Hey there,

I have panel data based on a salomon four group design (4 groups):
1. treatment and pre/posttest scores
2. treatment and posttest scores
3. controll group and pre/posttest scores
4. controll group and posttest

I want to do 2 regressions in order to find out if the treatment had an effect on the order frequency and order sum. My data set has the following variables:
  • CustomerID
  • Treatment (Dummy Variable)
  • Pretest (Dummy Variable)
  • Total Order Sum
  • AVG Order Sum
  • Amount Orders
  • AVG Order Frequency
  • AVG Order Volume (average of items per purchase)
  • Discounts
  • Returns

Do you have any advice which regression type to use or how to find out which regression type is appropriate? Because of the Solomon Four Group Design I'm really struggling with the regression equation.


Thank you so much!

Sophie