The operation team of a retailer is about to report the performance of year 2022. As the data analyst, your job entails reviewing the reports provided by the team. One of the reports regarding membership subscription looks suspicous to you. In this report, they compared the amount of money spent by the members against the non-members over the year. The methodology is that they randomly selected 20 customers and compared their spending before and after becoming a member.
The average spending before becoming a member is $88.5 per week with a standard deviation of $11.2 . The average after becoming a member is $105 per week with a standard deviation of $15. In the report, the retailer claimed that after becoming a member, customers tend to spend 10% more than before on average.
As a statistician, you decide to perform a hypothesis test to verify the veracity of this claim. State your hypothesis, perform the test and interpret the result. Additionally, please suggest another methodology to compare member vs non-member.
