A poll conducted in the US found that people vaccinated against Covid-19 were less comfortable than unvaccinated people toward a variety of public activities.

a)Based on this data ,can you conclude that being vaccinated reduces people's likelihood in engaging in public activities? Explain.(1 mark)

b)Suppose you are interested in establishing the causal link between being vaccinated and people's likelihood to return to normal activities in a Covid effected country like the US or the UK. Describe how you might be able to use any two of the four empirical methods (randomised experiment, instrumental variable, difference-in-differences, regression discontinuity) presented in the lectures for this purpose. For each method, describe the data you would need and discuss the potential limitations/challenges of applying that method.(4 marks)

Adults Who Have Not Been Vaccinated for COVID-l9 More Likely Than Vaccinated Adults to Express Comfort Toward a Variety of Public Activities Share of vaccinated' and unvacclnated US. adults who said they would be comfortable doing each of the following activities right now given the state of the coronavirus pandemic: Going on a cruise Attending a concert Attending a work conference Traveling abroad Visiting an amusement park Going to the gym Attending a sporting event