st: RE: Dropping Observations based on Observations Across Rows

[Beatrice Benavidez <beatricestata1711@gmail.com>]

Hi all,

I have this example subset of a dataset:
Date ID Description
1/1    1        Purchase
1/1    1          Refund
1/1    2        Purchase
1/1    2          Refund
1/1    3        Purchase
1/1    4        Purchase
2/2    1        Purchase
2/2    2        Purchase
2/2    3        Purchase
2/2    3          Refund
2/2    4        Purchase
2/2    4          Refund

For a particular date and ID, there is a description variable where I
have Purchase and Refund
I would like for the one particular date and ID to then drop those
observations completely where there are both Purchase and Refund
counterparts in the subset dataset.

I would then like my subset dataset to be reduced to:
Date ID Description
1/1    3        Purchase
1/1    4        Purchase
2/2    1        Purchase
2/2    2        Purchase

How will I go about doing this.

Thank you so much!

Kind regards,


Beatrice
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