Comparisons involving ellipsis

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Comparisons involving ellipsis

by aiming800 » Tue Sep 14, 2010 5:10 am
HI Stuart,

I badly need to understand the concept of ellipsis to tackle the GMAT questions
involving comparisons along with ellipsis. Most of the times I go wrong with these
questions. I would like to discuss the below two questions with this regard.

In the first question aren't we comparing "same time" with the "civilizations"

Please consider the bolded part in the question

that flourished at the same time as the civilizations in the Nile delta and the river.

Is it a logical comparison?

Shouldn't it be

that flourished at the same time as flourished the civilizations in the Nile delta and the river.

Similarly in the second question

prices are expected to be higher this year than last

Aren't we comparing the prices this year with the last year rather than prices this year with

the prices last year.

Shouldn't it be as follows

Heating-oil prices are expected to be higher this year than that of last year OR



Heating-oil prices are expected to be higher this year than they were last year


The above two construction makes sense to me but not the original one.

1.Salt deposits and moisture threaten to destroy the Mohenjo-Daro excavation in Pakistan, the site of an ancient civilization that flourished at the same time as the civilizations in the Nile delta and the river valleys of Tigris and Euphrates.

a. same
b. that had flourished at the same time as had the civilizations
c. that flourished at the same time those had
d. flourishing at the same time as those did
e. flourishing at the same time as those were



2.Heating-oil prices are expected to be higher this year than last because refiners are paying about $5 a barrel more for crude oil than they were last year.

(A) Heating-oil prices are expected to be higher this year than last because refiners are paying about $5 a barrel more for crude oil than they were
(8) Heating-oil prices are expected to rise higher this year over last because refiners pay about $5 a barrel for crude oil more than they did
(C) Expectations are for heating-oil prices to be higher this year than last year's because refiners are paying about $5 a barrel for crude oil more than they did
(d) It is the expectation that heating-oil prices will be higher for this year over last because refiners are paying about $5 a barrel more for crude oil now than what they were
(E) It is expected that heating-oil prices will rise higher this year than last year's because refiners pay about $5 a barrel for crude oil more than they did.




I know in these kind of questions some part of sentence from the former part of the comparison is implied or understood in the later part of the comparison, but how can I know that which is that part? Is it the noun, verb, or anything else from the previous part which is implied to the later part?

If I am not wrong there is a technical term "ellipsis" for these kind of comparisons but I don't know much about it. I really need to know that what are the possible kind of ellipsis that can be tested by GMAT and how to tackle those.


Stuart, I will be really grateful to you if you can explain this in detail to me.

Thanks,
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by lunarpower » Wed Sep 22, 2010 2:54 am
@aiming800, if you have a comparison using "more than", you can logically complete that with anything that is parallel to something in the first part (and makes logical sense).
e.g.
SUBJ2 VERB2
or
SUBJ2
or
PREP PHRASE 2 (if there's a PREP PHRASE 1 in the original)
etc.

e.g., all of the following are correct:
i can lift more weight at the gym than my brother.
i can lift more weight at the gym than my brother can.
i can lift more weight at the gym than in my basement.

if you're interested in finding the exact parallel constructions, the ones in #1 are "i" and "my brother"; the ones in #2 are "i can" and "my brother can"; the ones in #3 are "at the gym" and "in my basement".

so, "flourished at the same time as the civilizations..." is constructed just like the first one of these, and so is correct.

--

TWO INSTANCES IN WHICH YOU CAN'T JUST USE A NOUN:

1) VERB TENSE SHIFT
if there is a change in verb tense between the two halves of the comparison, then you MUST include the verb in both halves. (if the verb is omitted in the second part of the comparison, then the implication is that the tense is the same in both halves.)

so:
Heating-oil prices are expected to be higher this year than they were last year
--> correct
BUT
if you wrote
Heating-oil prices are expected to be higher this year than last year
then this would be incorrect, since there must be a tense shift between what is happening this year and what happened last year.

2) AMBIGUITY

i know more about shakespeare than my brother
ambiguous. 2 meanings.
two ways we can resolve this problem by adding another word:
1) i know more about shakespeare than does my brother --> i'm a bigger shakespeare nerd than my brother is.
2) i know more about shakespeare than about my brother --> my brother and i were separated at birth, so i know more about shakespeare than i do about him.

for an official problem that's like this, see #103 in the blue 2nd edition OG verbal supplement (= #106 in the purple 1st edition). the problem about inuits of the bering sea.
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by shashank.ism » Wed Sep 22, 2010 3:11 am
Nice explanation lunarpower esp. the ambiguity one.....
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by aiming800 » Wed Sep 22, 2010 3:34 am
Thanks a lot Ron for your prompt response.

But I have a serious doubt here.

As you quoted

(if you wrote
Heating-oil prices are expected to be higher this year than last year
then this would be incorrect, since there must be a tense shift between what is happening this year and what happened last year.)

I also believe that if there is a tense shift then we should explicitly mention the verb in the second part of the comparison

But if that is the case then why is the answer to the below question is option A?

Heating-oil prices are expected to be higher this year than last because refiners are paying about $5 a barrel more for crude oil than they were last year.


Thanks,

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by lunarpower » Wed Sep 22, 2010 4:42 am
aiming800 wrote:Thanks a lot Ron for your prompt response.

But I have a serious doubt here.

As you quoted

(if you wrote
Heating-oil prices are expected to be higher this year than last year
then this would be incorrect, since there must be a tense shift between what is happening this year and what happened last year.)

I also believe that if there is a tense shift then we should explicitly mention the verb in the second part of the comparison

But if that is the case then why is the answer to the below question is option A?

Heating-oil prices are expected to be higher this year than last because refiners are paying about $5 a barrel more for crude oil than they were last year.


Thanks,
ok yeah, that's problematic. however, fortunately, this is a non-issue in this particular problem (which is #93 from OG12), since none of the five choices actually acknowledges the change in tense. i believe this is just an oversight on the part of the problem writers.
in other words, if you have a CHOICE between writing this sentence with the tense shift and writing it without the tense shift, you should always pick the choice that actually contains the shift.

if there is a correct answer that should contain the tense shift, but lacks it (like this one), then i'm quite sure that all five choices will do the same thing. i.e., the writers just forgot.
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by GMATMadeEasy » Wed Sep 22, 2010 4:55 am
@aiming800 : I am wth you about problems involving comparison couled with ellipsis . This issue completely rocked me for long until I analysed the solutions of Ron at Manhattan site. I picked up OG (10,11 and 12) problems and GMATprep questions , and analysed in depth solutions provided by Ron . Following this , I have prepared notes with some example questions . If it interest you, I can paste my conclusions on this post or mail you.

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by GMATMadeEasy » Wed Sep 22, 2010 5:08 am
A question afte re-reading the post :)

Heating-oil prices are expected to be higher this year than last year (Incorrect)
Heating-oil prices are expected to be higher this year than they were last year (correct)

Heating-oil prices are expected to be higher this year than were last year ? Is it correct ?

As we can "fill-in" subject in right hand part without any modification, this should be correct ?

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by lunarpower » Wed Sep 22, 2010 5:12 am
GMATMadeEasy wrote:A question afte re-reading the post :)

Heating-oil prices are expected to be higher this year than last year (Incorrect)
Heating-oil prices are expected to be higher this year than they were last year (correct)

Heating-oil prices are expected to be higher this year than were last year ? Is it correct ?

As we can "fill-in" subject in right hand part without any modification, this should be correct ?
nope.
if you say "...than were X", then X becomes the subject of "were".

see above:
i know more about shakespeare than does my brother
--> "my brother" is the subject of "does".

also, see the correct answer to the inuit problem (#106 in first edition verbal supp, #103 in 2nd edition verbal supp)
--> this contains "...than were Aleuts or Inuits", in which "Aleuts or Inuits" is the subject of "were".

--

if you apply the same pattern to this new version "...than were last year", you have
subj = last year
verb = were
that doesn't work, either logically or grammatically.
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by gmat_perfect » Wed Sep 22, 2010 8:26 pm
GMATMadeEasy wrote:@aiming800 : I am wth you about problems involving comparison couled with ellipsis . This issue completely rocked me for long until I analysed the solutions of Ron at Manhattan site. I picked up OG (10,11 and 12) problems and GMATprep questions , and analysed in depth solutions provided by Ron . Following this , I have prepared notes with some example questions . If it interest you, I can paste my conclusions on this post or mail you.
Is your note on comparison? have you gathered all the comparison problems in a sheet? if you did so, please share the note with the community. it will help the community.

Thanks.

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by magnus opus » Thu Oct 28, 2010 10:47 am
I am having problems identifying the correct pattern of comparatives. To top it all the ellipsis is making it more difficult. In some cases the comparison is considered illogical and demands that we state the proper verbs and pronouns to demarcate the comparison between the quantities and in some cases, the verb is omitted for concision.

Please help
-identify the patterns there are , if any, to comparatives
-case where ellipsis is valid.

Consider the following example for ellipsis

The Dancing Doll Line sold slightly more than $3.5 million worth of toys last year, forty percent more than the Teeny Toys and nearly three times more than the Basic Blocks line.

This sentence is missing a verb (did/sold) which is claimed to be understood.
However, I believe the lack of the verb creates the possibility of an illogical comparison ( where Dancing line sold more toys than the teeny toys and basic toys.
Please point out why this is not so,Is it because The scond part forms a modifier and the toys companies have the definate article "the" before them.


Another one. Q93. O.G12
Heating oil prices are expected to be higher this year than last.

What is the ellipsis here - just the word (year) or than..(they were)..last (year).

In the above sentence we do not complain about any clarity issues.

Look at this sentence
Balding is more common among X than among Y.

here if we omit the second preposition, then the sentence is said to have an illogical comparison
Balding is more common among X than Y.
-Here the justification is that we comparing the incidence of both balding and y in X which was not intended.

SO my question is WHY DOESN'T THE SAME PROBLEM ARISE IN ELLIPSIS?

Is there pattern to the comparatives which decides whether we need to mention the verb etc.

Eg.
type 1.
They generally employ more employees than DO other businesses.

Noun verb noun -comparative- verb noun.

In the above case if we do not mention the comparison we may have portend the wrong meaning that "they" employ more workers than they employ other businesses.

DOES the ambiguity arise when the logic is not flouted in both meanings? ( however this is not so in the balding example)

type 2.
Balding is more common among X than among Y
noun verb -comparative- prep noun1 and prep noun2

Some employees are more concerned about X than about Y.

type 3.
The productivity of x is higher than that of y.
noun(attribute etc.) prep of noun1 than Pronoun attribute of y.

Protein in rice is higher than that in wheat.

In 1982, the median income for married couples families with a wage earning wife was $ 900 more than that of families in which on the husband was employeed.

The above sentence again forms the pattern3.

Last year, Land values in most part of pinelands rose almost as fast as, and in some parts even faster than, those outside pineland.

Land values (att) in (prep) pinelands (noun) -comparative- those(pronoun) outside(prep) pineland(noun)



However look at the following two sentences, their comparisons are hard to tell while selecting

Telephone companies would enable customers to receive internet data over regular telephone lines at speeds much higher than are currently possible
-this does not seem parallel, though it is correct.


INCORRECT-
In Holland, a larger percentage of the gross national product is spent on defense of their coasts from rising
seas than is spent on military defense in the United States.
OE states-A states confusedly that Holland spends a percentage of its
gross national product on military defense in the United States
Correct-
Holland spends a larger percentage of its gross national product on defending its coasts from rising
seas than the United States does on military defense.

Summarizing the above in simple terms my doubt it -

How do we tell when there is a illogical meaning being portrayed, and when do we tell than ellipsis is correct or required?


One last thing
Og 12 Pg 718 Q66. The official Explanation says : "as big as" is idiomatically incorrect, however it frequently uses the construction "as many as". Please explain this contradiction.

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by lunarpower » Fri Oct 29, 2010 1:36 am
first, on the topic of comparisons, a little shameless self-promotion:
if you watch the recording for october 21 at the following link...
https://www.manhattangmat.com/thursdays-with-ron.cfm
... the last 45 min. or so consists of a discussion on comparisons.
magnus opus wrote:Consider the following example for ellipsis

The Dancing Doll Line sold slightly more than $3.5 million worth of toys last year, forty percent more than the Teeny Toys and nearly three times more than the Basic Blocks line.

This sentence is missing a verb (did/sold) which is claimed to be understood.
However, I believe the lack of the verb creates the possibility of an illogical comparison ( where Dancing line sold more toys than the teeny toys and basic toys.
Please point out why this is not so,Is it because The scond part forms a modifier and the toys companies have the definate article "the" before them.
where'd you get this sentence? which authority is claiming that it is correct/incorrect?
this doesn't look like an official problem, so the identity of the source is important in judging the credibility of this statement.




One last thing
Og 12 Pg 718 Q66. The official Explanation says : "as big as" is idiomatically incorrect, however it frequently uses the construction "as many as". Please explain this contradiction.
there are two different ways to explain why "as big as 30 feet long" is incorrect; you should take note of both of them (both are valid):
1) REDUNDANCY: you don't want to include both "big" and "long".
2) NOT LITERALLY TRUE: if you interpret this literally, you're saying that "30 feet long" is something that has a certain size; that's not true.
another example:
josh is taller than joe --> makes sense
josh's height is greater than joe's height --> makes sense
josh's height is taller than joe's height --> doesn't make sense; incorrect (a height can't be taller than another height).
see here:
https://www.manhattangmat.com/forums/pos ... tml#p44328
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by lunarpower » Fri Oct 29, 2010 1:38 am
Another one. Q93. O.G12
Heating oil prices are expected to be higher this year than last.

What is the ellipsis here - just the word (year) or than..(they were)..last (year).
the omitted word here is just "year".
there's no problem with tense shifting here, since infinitives don't have a tense (i.e., "to be" is neither anchored in the present nor anchored in the past).

if this problem were written "heating oil prices are higher this year than last year", then i believe there would be a problem -- since "are" is a present-tense verb, that sentence would have to actually include the verb "were" (past tense) to avoid a tense issue.
Eg.
type 1.
They generally employ more employees than DO other businesses.

Noun verb noun -comparative- verb noun.

In the above case if we do not mention the comparison we may have portend the wrong meaning that "they" employ more workers than they employ other businesses.
i'm pretty sure that this one would be fine both ways -- i.e., i don't really think that the version without "do" would be considered ambiguous.
in order to have genuine ambiguity, both versions of the sentence must contain proper parallelism of both grammar and meaning.

for instance, here is a genuinely ambiguous sentence:
josh has known tim longer about stephanie.
this can mean two things:
(1) josh has known tim longer than josh has known stephanie;
(2) josh has known tim longer than stephanie has known tim.
the reason why both of these meanings are legitimate sentences is that they are both perfectly parallel: (1) is parallel because the parallel elements are tim and stephanie (both people, both in the same context), and (2) is also parallel because the parallel elements are josh and stephanie (both people, both in the same context).

i don't think that your example above would be considered ambiguous, because the second interpretation doesn't pass the test of parallelism: "employees" and "businesses" aren't parallel concepts.
However look at the following two sentences, their comparisons are hard to tell while selecting

Telephone companies would enable customers to receive internet data over regular telephone lines at speeds much higher than are currently possible
-this does not seem parallel, though it is correct.
is this sentence from an official source or from a third-party source?

if this sentence is from a third-party source, it's important to corroborate its conclusions with some sort of evidence from the official materials.
INCORRECT-
In Holland, a larger percentage of the gross national product is spent on defense of their coasts from rising
seas than is spent on military defense in the United States.
OE states-A states confusedly that Holland spends a percentage of its
gross national product on military defense in the United States
take a look at what is parallel, and then use meaning to determine whether those are the things that should be parallel. in the sentence quoted above, i've put the parallel elements in red, so that you can look at them easily.
this is a mistake. it's not grammatically incorrect, but the meaning is nonsensical -- the meaning implies that both of the red things are elements of the gross national product of holland.
How do we tell when there is a illogical meaning being portrayed
take a look at the elements that are grammatically parallel, and tell whether they are the elements that are logically intended to be parallel. (the latter isn't going to be determined by any sort of rule; you're just going to have to use your intuition / common sense.)

here are four sentences; see if you can tell why the correct ones are correct and why the incorrect ones are incorrect:

For the New Year, John promised to get in shape by running on the treadmill and lifting weights. --> correct

For the New Year, John promised to get in shape by running on the treadmill and to lift weights. --> incorrect

For the New Year, John promised to get in shape by running on the treadmill and saving money. --> incorrect

For the New Year, John promised to get in shape by running on the treadmill and to save money. --> correct

these four sentences constitute a fairly good test of whether you are sufficiently judging sentences on their meaning, rather than just on their grammar. the first and third sentences are written with exactly the same grammar, but the first is correct and the third is incorrect; similarly, the second and fourth sentences are written with exactly the same grammar, but the second is incorrect and the fourth is correct.
make sure that you understand why.
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by magnus opus » Sat Oct 30, 2010 3:34 am
lunarpower wrote:first, on the topic of comparisons, a little shameless self-promotion:
if you watch the recording for october 21 at the following link...
https://www.manhattangmat.com/thursdays-with-ron.cfm
... the last 45 min. or so consists of a discussion on comparisons.
magnus opus wrote:Consider the following example for ellipsis

The Dancing Doll Line sold slightly more than $3.5 million worth of toys last year, forty percent more than the Teeny Toys and nearly three times more than the Basic Blocks line.

This sentence is missing a verb (did/sold) which is claimed to be understood.
However, I believe the lack of the verb creates the possibility of an illogical comparison ( where Dancing line sold more toys than the teeny toys and basic toys.
Please point out why this is not so,Is it because The scond part forms a modifier and the toys companies have the definate article "the" before them.
where'd you get this sentence? which authority is claiming that it is correct/incorrect?
this doesn't look like an official problem, so the identity of the source is important in judging the credibility of this statement.


This is from Kaplan 800 s.c. Even though this is a reputed prep company, i beginning to doubt its credibility for reasons i put up here.
https://www.beatthegmat.com/kaplan-800-sc-t68764.html
Do you think this sentence is ambiguous?

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by magnus opus » Sat Oct 30, 2010 4:05 am
lunarpower wrote:
Another one. Q93. O.G12
Heating oil prices are expected to be higher this year than last.

What is the ellipsis here - just the word (year) or than..(they were)..last (year).
the omitted word here is just "year".
there's no problem with tense shifting here, since infinitives don't have a tense (i.e., "to be" is neither anchored in the present nor anchored in the past).

if this problem were written "heating oil prices are higher this year than last year", then i believe there would be a problem -- since "are" is a present-tense verb, that sentence would have to actually include the verb "were" (past tense) to avoid a tense issue.
So in this case are you basically implying that, since "year" has been implied elliptically, we are to assume any other elliptical connotation( of the verb) cannot hold in the case at hand?
But then, the question arises: How do we judge which one has been implied? In this case it easy to pick "year" because thhe word "last" creates that expectation. Are there any other such examples where one has to make a pick.

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by magnus opus » Sat Oct 30, 2010 4:30 am
saw the video Ron, all the concepts are crystal clear....thank you very much.