[分享] 七宗罪都躲在CR題的哪裡

[danyuchn (Javy)]

很多自修版友都在問「CR」抓不到點怎麼辦？
但其實我認為，AWA大家背到爛的「七宗罪」應該要從AWA的束縛中解放出來。
AWA的七宗罪不是讓大家最後一刻拿來背的，這樣就浪費了它的邏輯價值了。
經過兩年的機經整理跟題目研究，其實有很多CR的思路，都是從七宗罪出發。
所以，若是各位CR抓不到點，可以開始先看這一份
「七宗罪都躲在CR的哪裡？」的筆記


下面是根據自己的回憶跟理解，打的一份幫助自修版友的筆記。
有些題目是JJ、有些題目是官方原文題目、有些題目則是回憶中曾出現的類似概念自創題
可能不能說是相當完整，但我只是希望給出一個自修版友做CR時思辨的方向。

歡迎無斷轉載。

----本文開始----


1.      時間先後不能視為因果/過度簡化（oversimpilification）

1-1 多見於調查、實驗題的削弱（通常是找他因或找因果倒反）：


ex. 吃蘋果的人普遍長壽。結論：是蘋果導致人們長壽。

削弱Ans：
- 吃蘋果的人都集中在華盛頓州，where 溫和的氣候有助於人體的健康。（另有他因）
- 有錢的人才吃得起蘋果，而有錢人有資格享受較好的醫療照顧。（另有他因）
- 人活到老的時候自然喜歡吃蘋果。（因果倒反）




ex. 1993年的菸害防治法實施禁止在室內吸菸後，1994年的民眾吸菸率就下降了。
結論：菸害防治法的確有效降低吸菸率。

削弱Ans：
- 1993年到1994年間，煙商將每包香煙大漲20%（另有他因）
- 1994年的吸菸率下降導致政府在1993年制定菸害防治法。（不合理，所以題目
已經有時間順序的不適合用因果倒反）




2.      以偏概全（反向也會考到：以全概偏）

2-1 在調查、實驗題：攻擊取樣偏誤

ex. 抽樣調查發現平均壽命有下降，結論：這個國家的平均年齡正在下降。

削弱Ans：
- 該調查主要在A城市抽樣，where衛生環境差。（sample bias）

2-2 在統計母個體題：avg/individual的差異、樣本分布

中國的人均所得約為一萬美金。而按照中國的平均消費水平，5000就能算得上衣食無虞。
結論：中國人民普遍衣食無虞。

削弱Ans：
- 人均所得分配不均，有錢人太有錢，大部分的人都只有2000美金。
- 上海人均所得50000美金，其他州人均所得500美金。
- 各城市消費水平不平均，在兩萬才算衣食無虞的北京上海，人均所得只有一萬，
在三千就能衣食無虞的貴州，人均所得也是一萬。。

2-3 以全概偏：也是攻擊分配不平均

ex.
Roland: The alarming fact is that 90 percent of the people in this country
now report that they know someone who is unemployed.

Sharon: But a normal, moderate level of unemployment is 5 percent, with one
out of 20 workers unemployed. So at any given time if a person knows approx.
50 workers, one or more will very likely be unemployed.

Sharon's argument relies on the assumption that _________ .

b) unemployment is not normally concentrated in geographically isolated
segments of populations

3.      錯誤類比

3-1 出現在題目寫法「A例推B例」：切斷類比

ex. 南韓跟中國簽自由貿易協定，結果飛黃騰達，我們簽了服貿也會飛黃騰達！

削弱Ans：
- 南韓的經濟體系自主性高不會被中國壓迫，而我國會。（切斷類比）
- 服貿跟中韓FTA內容不相同。（切斷類比）

ex.
Although the discount stores in Goreville’s central shopping district are
expected to close within five years as a result of competition from a
SpendLess discount department store that just opened, those locations will
not stay vacant for long. In the five years since the opening of Colson’s,
a nondiscount department store, a new store has opened at the location of
every store in the shopping district that closed because it could not compete
with Colson’s.

Which of the following, if true, most seriously weakens the argument?

B. Increasingly, the stores that have opened in the central shopping
district since Colson’s opened have been discount stores.

4. 全時對等（all things being equal）：今非昔比（客觀條件改變）

4-1 出現在有時間落差的題型：過去不代表現在 or 現在不代表過去
亦常見於解釋題。

ex.
兩年前SONY根據市場調查的偏好，發現消費者偏好功能多過於體積，
於是推出了功能多樣但較其他筆電龐大的的17吋筆電。結果銷量卻很慘淡。

解釋Ans：
- 兩年間消費者的習慣改變，偏好輕薄短小的電子產品勝過功能充足。（全時不對等）

ex. （JJ題）
某人想去馬航應徵，可是往年馬航的每年才開10個缺，
但每年應徵者都將近1000個，平均錄取率才1%，
於是他認為自己機會很低，決定打退堂鼓，今年不去應徵馬航。

削弱Ans：
- 這一年間馬航風評大幅滑落，求職者們不再偏好去馬航應徵。

4-2 出現在方案題（尤其是講到金錢的）：
動態平衡（供與需、成本與收入、數量與單價）
講到省成本->想到可能忽略損失的收入
講到賣的數量變多->想到單價可能因此變低。
講到供給增加->有可能需求同時也增加

以上，反之皆然。


ex. （JJ題）最近新出土2000枚金幣，根據現在的市價，一枚可以賣到100美金。
因此若全數賣出可以獲得200000美金。

削弱Ans：
- 大量的供給會使得市價下降。（客觀條件改變）

出現在方案題（尤其是講到金錢的）：
動態平衡（供與需、成本與收入、數量與單價）
講到省成本->想到可能忽略損失的收入
講到賣的數量變多->想到單價可能因此變低。
講到供給減少->可能需求也同時減少

ex. （省成本->可能也損失了收入）
將產品的包裝從塑膠改為紙張，可以節省成本，增加利潤。
因此公司決定如此改變包裝。

削弱Ans：
- 消費者不喜歡購買用紙張包裝的貨品。（客觀條件改變）

ex. （減少供給->需求有可能也變少）
某項過去熱銷每月5000件的產品，公司最近改成每月限量1000個，
預計在限量之後，產品的在市場上的流通價格會水漲船高。

削弱Ans：
- 現在消費者的熱潮已過，對該產品感興趣的顧客剩下原來的1/10。





5.      錯誤二分

5-1 個人印象，比較會出現在flaw in the reasoning/Boldface的兩人對談題中

ex.
名嘴A：根據調查，我國民眾都支持保護環境。候選人甲的政策是提振經濟，
所以候選人甲背離民意。

名嘴B：你的論點有錯，因為提振經濟不必然代表一定不會保護環境。





6.      資料可信度
多出現於講歷史、講挖掘考古判定年代的題型。

6-1 加強題中：資料準確無誤

Sviatovian is a medieval Moringian text whose author and exact date of
composition are unknown. However, the events in the life of Prince Sviatov
that the text describes occurred in 1165, and in the diagram of Sviatov's
family that accompanies the text his father, who died in 1167, is identified
as still living. Thus Sviatovin must have been written between 1165 and 1167,
 assuming that___________

(C) the diagram accurately represents the composition of Sviatov's
family at the time Sviatovin was written

6-2 假設/削弱題中：證據不會錯

科學家發現某地出土了一群人類骸骨與鐵製用具。
經過放射同位素測定，發現人類骸骨的年代大約為西元前五萬年。
因此，科學家認為人類五萬年前就會打造鐵製用具。

假設Ans：
- 鐵製用具不是後來居住在這邊的人留下的。
削弱Ans：
- 鐵製用具可能是後來居住在這邊的人留下的。






7.      錯誤前提
印象中幾乎沒有在單人敘述的題型中出現過。（因為我們不能質疑題目中的事實）
但卻常見於兩人對談的flaw in the reasoning題，一人攻擊另一人的斷言。

A：人民重視環保勝過發展經濟，而候選人A提出了完整的環保政策，因此我們該選他。
B：根據民調顯示，60%的人重視經濟不重視環保，而40%的人只重視環保不在乎經濟。
（攻擊A的斷言）
B：候選人A的環保政策，其實並不完整。
（攻擊A的斷言）


-----本文結束-----



-----附錄：七宗罪以及其中一個版本的模版句，請理解內容-----

第一宗罪 過度簡化
The author commits a fallacy of causal oversimplification.
The line of the reasoning is that because A occurred before B,
the former event is responsible for the latter. (The author
uses the positive correlation between A and B to establish
causality. However, the fact that A coincides with B does
not necessarily prove that A caused B.) But this is fallacious
reasoning unless other possible causal explanations have been
considered and ruled out. For example, perhaps C is the cause
of these events or perhaps B is caused by D.

第二宗罪 Insufficient-sample（取樣有問題）
The evidence the author provides is insufficient to support the
conclusion drawn from it. One example is logically unsounded to
establish a general conclusion (The statistics from only a few
recent years are not necessarily a good indicator of future trends),
unless it can be shown that A1 is representative of all A. It is
possible that.... In fact, in face of such limited evidence,
the conclusion that B is completely unwarranted.

第三宗罪: 錯誤類比 (based on a false analogy)
The argument rests on the assumption that A is analogous to B in
all respects. This assumption is weak, since although there are
points of comparison between A and B, there is much dissimilarity
as well. For example, A..., however, B.... Thus, it is likely much
more difficult for B to do....

第四宗罪 all things are equal （全時對等）
The author commits the fallacy of “all things are equal”. The
fact that happened two years ago is not a sound evidence to draw
a conclusion that.... The author assumes without justification
that the background conditions have remained the same at different
times or at different locations. However, it is not clear in this
 argument whether the current conditions at AA are the same as they
used to be two years ago. Thus it is impossible to conclude that....

第五宗罪 Either-Or choice （錯誤二分）
The author assumes that AA and BB are mutually exclusive alternatives
 and there is no room for a middle ground. However, the author provides
 no reason for imposing an either-or choice. Common sense tells us that
 adjusting both AA and BB might produce better results.

第六宗罪 survey is doubtful （資料可信度有問題）
The poll cited by the author is too vague to be informative. The claim
does not indicate who conducted the poll, who responded, or when, where
and how the poll was conducted. (Lacking information about the number
of people surveyed and the number of respondents, it is impossible to
access the validity of the results. For example, if 200 persons were
surveyed but only 2 responded, the conclusion that...would be highly
suspect. Because the argument offers no evidence that would rule out
this kind of interpretations,) Until these questions are answered, the
results of the survey are worthless as evidence for the conclusion.

第七宗罪 gratuitous assumption （無中生有的假設、錯誤假設）
The author falsely depends on gratuitous assumption that.... However,
no evidence is stated in the argument to support this assumption. In
fact, this is not necessarily the case. For example, it is more likely
that.... Therefore, this argument is unwarranted without ruling out such
possibility


--
Dustin Deng
(一戰自修760，AWA 5.5)

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※ 編輯: danyuchn (61.230.103.195), 09/01/2014 15:05:38
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