Hi everybody,
I am new to Qualtrics. I am glad to see that there is a huge community here. Thanks a lot for any advice you may have for me! For our first project, we need two fairly simple tables. However, I seem to be unable to create them in Qualtrics.
 
Table 1:
The idea is that a participant has to choose one out of two options, e.g., left-hand side or right-hand side, for a list of ten categories (product 1, product 2, ...). Here, the participant can only choose one out of the two and has to choose one for each category. So far, so simple and easy to create with Matrix table, Bipolar, 2 Scale points, 2 Labels, Force response. However, I also need a validation: Namely, the first time the left-hand side is chosen all the following answers have to be left-hand side as well. I tried using the count function, I am completely lost. Is such a validation possible?

______________Left-hand side______Right-hand side________________________
Product 1_________]_______________________]__________Alternative product 1
Product 2_________]_______________________]__________Alternative product 2
Product 3_________]_______________________]__________Alternative product 3

Examples:
Valid: Right-hand side, Right-hand side, Left-hand side.
Valid: Right-hand side, Left-hand side, Left-hand side.
Not valid: Right-hand side, Left-hand side, Right-hand side.
Not valid: Left-hand side, Right-hand side, Right-hand side.

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Table 2:
With the second table I am struggling even more: Here, we have a similar structure. However, the participant has to choose one category (line), but cannot choose zero, two, or more. It seems to me that Matrix table with Bipolar is not accepting multiple choice (to be able to unselect an item here). A Matrix table with Likert accepts multiple choice, but I am unable to have a text left and right from the item and I am unsure about the custom validation. Do you have any ideas on how I can create this table and write the custom validation?

______________Left from here_____________________
Product 1___________]_________Alternative product 1
Product 2___________]_________Alternative product 2
Product 3___________]_________Alternative product 3

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Thank you very much! Any help is much appreciated.