求问新prep CR的第98题~不明白答案~

liaoyuan614

98.The violent crime rate (number of violent crimes per 1,000 residents) in Meadowbrook is 60 percent higher now than it was four years ago.  The corresponding increase for Parkdale is only 10 percent.  These figures support the conclusion that residents of Meadowbrook are more likely to become victims of violent crime than are residents of Parkdale.
The argument above is flawed because it fails to take into account

A. changes in the population density of both Parkdale and Meadowbrook over the past four years
B. how the rate of population growth in Meadowbrook over the past four years compares to the corresponding rate for Parkdale
C. the ratio of violent to nonviolent crimes committed during the past four years in Meadowbrook and Parkdale
D. the violent crime rates in Meadowbrook and Parkdale four years ago
E. how Meadowbrook's expenditures for crime prevention over the past four years compare to Parkdale's expenditures

我选的是B，答案是D。为什么要选D呢？把四年前两国的犯罪率考虑进去就可以判断which country's citizen is more likely to become the victim of crime? 之间的逻辑在哪里呢？感谢各位！

wjtwenzi

楼主，其实这是一个基数和涨率的问题。
M市犯罪率如果四年前是10%，P市是80%（当然这比较极端啊~）那么现在M市涨了60%P市涨了10%，仍然是M市比P市低啊。涨的多不代表结果就高，原文就是没有把基数交代清楚，所以flaw了
至于B，人口增长是一个不相关因素~
楼主可以看看Prep08语法笔记，里面有详细讲解~

liaoyuan614

wjtwenzi 发表于 2013-10-23 19:12
楼主，其实这是一个基数和涨率的问题。
M市犯罪率如果四年前是10%，P市是80%（当然这比较极端啊~）那么现在 ...

谢谢亲，prep08语法笔记里不是将SC的吗~只看完RC和CR，还没看语法，所以不太清楚哈~

wjtwenzi

liaoyuan614 发表于 2013-10-23 22:28
谢谢亲，prep08语法笔记里不是将SC的吗~只看完RC和CR，还没看语法，所以不太清楚哈~ ...

说漏了，Prep08笔记SC和CR都有了！
这是SC的：http://forum.chasedream.com/thread-484446-1-1.html
这是CR的：http://forum.chasedream.com/thread-839547-1-1.html

liaoyuan614

wjtwenzi 发表于 2013-10-23 23:17
说漏了，Prep08笔记SC和CR都有了！
这是SC的：http://forum.chasedream.com/thread-484446-1-1.html
这是 ...

谢谢亲~太好了~

suapplle

请问一下，是犯罪率高了，residents更容易受侵犯还是犯罪的数量多了，更容易受侵犯呢？纠结了好久，求教～

potentialwjy117

除了要考虑以前的犯罪比率,我觉得还要考虑人口总数..且两者缺一不可

接着楼上的例子:
M市从10%涨了60% -->0.1*1.6
P市从80%涨了10%  --> 0.8*1.1

如果M市有100,000,000人口
P市有1,000人口

虽然M市犯罪率比P市低很多,但犯罪数要多了不少,因此也会导致
the conclusion that residents of Meadowbrook are more likely to become victims of violent crime than are residents of Parkdale.

凤梨酥

wjtwenzi 发表于 2013-10-23 23:17
说漏了，Prep08笔记SC和CR都有了！
这是SC的：http://forum.chasedream.com/thread-484446-1-1.html
这是 ...

楼主简直大好人  感觉打开了新天地