Results of a 2015 Contact Solutions study reveal insights on perceptions and attitudes toward mobile shopping, providing direction to retailers for developing strategies for investing their dollars in the mobile app experience. Increased consumer interest in using shopping applications means retailers must adapt to meet the rising expectations for specialized mobile shopping experiences.

The study results show that 23% of consumers indicate that in-app recommendations would drive them to add more items to their cart and that 33% would spend more time in the app. But shopper priorities change the moment they need help; they expect to get it immediately and effortlessly. If forced to stop what they're doing and leave the app to get help, 1 out of 4 shoppers would likely not make a purchase with the brand at all. The research is based on an online survey with a sample of 1,600 US adults who have made purchases via their mobile device.

a. Describe the population of interest.

b. Describe the sample that was collected.

c. Describe a parameter of interest.

d. Describe the statistic used to estimate the parameter in (c).