3. A researcher is collecting individual data by asking visitors in a train station in a medium sized town to fill in a questionnaire. It takes nearly 30 minutes to complete the survey questions. To encourage higher participation rate, the researcher provides a small financial incentive that is enough to buy a sandwich. The researcher wants to use this sample to make predictions about effect of using social media on health among the residents of the town. a. Explain the random sampling assumption, that is one of the Gauss-Markov assumptions for linear regressions. [5 marks] b. Do you think this assumption is satisfied in the sample collected by the researcher? Explain your answer in no more than 85 words. [5 marks] c. What are the possible consequences of violation of random sampling assumption for predictions based on this sample? Explain your answer in no more than 85 words [5 marks] 3. A researcher is collecting individual data by asking visitors in a train station in a medium sized town to fill in a questionnaire. It takes nearly 30 minutes to complete the survey questions. To encourage higher participation rate, the researcher provides a small financial incentive that is enough to buy a sandwich. The researcher wants to use this sample to make predictions about effect of using social media on health among the residents of the town. a. Explain the random sampling assumption, that is one of the Gauss-Markov assumptions for linear regressions. [5 marks] b. Do you think this assumption is satisfied in the sample collected by the researcher? Explain your answer in no more than 85 words. [5 marks] c. What are the possible consequences of violation of random sampling assumption for predictions based on this sample? Explain your answer in no more than 85 words [5 marks]