Weka - How to remove an attribute whose all values are missing?
I have a CSV file containing data for a market-basket analysis. I have imported the file successfully to Weka, but I found that some attributes does not have any value, i.e., all values are missing. Weka don't let me use the Apriori algorithm with this data, so I would like to know if there is a way to remove those attributes from the imported data.
PS.: There are thousands of attributes, so I don't want to specify the attributes that need to be removed.
Answer
You can remove them using the "remove" filter in WEKA's Explorer. Once the data has been loaded into WEKA:
1) Go to "Process" (1st main tab).
2) In "filter" area click "Choose" a filter.
3) Navigate through the tree to "filters" -> "unsupervised" -> "attribute" -> "Remove".
4) Once "Remove" filter has been chosen, click to "Remove" label next to "Choose" button, it will open a dialog.
5) Fill out the attributeIndices text field with the index/indices of the attributes to be removed, i.e. "1,4,10" or "1-3,7".
6) Click "OK" in the dialog and "Apply" button in the filter area of the main window.
That's all !!