Q12 - Poor nutrition is at the root

[dsorchestra90]

I eliminated A because it is out of scope. I eliminated B because it is irrelevant. I eliminated C because he is suggesting a correlation not a cause. I eliminated D because I think it is a mistaken reversal, because a high nutrient diet doesn't necessitate non violence, rather a poor diet correlates with violence. I chose E because it proves that the study is working because only the individuals who changed their diets have seen any improvement. Is this correct? I had a hard time between D and E, but in the end I was convinced that E is correct. Can someone go over why D is wrong?

[bbirdwell]

We can be more confident in eliminating (D) by focusing on the conclusion.

I agree with your instinct to be skeptical about (D) because it includes the opposite sides of the nutrient/violence construction, but it's not exactly a mistaken reversal. Since the conclusion is about poor-nutrition/violence, a choice about good-nutrition/non-violence is likely to be less relevant, though not necessarily wrong. We need to take a closer look.

I think the main issue with (D) is the word "many." If only "many" of the high-nutrient inmates were non-violent, that must mean that "some" of them were violent. This actually opposes our conclusion.

Make sense?

[mit311]

Why is C) not right? Doesn't it prove poor nutrition ->Violent Behavior

[bbirdwell]

Nope. It just says "Many offenders," and it says "consumed a low-nutrient food." This is much different from the argument, which links violent behavior with a low nutrient diet.

[funner567]

Nope. It just says "Many offenders," and it says "consumed a low-nutrient food." This is much different from the argument, which links violent behavior with a low nutrient diet.

I'm confused, specifically in the stimulus it says "researches observed that in a certain institution for young offenders, the violent inmates among them consistently chose, from the food available, those items that were low in nutrients."

Why is the fact that food is used in "C" incorrect?

Which leads me to another question... is E correct partially because it re-uses the "violent inmates in the institution" as part of its evidence, while all the others state just "young offenders"

thanks.

[chike_eze]

...
I'm confused, specifically in the stimulus it says "researches observed that in a certain institution for young offenders, the violent inmates among them consistently chose, from the food available, those items that were low in nutrients."

Why is the fact that food is used in "C" incorrect?

Which leads me to another question... is E correct partially because it re-uses the "violent inmates in the institution" as part of its evidence, while all the others state just "young offenders"

thanks.

I share some of the questions raised here. I am confused about the correct answer to this question.

My argument core was:
causative link between poor nutrition and violent behavior, i.e., poor nutrition leads to violent behavior.

If my argument core is accurate, then I do not understand why E is correct. It seems to link high nutrient diet and behavior.

Please add your argument core and fully explain why each option is wrong or right (especially C, D, and E)

[bbirdwell]

Conclusion:
violent behavior is related to poor nutrition .

Premises:
1. violent inmates chose low nutrient foods
2. some violent inmates given high-nutrient diet
3. there was improvement in their behavior over four months

The tough thing about this one is that it's a pretty decent argument as-is. It's often much easier to strengthen a bad argument, by supporting or validating big assumptions. Here, we should go to the choices with our focus on the conclusion and the one piece of evidence (an experiment).

(A) way off -- # of crimes?
(B) way off - easier and cheaper?
(C) maybe
(D) maybe
(E) maybe

Let's dig in a little deeper.
(D) is a common wrong answer on arguments like this. Demonstrating that the opposites of what we're discussing occur together does not logically strengthen the argument at hand. The fact that some tall people are good at basketball does not strengthen the argument that short people are bad at it.

(C) close!
(E) better. Why? Because it validates the only piece of evidence the argument has -- the experiment. (E) basically says, "There was a good control group in the experiment." This helps tremendously. For, if it weren't true, the experiment would be bunk, wouldn't it? What if every single inmate in the experiment, good or poor nutrition, became less violent over the four months? Suddenly the possibility opens that maybe something else caused the improvement, like a new recreational facility, or a new warden, or anything we can imagine.

This is much, much stronger than (C).

Again, one reason (C) is less strong is because the argument is about "diet" and "nutrition," which are about the regular consumption of some foods. Just because a vegan inmate ate a candy bar and got violent, this does not strengthen this particular argument as much as (E). Notice another subtle distinction here: we are asked to strengthen the ARGUMENT, which is the connection between the given evidence and the conclusion. This is subtly different from merely strengthening a CONCLUSION itself.

(E) focuses on strengthening the logic of the given argument, while (C) arguably relates only to the conclusion, the shaky points being the vague word "many," the distinction between "nutrition" and a single food item, and also the time lag. Would being violent several days after eating a candy bar really support the argument at hand, or even the just conclusion?

[gs.abhinav]

Conclusion:
Demonstrating that the opposites of what we're discussing occur together does not logically strengthen the argument at hand. The fact that some tall people are good at basketball does not strengthen the argument that short people are bad at it.

Well isn't the author doing the same thing? Stating the opposite.

First she states that: poor-nutrition --> violence.
Then she goes on to state that: high-nutrition --> subsides violence.

Secondly, one of the ways to strengthen a causal argument is to show that when "the cause does not occur then the effect does not occur".

(D) does exactly that? doesn't it? although the qualifier "may" is a bit tricky here.

[ManhattanPrepLSAT1]

I'm going to jump in for Brian here for now, as he's got a ton on his plate at the moment.

The issue is that the argument never claimed that good nutrition causes good behavior. It gets close but the conclusion is about poor nutrition causing violent behavior. There is a correlation established between good nutrition and good behavior but that's not quite the same. Notice how answer choice (E) provides an example of the absence of the cause with an absence of the effect. The example relates to the causal conclusion, whereas answer choice (D) is about the correlation in the evidence.

So if you were down to (D) and (E), stay close to the conclusion and go for (E)!

Does that make sense?

[cardsfan04]

I've watched the HW video and I've read through this thread. But, I'm still a little confused. I got it right when doing it on my own, but I wasn't very confident.

I get A, B, and C being wrong, so no issues there. But, I still really want to choose D. I think I know why I'm caught though.

When taking it I created a contrapositive, but maybe that was unnecessary. I know there isn't an actual if/then statement in the stimulus, but it seemed to be implied.

PN-->VB
-VB-->-PN

PN= poor nutrition
VB= violent behavior

The conclusion can be rephrased as "If an inmate has a low-nutrient diet, they are more likely to be violent," right? Or am I straying too far?

If I can state that as the conclusion, D seems to be consistent with the contrapositive. It has non-violent offenders lacking poor nutrition. Am I wrong for trying to make a contrapositive here without an actual if/then statement?

Basically, I thought that both D and E strengthened the argument, but E strengthened it more, so I went with that.

I think I might know why I'm wrong though. The author is proving what made violent offenders non-violent while the further study could have been done on already non-violent offenders (meaning their diet didn't make them non-violent, they already were non-violent). Is that the crux of the issue?

[ManhattanPrepLSAT1]

When taking it I created a contrapositive, but maybe that was unnecessary. I know there isn't an actual if/then statement in the stimulus, but it seemed to be implied.

PN-->VB
-VB-->-PN

PN= poor nutrition
VB= violent behavior

The conclusion can be rephrased as "If an inmate has a low-nutrient diet, they are more likely to be violent," right? Or am I straying too far?

There's an issue here. You're mixing up correlation and causation, which is exactly what the argument is doing.

The evidence of this argument exists in correlations between a low-nutrient diet and violent behavior. The conclusion mistakes that correlation and posits that the low-nutrition causes the violent behavior.

To strengthen the argument, make sure that whenever the presumed cause is present so is the effect, whenever the presumed cause is not present neither is the presumed effect, or eliminate a competing alternative cause.

Answer choice (E) shows that when the cause (low-nutrient diet) is present so is the effect (violent behavior) - thus strengthening the causality implied.

What all that means is that you cannot diagram the conclusion as a conditional statement, sorry! The big issue with answer choice (D) is that it's too weak. We see this often where the answer choice mentions "some" "many" "several" or "a few" and it's simply not enough to support an argument that only speaks in generalities. Answer choice (E) however doesn't have that weak language and would thus apply to every violent inmate in the institution who was not placed on a high-nutrient diet.

Make sense?

[cardsfan04]

Yeah, I think that makes sense. I think that I intuitively know that E is a better choice than D. I just struggle articulating it, which probably costs me points when my intuition is off.

As for the conditional, is it safe to assume that I can't use that unless they give me an actual "if/then" or other similar language?

[ManhattanPrepLSAT1]

it's possible to create a conditional relationship without those language cues "if, when, all, unless, only if, etc..." but it's not easy. For example A and B cannot both be accepted to the club. If A is accepted, then B is not accepted.

But for the most part in LR, they utilize the trigger words.

[huiyichen2010]

I think there IS a causal instead of a mere correlation claim. The very first sentence is "Poor nutrition is at the root ofthe violent behavior...". I suppose that means poor nutrition causes violent behavior.

The difference between D and E, I think, is that D strengthens the conclusion by offering extra evidence, while E strengthens the argument by making the original supporting evidence more credible. And the question asks for something that "strengthens the argument".

[ManhattanPrepLSAT1]

I think there IS a causal instead of a mere correlation claim. The very first sentence is "Poor nutrition is at the root ofthe violent behavior...". I suppose that means poor nutrition causes violent behavior.

I completely agree, nice work! But we both agree that the evidence does not warrant this causal connection, right? It could be that poor nutrition causes violent behavior and that good nutrition lessens the severity of violent behavior, sure. But couldn't something else explain what happened in the researchers' experiment?

Though huiyichen2010, I don't see answer choice (D) strengthening the conclusion. The findings in (D) are too weak to support the causal connection posited by the researchers. This doesn't really tell us much about those who chose a high-nutrient diet. Couldn't be that of those who did, most of them were violent? That might actually go so far as to undermine the argument. It just depends on how many is "many."

[timsportschuetz]

I think the above discussion is great! I would like to add a few things that I believe are also extremely important to solving questions such as these:

1) Scope: The argument uses two pieces of evidence (one observation and one experiment during which the inmates' diets were altered and the effects observed) to arrive at a conclusion of causal nature.

Notice how this argument only refers to evidence about A CERTAIN INSTITUTION and the VIOLENT INMATES within this institution. Never does the evidence refer to inmates OUTSIDE of this institution; nor should we infer the same! You can confidently eliminate answers [C] and [D] due their straying too far out of the scope of this argument! "Young offenders" could be part of the institution playing host to the experiment, however, we do NOT know this for certain.

This brings me to another very useful LSAT-tool: Whenever you have an attractive answer choice, ask yourself if you have made any unwarranted or unstated assumptions (usually, this happens subconsciously since we tend to attempt to make assumptions that help prove the particular LSAT question type we are currently solving). This occurs in answer [D]: We cannot assume that the simple stated correlation in this answer choice equates to causation. This is making an assumption that would help us prove our causal conclusion. However, always ask yourself if the unstated assumption which you have just subconsciously made COULD go in the opposite direction! Maybe the nonviolent young offenders in [D] were simply severely obese, making them lethargic and unable to even commit violent acts, and chose to eat nutritious food in order to lose the pounds. Notice how only [A] and [E] mention the violent inmates of this particular institution being studied! This should be a huge clue to eliminate all other answer choices.
Finally, notice the other scope shift from evidence to conclusion. The experiment observed a "STEADY IMPROVEMENT in their behaviour" as the effect. Notice how all the wrong answer choices completely ignore this behavioural change in inmates! Only answer choice [E] mentions this observed improvement.


2) LOCATION of the causal statements within an argument: Its is very important to distinguish this subtle difference! However, LSAT writers frequently use this subtle technique in order to trip up test takers. If the causal statements appear in the PREMISE of the argument, we CANNOT assume any error in the reasoning! We MUST assume that the causal premise is in fact a valid causal argument. However, if the causal statement appears in the CONCLUSION, then we ALWAYS infer that the causal statement is LOGICALLY INVALID! This subtle difference lends itself to solving many assumption-type questions! Notice how this particular question has a causal conclusion. We must assume that this causal conclusion is NOT valid. Thus, we are tasked with strengthening this causal conclusion. On the other hand, if this argument had used this causal statement as EVIDENCE, then we MUST assume that no causal reasoning flaw exists. The flaw of the argument must be something OTHER than causation.


3) Faulty methodology to strengthen/weaken arguments with causal conclusions: If an argument has a causal conclusion, then we must help prove this causation by the usual methods discussed by previous posters above. One common technique by LSAT writers to trap test takers is to have an answer that simply lists another correlation with similar circumstances as the correlation stated in the premise of the argument! These answers are usually extremely attractive and I used to fall for this trap frequently. How could an answer choice that states another correlation of similar nature to the premise in the argument strengthen/weaken a causal conclusion based on this correlation? It NEVER CAN! Notice how [D] does exactly that! It simply lists another correlation (similar to the one used by the argument to prove the causal conclusion) in order to make test takers believe that this would help. However, as stated above, you have most likely made the unstated and faulty assumption in your head that this relationship actually indicates causation in order to help you solve this question. Ask yourself if this correlation could be due to completely unrelated factors...if you're making unwarranted assumptions in order to make an answer choice sound attractive for your cause, it NEVER is the correct answer choice!

Lastly, in order to illustrate the above points, take a look at PT 44 Section 2 #15 ("According to current geological...."). I can almost guarantee that most people would chose [C] due to its extremely attractive nature. However, once again, how can stating a similar correlation to the one used in the premise of the argument strengthen/weaken a causal conclusion? It can't, since we would have to make the faulty assumption that correlation means causation!!!!

[WaltGrace1983]

I think the above discussion is great! I would like to add a few things that I believe are also extremely important to solving questions such as these:

!

FANTASTIC. Really liked what you did here and this helps me a lot. Just for the sake of trying to help, I am going to include my thoughts that I wrote down:

"Violent inmates were placed on high-nutrient diets and their behavior steadily improved over four months
-->
There is a link between poor nutrition and violent behavior"

Question Type: Strengthen

My Thought Process: Here we go again! Correlation and Causation. This argument is saying that, after given some good food for four months while being in an institution, the inmates' behavior increased and - thus - the food was the source. Ok...ummm...how about the fact that they have been in an institution for FOUR MONTHS? Maybe it is true that they got less violent due to a serious look at their behavior. Maybe they get less violent because this instituion has group therapy and counseling. Who knows? However, it is quite a big leap to say that they got less violent because of some food. We would need to compare inmates on different diets and see what the effect is. We are needing to strengthen the conclusion so it would be great to find something about how those people that were not given good food did not improve.

(A) When? Now? Back then? This doesn’t give us enough information. If it said "Some of the violent inmates who took part in the exeperient had committed a large number of violent crimes BEFORE the experiment was conducted" that would not really do anything to the argument. It wouldn't make it any more true that the good food is linked with good behavior. If it said that these violent crimes were committed "DURING" the experiment then that would be a weakener probably. However, there is also a problem in that this answer choice says "SOME" of the violent inmates. How many is some? How many inmates are we experimenting with? What if some = 2 and the experiment is testing 1,000 inmates? This answer choice just leaves too much to the imagination.

(B) So what? We don't care if they are cheaper - this simply doesn't do anything to strengthen the argument

(C) Yea but what if the rest of their diet was high in nutrients and this "low nutrient food" was just an anamoly. I mean look at how vague this is..."low nutrient food" (how much?)..."days before they committed a crime" (so does this mean that having a cupcake 4 days before committing a crime mean the cupcake caused it?"...PUH. LEEZE FOOL.

(D) This is getting somewhere but is not an ideal answer. This is saying that there are some offenders out there who were nonviolent and chose a high-nutrient food. This is great! However, we are talking about different offenders (with potentially different situations) and we are also asserting an argument about high nutrient diet and good behavior. This is not the same as a low nutrient diet and poor behavior. For this, I am going to skip and move on to (E) but kind of thinking that (D) is going to get eliminated.

(E) Correct. Here we have the same group of inmates. They are all violent. Some inmates (those in the stimulus) were put on a good food diet and now they are showing much improvement. Some inmates (those who were not) show no improvement. This gives us more reason to believe that there IS a link between poor nutrition and violent behavior. Why? Because it gives us two worls in which the only differentiating factor is food and, in these two worlds, the behavior is drastically different. If food is the only differentiating factor and their behavior is different then we can more easily (not definitely) assert that food causes behavior.

[hakopis]

@timsportschuetz: However, if the causal statement appears in the CONCLUSION, then we ALWAYS infer that the causal statement is LOGICALLY INVALID!

WaltGrace1983: My Thought Process: Here we go again! Correlation and Causation. This argument is saying that, after given some good food for four months while being in an institution, the inmates' behavior increased and - thus - the food was the source. Ok...ummm...how about the fact that they have been in an institution for FOUR MONTHS?...it is quite a big leap to say that they got less violent because of some food

Loving the discussion but these specific posts helped me see why E is right and more importantly, offered a key takeaway: That a correct answer can strengthen cause/effect statements by showing how the cause had a similar effect, or by showing how a possibly alternative cause did not have the desired effect.

So, when a "causal statement appears in the Conclusion, then it is logically invalid" b/c there exist other possible explanations.

In this case, maybe being "in an institution for FOUR MONTHS" is the cause. (Would be a great weaken answer)

Which is why E works so well. It gets rid of that possibility by saying that, "the OTHER violent inmates in the INSTITUTION, who didn't change their diet, showed NO improvement." (paraphrase)

This answer therefore strengthens the conclusion that Poor Nutrition is a cause of Violent Behavior.
-----------------------------------------------------------------

So I chose (C) b/c I thought seemed to support the idea that: PN --> Violent Behavior. But as mentioned above, it isn't as specific (Young Offenders in general instead of these specific inmates) as we'd like and it doesn't mention Poor Nutrition, just a Low-Nutrient food.

Now, I eliminated (E) b/c of my diagram:

p1: Violent Inmates --> Poor Nutrition
P2: Inmates placed on ~ Poor Nutrition --> Improvements (~ Violent)
C: Poor Nutrition --> Violent Behavior

I thought (E) was an "invalid negation" of P2:

P2: Inmates ~PN --> Improvements
E : Inmates ~~PN --> ~ Improvements

Therefore, we don't know what happened to those inmates who WERE NOT placed on a High Nutrition diet.

I'm questioning whether (1) I diagrammed correctly; and if (2) such line of thinking ("invalid negation/mistaken reversal") are necessary for eliminating answer choices in Causation/Correlation questions.

If you can please shed light on the above questions, I'd greatly appreciate it. Thanks!

[lsatzen]

I just want to re-hash the discussion between answer choices (C), (D), and (E) for my own personal edification. I would love it if an MLSAT Geek could chime in and verify my thinking!

I originally chose (D) during my PT, but chose (E) during BR.

Task: Find an answer choice that helps patch up a flaw or gap that occurs in the argument.

Conclusion:
There is a link between poor nutrition and violent behavior

Support:
1) Violent inmates chose low nutrient foods
2) some violent inmates experienced improved behavior after being placed on high-nutrient diets.

Analysis:
My overly mechanistic approach to causal flaws is what led me astray with this question. After recognizing that we were dealing with a correlation v. causation-type flaw, I ran through my usual mental checklist of how to strengthen causal arguments. In doing so, I forced an interpretation of answer choice (D) to be an example of "no cause ~~> no effect" - which it is not. It is actually a statement of correlation: high-nutrient diet correlated with non-violent offenders.

(C) I eliminated C because we are concerned with the relationship between low-nutrient diets and violent behavior, whereas C is merely discussing a single food item. Further, I'm not sure how directly relevant the time in which a low-nutrient food is consumed factors into the relationship between violent behavior and low-nutrient food.

(D) I had a harder time eliminating (D) in the heat of the moment, because of the incorrect interpretation that I forced. However, upon looking at the answer choice without the pressure of time, the issue with it becomes clear. (D) does not offer any support for the proposed causal link between poor nutrition and violent behavior, because 1) it merely provides more correlation between an irrelevant correlation in the premises, 2) it doesn't relate to the relevant factors in the argument.

(D) is saying "some non-violent people chose high-nutrient diets". That's great, but what does that tell us about people with violent behavior? Nothing. What if it's also true that people who worked out fervently experienced improvement in their behavior, or people who joined a prison gang improved their behavior. All these positive correlations with improved behavior is essentially meaningless unless it tells us something about the how poor-nutrition relates to behavior.

(E) is correct because it shows that when the cause is present the effect is still present.

[ohthatpatrick]

Nice thoughts. I think that the distinction between 'food' and 'diet' is a nice pick-up in (C).

I'm not sure I understood how you were shooting down (D) (or how you disqualified your original assessment).

The author is selling us on the idea that violent behavior goes with poor nutrition, with the flipside being that better behavior goes with better nutrition.

So from a bird's eye view, (D) seems to connect high-nutrient with nonviolent.

An answer doesn't have to be causal to strengthen causality. A further correlation between high-nutrient diet and nonviolent behavior WOULD strengthen the conclusion.

But a correlation means a statistical trend or association.

A correlation is when "people who are X are more likely to be Y than are people who are not X".

(D) doesn't get us anywhere near there. It just says that many people in a study chose high nutrient and were nonviolent.

Okay, well what % is "many"?

We have no idea. "Many NFL players are rich" is probably close to 100% of NFL players. "Many people get hit by lightning each year" is probably close to .001% of the population.

The study in (D) might have results like this:
1000 people chose high-nutrient food
80% (800) of them were violent
20% (200) of them were nonviolent.

Cool - it's still true that "many of them were nonviolent".

Yet these results would actually WEAKEN the argument.

So the easiest way to compare (C), (D), and (E) is just strength of language.

(C) says that at least a few people have consumed a french fry a few days before they committed a violent crime. (So what? First of all, it's only a few people. Secondly, I'm not even convinced they were on a low-nutrition diet. Maybe during the rest of those days, they were eating quinoa, kale, and edamame)

(D) says that at least a few people in a certain study chose a good diet and were nonviolent. (So what? Was there any statistical TREND connecting those two ideas?)

(E) says that ALL the low-nutrient people in the study did NOT show an improvement in behavior. (Wow -- the control group --- looks like the quality of diet really WAS a meaningful variable in terms of improvement of behavior)

Hope this helps.