I got a question regarding the binomial distribution and testing for significance in general.
I need to divide a dataset into a treatment group (with phone call) and a control group (no phone call). My boss told me I need to divide it based on significance tests. However, I told him that's not possible if no one has been called yet, since I have no data to work with now (what is the success rate? what is the number of successes?).
The question is: First, am I wrong for thinking that this request with the signficance tests is not possible? Second, how would I divide the control and treatment group in a logical way? I was thinking about 90/10 since I have a limited sample size, but I have no way of supporting my choice other than this.