need some tips on assumption, flaw and must be true type?

superman3105
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Joined: Thu Jun 07, 2012 2:49 am

need some tips on assumption, flaw and must be true type?

Postby superman3105 » Thu Jun 07, 2012 3:17 am

Hey everyone,
I am struggling with the assumption, must be true and flaw questions. I only get 50-60 percent correct answer . These questions are very time-consuming too. I'm currently using the biblescore only, i tried the mahattan and kaplan but they werent really helpful at all. Can anyone help me with these types?

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Br3v
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Re: need some tips on assumption, flaw and must be true type?

Postby Br3v » Thu Jun 07, 2012 3:17 am

superman3105 wrote:Hey everyone,
I am struggling with the assumption, must be true and flaw questions. I only get 50-60 percent correct answer . These questions are very time-consuming too. I'm currently using the biblescore only, i tried the mahattan and kaplan but they werent really helpful at all. Can anyone help me with these types?


Just drill those individual types

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PDaddy
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Re: need some tips on assumption, flaw and must be true type?

Postby PDaddy » Thu Jun 07, 2012 5:06 am

superman3105 wrote:Hey everyone,
I am struggling with the assumption, must be true and flaw questions. I only get 50-60 percent correct answer . These questions are very time-consuming too. I'm currently using the biblescore only, i tried the mahattan and kaplan but they werent really helpful at all. Can anyone help me with these types?


Flaw and MBT reasoning types are really one in the same in terms of the approach you can use in solving them. This actually holds for six types: (1) Must Be True/Inference, (2) Main Point, (3) Point at Issue, (4) Flawed Reasoning, (5) Method of Reasoning, and (6) Parallel Reasoning. Understand that, in all six cases, the right answers absolutely cannot be false/must be true given the information. Secondly, the wrong answers are not kind of wrong, they're REALLY wrong...terribly wrong. You have to accept that in order to get good at doing these types of problems.

That means, the stimulus leads to certain conclusions that cannot be false (and which therefore must be true) given its information. The six types are all the same in that their answers cannot be false given the stimulus information. If you see an answer that can be true but doesn't have to be true, it's wrong. Furthermore, no new information can be included in the correct answers. New information answers are "out-of-scope" and are therefore wrong.

Forget prephrasing the answers to these six question types because there are too many possible correct answers to prephrase. Knowing this gives you power, because you can move right to the answer types. So what do you do then?

For MBT/Inference questions, read the question stem carefully, then read the stimulus carefully. Must Be True/Inference stimuli do not have conclusions because (like paradox stimuli) they are not "arguments". Your task is to identify a suitable - though not necessarily ideal - conclusion in the answers (something the stimulus proves).

Scan the answer choices for out-of-scope answers or answers that otherwise look obviously wrong. There will usually be three of them, occasionally just two. You will almost always narrow down to (1) a "trap" answer that looks facially correct and (2) the real McCoy.

Next, use "negation technique" on each remaining answer.

Ex: "The driver will pay a toll" is negated to state that "The driver will NOT pay a toll".

Ex #2: "All monkeys are tempermental" is negated to state that "NOT all monkeys are tempermental".

Note: Notice how all = 100% and NOT all = 0-99%. This is logical negation. Opposites are different, and that isn't what you want.

Place the negated answer after the premises. Remember, if it cannot be true in its negated form it is the correct answer, because you have shown that it must be true. If the negated form of an answer is consistent with the stimulus, it is wrong.

There are about 20 different types of flaws used on LSAT questions. I can only tell you that you should first decide whether the flaw is one of "omission" or "commission". The argument either assumes something or neglects to consider something. Consider the vices used to arrive at the conclusions. If, for example, statistics are used to advance an argument, how is the argument likely to be flawed? For one, an argument can assume whole for parts, or vice versa.

Ex: "All buildings on this campus are clean, therefore the university is clean". That's a flawed argument that assumes the condition of the whole because of the condition of some of its parts. Doesn't a college campus have cafeterias and sports facilities? What if those are shit-holes?

Ex #2: "This automobile is expensive, therefore all of its parts are expensive." Really? Is that necessarily true?

Ex #3: Harvard law grads are incompetent. I know one who is totally incompetent and never wins a case." That's called an "unrepresentative sample flaw"

Ex #4: "Steve claims this bank is headed for a collapse, but he is clearly lying. Although he is an expert in economics, he was once convicted of imbezzlement, so he cannot be trusted."

That's a "source flaw". It shoots the messenger instead of the message, which may be legit, despite the cited evidence to the contrary. Steve could be telling the truth despite his past trangressions, correct?

There are many more flaw types, but I cannot discuss them all here.

For assumption questions, you want to read closely for the premises and conclusions. Look for an elements that is prominent in the premises but not the conclusion, or vice versa and which may bridge the two together. For example, the premises may speak about "teachers, but the conclusion may offer a scope shift that either narrows or broadens that element to include "college professors" or "scholars". The correct assumption will bridge the two together and address the scope shift.

If there is no scope shift, the elemental approach should still be the same. look for elements that repeat in the premises but are apparently altered in some way in the conclusion, or vice-versa. The correct answer will address the change. use the negation technique to check your answer. If the negated answer kills the argument, the answer is correct.

Assumption answer choices are usually easy to narrow down. First, answers with new information can be correct, but wrong answers introduce vague words that often stick out, like "some", "most", etc. They also tend to introduce irrelevant info. For example, if a stimulus mentions teachers and college professors, a wrong answer might mention janitors.

Answers that mention what people feel or believe are often wrong. You have to do these repeatedly to get good at them, but they are not that difficult.

In genral, you must become adept at identifying wrong answers quickly, or you will not have the kind of success you want. It takes a lot of time and effort.

I know this isn't completely helpful, but I thought I would weigh in just to give you some tips on approaches. I would recommend that you invest in the PowerScore LR Bibl and read it cover-to-cover twice. Do every exercize. You will improve immediately.




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