Why won't Weka allow me to start Association Rule generation?

I have created an arff file for a data set that I would like to use in Weka. The file is formatted as a sparse arff file. Anyway, I have successfully loaded in the data. I then switch to the Association tab and set my parameters. However, the Start button won't become enabled, so I can't click it to start the开发者_开发问答 association generation. Why is this? Has anyone run into this issue before and know how to solve it?

Here is a screenshot:

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all variables must be Nominal; is the a priori method does not work on numeric variables

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You may want to check the attribute types in your arff file. Weka is very particular about types when they are used for associations and even though it may let you set parameters, the routine will not run.

Try using an attribute declaration like the following:

@attribute "attr1" {t}

And define your rows as follows:

{1957 "t", 9163 "t", 10143 "t"}