Inference vs Assumption

Hi

Thnaks Chiranjeev . This is now clear after going through EGMAt CR CONCEPTS.
Initially I have drawn difference between inference and assumption only on the basis of restatement and new information.

But this blog has shoen me therse two's are completely diffeent..I dont need to assume anything to draw inference.

Regards,
Sreshtha

Hi Chiranjeev,

I have a doubt.

A proposed change to federal income tax laws would eliminate deductions from taxable income for donations a taxpayer has made to charitable and educational institutions. If this change were adopted, wealthy individuals would no longer be permitted such deductions. Therefore, many charitable and institutions would have to reduce services, and some would have to close their doors.
The argument above assumes which of the following?
(A) Without incentives offered by federal income tax laws, at least some wealthy individuals would not donate as much money to charitable and educational institutions as they otherwise would have.
(B) Money contributed by individuals who make their donations because of provisions in the federal tax laws provides the only source of funding for many charitable and educational institutions.
(C) The primary reason for not adopting the proposed change in the federal income tax laws cited above is to protect wealthy individuals from having to pay higher taxes.
(D) Wealthy individuals who donate money to charitable and educational institutions are the only individuals who donate money to such institutions.
(E) Income tax laws should be changed to make donations to charitable and educational institutions the only permissible deductions from taxable income.



My question is whether choice D
"Wealthy individuals who donate money to charitable and educational institutions are the only individuals who donate money to such institutions."
can be called a stengthener

According to the definition of strengthener any new statement that makes the conclusion more believable is a strengthener.
Now, this choice does make the conclusion more believable, but with an assumption that these wealthy individuals will contribute less if they don't get the tax incentive. Without this assumption, can choice D make the conclusion more believable by itself?

So my doubt is that if a statement makes a conclusion more believable, but with the help of another statement which is not explicitly stated in the passage, can it be called a Strengthener?
Same for weakener ie if a statement makes a conclusion less believable ,but with the help of another statement which is not explicitly stated in the passage, can it be called a Weakener?


Thanks,
Sarmistha

Hi Sarmistha,

Yes, option D can be called a strengthener because as you correctly said, it makes the conclusion more believable.


Without this assumption, option D will not be able to strengthen the conclusion because if the wealthy individuals are going to donate the same amount of money even when there are no tax incentives, then the conclusion just cannot hold, no matter how many strengtheners you provide.


The answer to both the above questions is YES. When we say that a strengthener increases the belief in the conclusion and not necessarily prove the conclusion, we mean that the conclusion can still not hold true even in the presence of a strengthener. Right? Because it only increases belief and does not necessarily prove the conclusion correct.

So, if the conclusion does not hold in a situation (which will be the case when the assumption does not hold), then obviously it's futile to even say that the strengthener has increased the belief in the conclusion. It cannot do so simply because the conclusion does not hold.

So, all in all, you generally require assumptions for strengthener to strengthen the conclusion. Similar observation holds for weakeners also.

Now, here is the main thing: you cannot assume anything and everything even counter-intuitive things which go against the common sense. You have to make logical common sense assumptions when evaluating option statements for strengtheners or weakener.

For example, in the question above, the passage is essentially saying that one benefit of donation (i.e. tax deductions) is no longer there. Now, when one benefit is removed for any product or service, it is only logical to assume that people who valued that benefit will reduce their consumption of the product or service. In this case, similarly, it is only logical to think that some wealthy who valued the benefit of tax deduction will reduce their donations. So, we are making a very logical assumption, not a far fetched one.

I think this is an important thing to understand: you can make assumptions but they should not be counter-intuitive or far fetched. For example: you cannot assume in this question that by removing one benefit of tax-deduction, no wealthy individual will donate at all. This is a far-fetched one.

So, just be careful while making assumption when evaluating option statement for weakeners and strengtheners.

Hope this helps

Thanks,
Chiranjeev

Hello,

Can anyone help me on this!!!

Generally scientists enter their field with the goal of doing important new research and accept as their colleagues those with similar motivation. Therefore, when any scientist wins renown as an expounder of science to general audiences, most other scientists conclude that this popularizer should no longer be regarded as a true colleague.

The explanation offered above for the low esteem in which scientific popularizers are held by research scientists assumes that

(A) serious scientific research is not a solitary activity, but relies on active cooperation among a group of colleagues
(B) research scientists tend not to regard as colleagues those scientists whose renown they envy
(C) a scientist can become a famous popularizer without having completed any important research
(D) research scientists believe that those who are well known as popularizers of science are not motivated to do important new research
(E) no important new research can be accessible to or accurately assessed by those who are not themselves scientists

Confused between Choice C and Choice D.

Conclusion : Popularizer can not be regarded as true scientist or Popularizer do not have a goal of doing important research

(C) a scientist can become a famous popularizer without having completed any important research
Negating C : a scientist can NOT become a famous popularizer without having completed any important research
The negation of Choice C is attacking the conclusion.

(D) research scientists believe that those who are well known as popularizers of science are not motivated to do important new research
Negating D : research scientists believe that those who are well known as popularizers of science ARE motivated to do important new research
Again this negation is also attacking the conclusion.


How to decide between C and D ?

Hi Karan,

The answer to your question is simple: Option C is about past and option D is about future. The scientists are only concerned whether their colleague would be motivated to do research in the future and not concerned whether their colleague actually did important research in the past.

Option C seems to indicate that the guy who became famous popularizer actually must have done important research. But we are not concerned what he has done so far; we are concerned about his motivation for the future.

Let me know if you still have doubts.

Thanks,
Chiranjeev

Hello Chiranjeev

Yes got the point.

Thanks alot!!!

Hi Chiranjeev,

with reference to Question

A proposed change to federal income tax laws would eliminate deductions from taxable income for donations a taxpayer has made to charitable and educational institutions. If this change were adopted, wealthy individuals would no longer be permitted such deductions. Therefore, many charitable and institutions would have to reduce services, and some would have to close their doors.
The argument above assumes which of the following?
(A) Without incentives offered by federal income tax laws, at least some wealthy individuals would not donate as much money to charitable and educational institutions as they otherwise would have.
(B) Money contributed by individuals who make their donations because of provisions in the federal tax laws provides the only source of funding for many charitable and educational institutions.
(C) The primary reason for not adopting the proposed change in the federal income tax laws cited above is to protect wealthy individuals from having to pay higher taxes.
(D) Wealthy individuals who donate money to charitable and educational institutions are the only individuals who donate money to such institutions.
(E) Income tax laws should be changed to make donations to charitable and educational institutions the only permissible deductions from taxable income.


Can you please explain the negation of choice B and D. I am able to apply negation to option A and in that case conclusion shatters, but I am confused while applying negation to option B and D

Thanks,
Ankit

Hi Ankit,

Please do go through Chiranjeev's analysis of the negation of choice D here : https://gmatclub.com/forum/inference-vs-assumption-146758.html#p1265147

I am certain that after going through the above analysis, you'll be able to correctly apply the negation test to choice B as well. However, should you face any problems with the same, please do feel free to post your query here. Please make sure that when you do so, you also share your analysis of choice B and application of the test to it. That way, we'll be able to take our discussion forward more productively.

Regards,

Neeti.

Hi Chiranjeev

I am new to GMAT Forum going through the Q and A of Assumptions and inference. Could you please tell me in certain places what does OFS stands for. As in many answers ehich are not the correct answers i find this written as OFS. Please do let me know. Thanks

Hi Sunil,

Welcome to the forum

OFS stands for Out Of Scope. It essentially means that the option statement is talking about something which is completely irrelevant to the given passage/stimulus.

Do you have any specific doubt in an option statement? Please let me know

Thanks,
Chiranjeev

Hi I wanted to know some answers reasons and have some techniques in getting the correct answers regarding negation. Please do let me know.

Ex1: Most GMAT test takers who take the exam after 1 month of preparation perform better than they did in their first mock. (Multiple answers may be correct)

a) Most GMAT test takers who take the exam after 1 month of preparation do not perform better than they did in their first mock.
b) All GMAT test takers who take the exam after 1 month of preparation perform better than they did in their first mock.
c) No GMAT test taker who takes the exam after 1 month of preparation performs better than they did in their first mock.
d) At least half of GMAT test takers who take the exam after 1 month of preparation perform better than they did in their first mock.
e) Up to half of GMAT test takers who take the exam after 1 month of preparation perform better than they did in their first mock.
f) Up to half of GMAT test takers who take the exam after 1 month of preparation do not perform better than they did in their first mock.
g) Half or more of GMAT test takers who take the exam after 1 month of preparation do not perform better than they did in their first mock.

I feel firstly seeing the question I will negative Most and I can ssee Upto Half is the correct options so I have E and F are the only options right ?

So let me follow the rules I will see Upto Half is the negation version of Most I will see where verb ruloe negation is not applied ?

So considering E option I find this is not verb negated and F is verb negated. So clearly E is the answer.

Lets see the next options now I will see where Most is there in the options . So it means I will Apply Verb Rule Negation and there is no change in the subject So I have G as the option and let me see whether verb is negated in this case yes it is undoubtedly ("do not perfeorm better"). So G is my second option.

Now lets go to the third option that Most is same so let me apply verb rule in First option that is so I find ("Do not perform better") so this is my third option.

Answers : A,E,G

My Logic is also same like yours see whether subject is changed then no verb change should be there and whereever ver change is there no subject change should happen. Please do let me know why in your answer sets i do not find option A as the correct answer.

Ex2: Every internet dating profile in the world begs for some spontaneity (Multiple answers may be correct)

a) Not every internet dating profile in the world begs for some spontaneity
b) No internet dating profile in the world begs for some spontaneity
c) Most internet dating profiles in the world begs for some spontaneity
d) Some internet dating profiles in the world do not beg for some spontaneity

Applying same logic as in Ex 1 first let me negate subject so I have A as the option and there is no verb change here so A is the correct answer .

Applying Verb Negation Rule Some is the super set of Every and there is a verb change in option D("Do Not beg spontaneity") option D is correct one.

Answers A and D

Ex3: Innovations such as iPhone happen nowhere outside Apple. (Multiple answers may be correct)

a) Innovations such as iPhone do happen outside Apple.
b) Innovations such as iPhone do not happen outside Apple.
c) No other company is as innovative as Apple is.
d) Innovations such as iPhone happen both inside Apple and in other companies.

Applying verb negation Rule it happens outside these so A and D are correct

Ans: A,D


Ex4: No sane person who has never given a ride to a stranded passenger will give a ride to someone dressed in a hood (Multiple answers may be correct)

a) Some sane people who have never given a ride to a stranded passenger will give a ride to someone dressed in a hood
b) Atleast one sane person who has never given a ride to a stranded passenger will give a ride to someone dressed in a hood
c) All sane people who have never given a ride to a stranded passenger will give a ride to someone dressed in a hood
d) No sane person who has ever given a ride to a stranded passenger will give a ride to someone dressed in a hood.
e) Some sane people who have given a ride to a stranded passenger will give a ride to someone dressed in a hood

Applyling Subject Negation I do find No negation is All and Some and its present in option C and A and there is also no verb change.

Applying verb change I find D has no subject change but there is verb change as well ("Never Given a Ride")

Answers: A,C,D

Please do let me know is this the correct approach as I am finding the article quiet confusing

And I have attended some Free verbal Questions and Am really struggling to find the answer I find out of 20 question I have given only 15% correct. what could I do to improve it. Please do let me know.

Thanks in advance waiting for a reply.

Hi Chiranjeev Sir

Could you please let me know the above answer I am waiting for the reply. And to correct me in concepts if I am wrong

Hi chiranjeev

Could yu please do let know the answer As I have tried to post some comments and reasons and some clarifications are required from your side. So Please let me know the answers and my weakness and all in the above question and logic behind it

Hi Sunil,

Apologies for the delay in responding.

However, I have a small request to make before I respond to your analysis. Since these questions pertain to our article on negation, would you please post this analysis on that thread so that all the relevant things stay together. Here's the link to the article for easy reference.

article-what-and-how-to-negate-6-exercise-questions-138510.html

I'll look forward to your post on that article thread and will try to respond as early as possible.

Thanks,
Chiranjeev

Hi Chiranjeev Sir

Apologies for posting the queries in wrong thread and requestingfor the result. I have posted in the correct thread please do reply me over there when you have time.

Thanks

Regards
Sunil
93831831666

Amazing article from amazing people.

All though, the above deductions are accurate, I have a query pertaining to Option A.
Conclusion is: When a scientist becomes popular among a general audience for explaining principles of scienceother scientists have less esteem for this popularizer, no longer regarding such a scientist as a serious colleague.

It does not explicitly mention that lack of motivation to do important new research is the cause for being rejected.

Alternate View Passage also mentions " and accept as their colleagues those with similar motivation " so as per option A, since the scientist is the only one being acknowledged, it might cause his colleagues to feel let down and so the rejection, as its supposed to be a Collective effort and not INDIVIDUAL.

What is the flaw in the above reasoning, if any?