DSC5104 – Assignment 2 Obesity & Social Networks Notes: 1. Try to answer the questions as precisely as possible. You should take no more than 2 pages (i.e. 1 sheet of paper) for this assignment. 2. Please upload the assignment document in PDF and mention your name and ID inside the document. 4. Submit on or before Mar 27th (Fri) 11.59pm. Problem context: Certain research studies have claimed that obesity can spread through social networks, much like how viruses spread. The authors of the study emphasize that if a person becomes obese, friends of the person are also likely to get obese in due time. For instance, in a popular study published by the New England Journal of Medicine, the authors presented a detailed analysis of a large social network of 12,067 people to show that when a person got obese, it increased the chances of the persons’ friends becoming obese by more than 50%. For more details on the study and related press coverage please refer to the links below. Interestingly, the effect of the contagion was not limited to friends alone. The study also found that among adult siblings, if one of the siblings became obese, it increased the chances of obesity of the other by 40%. Similarly, if a spouse became obese, it increased the chances of the other spouse becoming obese by more than 30%. No such effect, however, was observed for neighbors. Reference Links: https://www.nytimes.com/2007/07/25/health/25cnd-fat.html Study: https://www.nejm.org/doi/full/10.1056/NEJMsa066082 Questions: 1. Do you believe the key findings of this study? More specifically, which finding(s) from the study do you think is more likely/less likely to be true for a general population? (2 marks) 2. What are 2-3 limitations of the given study? You can include any limitations related to the formulation of the research questions, study design, quality of data, analysis of results, and interpretation of findings. (3 marks) 3. What are some general methodological challenges (not limited to the ones specific to this study) associated with assessing peer influence in networks? (2 marks) 4. If you had to answer the same question raised in the study (i.e. does obesity spread through a social network?), how would you design a study to answer this question (e.g. conduct a randomized lab/field experiment, analyze a specific type of historical dataset etc.)? (3 marks)
