,

I run the process till the example source(break) and the output window shows me the data (385 rows and 3 regular attributes) in 3 ways (Meta data, data and plot). Even here there are no missing values or '?'. :-\

haddock

Mmm, the view to look at is the data view. You will see a view filter there that can highlight missing attributes and labels, I take it that all is well, and there are no '?''s there?

If so we have to think again, as the missing value fixer won't help. In that case I think you'd be better off to check with WEKA on the input formats required, perhaps that is being read wrongly. I trust that you put all the right things in you AML file but I'm not familiar with this operator so I can't tell, sorry.

I have noticed that you can turn up the debug level on this operator, and of course you can do the same with RM; that might point you to what is clogging the system.

olandesino

Thanks a lot for your help.
I hope there is (somewhere) a solution for this problem.

A.Florio