Researchers say they have found that fatness can spread from person to person in social groups. When one person gains weight, close friends often gain weight, too. 

The researchers looked at records from the Framingham Heart Study. It gathered health information about more than 12,000 people from 1971 to 2003. 

The study shows that when a person becomes severely overweight, there is a 57 percent increased chance that one of their friends will be, too. A sister or brother of the overweight person has a 40 percent increased chance of becoming fat. The increased risk for a wife or husband is a little less than that. 

Nicholas Christakis, lead investigator of the study, says his research shows that fat people are not choosing fat friends. He says there is a direct causal relationship between a person getting fat and being followed in weight gain by a friend. 

The study finds that the sex of the friends is also an influence. In same-sex friendships, a person has a 71 percent increased risk of getting fat. The same is true for brothers and sisters separately. A man has a 44 percent increased risk of becoming obese after a weight gain in his brother. In sisters, the increased risk is 67 percent. 

The study also shows that physical closeness of family members and friends do little to increase a person's risk.James Fowler, the other lead investigator, says a friend who lives a few hundred kilometers away has as much influence as one in your neighborhood. He says the study demonstrates the need to consider that a major part of a person's health is tied to his or her social connections.

 Doctor Christakis and Mister Fowler say close friends probably influence what a person finds acceptable and unacceptable. So if a friend gets fat, the condition becomes more acceptable. Both investigators agree their research shows that obesity is not just a private medical issue, but a public health problem. 

1. According to the study, the __ of an overweight person is the most likely to gain weight. 

A) The booming growth of Al is both exciting and scary. It's exciting to consider all the ways our lives may improve,from managing our calendars to making medical diagnoses, but it's scary to consider the social and personal implications——and particularly the implications for our careers. As machine learning continues to grow, we all need to develop new skills in order to differentiate ourselves. But which ones? 

B) It's long been known that Al and robotics will change markets and workforces. Self-driving cars will force over three thousand truck drivers to seek new forms of employment, and robotic production lines like Tesla's will continue to eat away at manufacturing jobs. But this is just the beginning of the disruption. As Al improves, a much broader set of jobs will be affected. We' re talking about jobs like teacher, doctor, financial advisor, marketer, and business consultant——jobs that we can't imagine being done without the participation of a human being. 

C) There are just a lot of things that machines can do better than human beings. Many skilled jobs follow the same general workflow: gathering data, analyzing the data, interpreting the results, determining a recommended course of action, and implementing the course of action. Doctors, for example, perform tests, analyze the results,interpret the results to make a diagnosis, plan a course of treatment, and then work with the patient to make this treatment plan a reality. Financial advisers gather and analyze data about their clients and potential investment vehicles, interpret the implications given a variety of factors such as risk tolerance, recommend an investment strategy, and help their clients carry this strategy out over time. 

D) We' ve accepted that machines can do tasks like data gathering and analysis more efficiently than human beings.However, their potential goes much further. Human beings are limited, and often biased. Doctors will never be able to keep up with every new publication in their areas of expertise. Instead, they must rely on a small number of personal experiences rather than the complete knowledge in their field. Consultants, too, can only experience so many company transformations over their careers. From a narrow set of experiences, they form their preferences,expectations, and insights. Human beings must rely on their own, often biased, preferences, habits, and rules of thumb. 

E) Some people may say that we will never trust machines with important decisions such as the management of our health and money, but this is twentieth century thinking. IBM's Watson is already capable of st oring far more medical information than doctors and making evidence-based decisions that are free of cognitive biases, and investors are fleeing expensive, actively managed funds for better-performing passive ones. The value of some of our most prized career paths is already being undermined. 

F) Those that want to stay relevant in their professions will need to focus on skills and capabilities that artificial intelligence has trouble replicating——understanding, motivating, and interacting with human beings. A smart machine might be able to diagnose an illness and even recommend treatment better than a doctor. It takes a person, however, to sit with a patient, understand their life situation (finances, family, quality of life, etc.), and helpdetermine what treatment plan is optimal. 

G) Similarly, a smart machine may be able to diagnose complex business problems and recommend actions to improve an organization. A human being, however, is still best suited to jobs like spurring the leadership team to action, avoiding political hot buttons, and identifying savvy（有见识的人）individuals to lead change. 

H) It's these human capabilities that will become more and more prized over the next decade. Skills like persuasion,social understanding, and empathy are going to become differentiators as artificial intelligence and machine learning take over our other tasks. Unfortunately, these human-oriented skills have been viewed as second priority in terms of training and education. We' ve all experienced the doctor, financial planner, or consultant who is more focused on his or her reports and data than on our unique situations and desires. 

I) For better or worse, these skills will become essential to anyone who wants to stay relevant in their field as automated systems proliferate. We have three recommendations: 

J) Don't fight the progress of technology. Machine learning and AI have the ability to improve outcomes and lower cost. Welcome the change in your industry and work to make it fruitful and complementary. 

K) Examine your own capabilities interacting with, motivating, and assessing people. Recognize your strengths and weaknesses when it comes to emotional intelligence. 

L) Invest in developing your emotional intelligence. Focus on how you can better manage, influence, and relate to others. Or, take it a step further by seeking out training and stretch opportunities. 

M) What you have to offer——what you can do better than any smart machine——is related to the people around you. Begin to nurture and invest in these abilities the same way that you have the more technical parts of your career. If you can be an outstanding motivator, manager, or listener, then you will still have a part to play as technology changes your industry. 

1) It's beyond our imagination that jobs like teacher can be done without a real human being.  

2) A human doctor needs to communicate with patients to make the best treatment plan for them.  

3) It's impossible for doctors to keep up with every new development in their field.   

4) Interpersonal skills have not been given top priority in training and education.  

5) Watson can apply its vast stores of medical knowledge to actual decision-making.