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Decision Tree Troubleshooting

5 - Atom

Hi all,


I am new to the Decision Tree tool within Alteryx, but i'm looking to build a predictive model for a binary target variable; whether someone will buy a ticket or not. 


I've tried a few variations of the model and I keep getting these error messages: 


Decision Tree Error.PNG


I think the latter errors may be due to the field type (I am currently inputting Gender and EmailOptIn - both binary variables - as strings) but I cannot fathom the "dim(x) must have a positive length" 


Any help would be great! 

Alteryx Certified Partner
Alteryx Certified Partner

Do you have any null or negative values in any of the variables being used in the model?


To check this quickly you can use the 'field summary' tool which allows you to get a quick overview regarding the contents of a field, including the min value, the max value, the number of missing values and so on.


I'm not sure the data type should be an issue as they have been accepted as a variable by the model tool.



5 - Atom

Hi Ben, 


Thanks for the reply. I can confirm that neither of the two variables have null or negative values; I have built a logistic regression model in the same workflow and used the Cleanse tool to convert any nulls into zero's where applicable. The Decision Tree tool is connected to output of the Data Cleanse tool; I dont know if thats interfering at all: 


Decision Tree Error v2.PNG


The two fields in question are both merely binary FYI (e.g. 1 = Male, 0 = Female for Gender).


Thanks, Henry