Many fundraisers ask for donations using e-mail and text messages. The paper "Now or Never! The Effect of Deadlines on Charitabl
e Giving: Evidence From Two Natural Field Experiments" ( Journal of Behavioral and Experimental Economics [2016]: 1-10) describes an experiment to investigate whether the proportion of people who make a donation when asked for a donation by e-mail is different from the proportion of people who make a donation when asked for a donation in a text message. In this experiment, 1.32% of those who received and opened an e-mail request for a donation and 7.77% of those who received a text message asking for a donation actually made a donation. Assume that the people who received these requests were randomly assigned to one of the two groups (e-mail or text message) and suppose that the given percentages are based on sample sizes of 2000 (the actual sample sizes in the experiment were much larger). a. The study described is an experiment with two treatments. What are the two treatments?
b. Use a 90% confidence interval to estimate the difference in the proportions who donate for the two different treatments
c. Is there convincing evidence that the proportion who make a donation is not the same for the two different methods? Carry out a hypothesis test using a significance level of 0.05.
d. Is there convincing evidence that the proportion who make a donation after receiving an email is smaller than the proportion who make a donation after receiving a text message? Carry out a hypothesis test using a significance level of 0.10.