st: reshape from wide to long form

[Shehzad Ali <drshehzad_ali@yahoo.com>]

Hi listers,

I would really appreciate some help with data structuring/reshaping.

I want to change my data structure from wide to long form. The data comes from a discrete choice experiment. Each individual is given 6 choice sets. Each choice set has two options, A or B, and the individual is asked to choose between the two options for each choice set. The data currently looks like this:

id    choice_in_set1    choice_in_set2    choice_in_set3    choice_in_set4    choice_in_set5    choice_in_set6
1            A                        B                          A                        A                      B                        B
2            B                        B                          A                        B                      A                        B

I want the data to look like this:

id    choice_set    alternative    chosen (yes/no)
1            1                A                    1
1            1                B                    0
1            2                A                    0
1            2                B                    1
1            3                A                    1
1            3                B                    0
..
..
2            1                A                    0
2            1                B                    1
2            2                A                    0
2            2                B                    1
...
...

Any help would be greatly appreciated.
Many thanks,
Shehzad


      

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