I need to do an experiment. First let me describe present situation. The company that I work for is a cinema. It has a gaming section where people who are waiting for movies can pass time by playing games. People can pay only by using prepaid membership card. Unfortunately this gaming section is not generating enough sales. We are trying to find the cause(s).
My hypothesis is if we accept cash as payment, sales will increase.
My plan is to have experimental group and control group. The experimental group will accept cash payment, the control group doesn't. The sales of both groups are tallied before and after the experiment.
The difficult thing about this is that I can't find a way to isolate the 'cash payment' factor from other factors:
- When the movie playing in the cinema is good, more people will come and sales will also increase
- Each cinema only has one gaming section, I can't split it into two sections (one accepts cash, the other doesn't)
- If several sites accept cash and several others don't, I don't think I can compare the results directly because the visitors are different, the number of gaming units are different
I'm looking for suggestions to isolate this 'cash payment' variable, or maybe another approach altogether.