question 26

In website development, there is a phenomenon known as the "novelty effect" where users of a website interact with a new website feature (such as a newly launched chatbot) simply because the feature is new and interesting, rather than because the new feature actually improves the overall experience of using the website. If the novelty effect is present, users will interact with the new feature less and less as the months progress. Assume the variable of interest is number of times someone interacts with the new website feature. What experimental design would you pick in order to determine if the novelty effect is present in the new feature? Select one: O B. A block design where blocks are defined by the browsers of the individual users (assume Safari, Firefox, and Chrome are the only choices). For each block, randomize 250 users to the website version with the new feature, and 250 other users to the original website. O b. A matched pairs design, where each experimental unit is an individual user. Randomly sample 1000 users from the website database and see how frequently they interact with the new website feature. A few months later, check how frequently each of these 1000 users interact with the now website feature. For each user, compare how frequently they interacted with the new website at the beginning, versus a few months later. . c. A stratified random sample, where the strata are two different time periods. The first time period is right when the new feature is launched, and the second time period is a few months later. At each time period, randomly sample 500 users and record the average number of times the users interact with the new feature for each group . d. A completely randomized design, where the treatment is the new feature, and the control is the original website without the new feature. Randomize 500 users to the website with the new feature, and randomize 500 other users to the original website