Nowadays people are troubled by the violence that spreads throughout the media. Movies, te

Nowadays people are troubled by the violence that spreads throughout the media. Movies, television and video games are full of gunplay and bloodshed, and one might reasonably ask what’s wrong with a society that presents videos of violence as entertainment.
Viewing large amounts of violent television and video games may well contribute to violent behavior in certain individuals. The trouble es when researchers downplay uncertainties in their studies or overstate the case for causality（因果关系）. Skeptics were dismayed several years ago when a group of societies including the American Medical Association tried to end the debate by issuing a joint statement: “At this time, well over 1,000 studies… point to a causal connection between media violence and aggressive behavior in some children.”
Freedom-of-speech advocates accused the societies of catering to politicians, and even disputed the number of studies (most were review articles and essays, they said). When Jonathan Freedman, a social psychologist at the University of Toronto, reviewed the literature, he found only 200 or so studies of television-watching and aggression. And when he weeded out “the most doubtful measures of aggression”, only 28% supported a connection.
The critical point here is causality. The alarmists say they have proved that violent media cause aggression. But the assumptions behind their observations need to be examined. When labeling games as violent or non-violent, should a hero eating a ghost really be counted as a violent event? And when experimenters record the time it takes game players to read “aggressive” or “non-aggressive” words from a list, can we be sure what they are actually measuring? The intention of the new Harvard Center on Media and Child Health to collect and standardize studies of media violence in order to pare their methodologies, assumptions and conclusions is an important step in the right direction.
Another appropriate step would be to tone down the criticism until we know more. Several researchers write, speak and testify quite a lot on the threat posed by violence in the media. That is, of course, their privilege. But when doing so, they often e out with statements that the matter has now been settled, drawing criticism from colleagues. In response, the alarmists accuse critics and news reporters of being deceived by the entertainment industry. Such clashes help neither science nor society.
46. Why is there so much violence shown in movies, TV and video games?
A. Showing violence is thought to be entertaining.
B. Something has gone wrong with today’s society
C. Many people are fond of gunplay and bloodshed.
D. There is a lot of violence in the real world today.
47. What is the skeptics’ view of media violence?
A. Violence on television is fairly accurate reflection of real-world life.
B. Most studies exaggerate(夸大) the effect of media violence on the viewers.
C. A causal relationship exists between media and real-world violence.
D. The influence of media violence on children has been underestimated.
48. The author uses the term “alarmists” to refer to those who     .
A. use standardized measurements in the studies of media violence
B. initiated the debate over the influence of violent media on reality
C. insist on a direct link between violent media and aggressive behavior
D. use appropriate methodology in examining aggressive behavior
49. The underlined phrase “weeded out” in Paragraph 3 most probably means     .
A. got rid of things that are not good     B. removed unwanted parts from something
C. picked out things that are useful           D. took away unnecessary details of a report
50. What does the writer think of the debate concerning the relationship between the media and violence?
A. He more than agrees with the views held by the alarmists. 
B. It should e to an end since the matter has now been settled.
C. The past studies in this field have proved to be misleading.
D. More studies should be conducted before conclusions are drawn.A