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PLXTDNR
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Re: bp shinners’ semi-weekly office hours

Postby PLXTDNR » Thu May 31, 2012 4:55 pm

bp shinners wrote:
PLXTDNR wrote:Hey there bp - I'm hoping you can explain a rule on games to me -

the dreaded "if and only if."

1) A goes to the party if, and only if, B goes to the party AND

2) If A goes to the party then B goes to the party.

Now, the way it looks to me is in scenario 1, they must go together. A goes to the party if B goes to the party, and does not go to the party without B.

In Scenario 2, it looks like B is free to go to the party without A, but A must have B. (If A then B, if no B then no A)

I think I have that right (but am not sure), but what would the contrapositive for scenario 1 look like?

Thanks!


You've got it exactly right.

If and Only If statements can also be called Must Be Together statements - you either have both, or you don't have either. As such, we write it out as a biconditional:
A<-->B
That way, I know it goes both ways - If A, then B; If B, then A.
The contrapositive (if you want to call it that) is:
NOT A<--> NOT B
If no A, then no B; if no B, then no A

For grouping games, these are unbelievably powerful rules, and they usually lead to scenarios.

The second rule you state is what we call a Tag Along rule, and they're the weakest of the four main types of grouping game rules.

For the record, those rules are:
AT LEAST ONE
-The sufficient condition is negated
-So NOT A-->B is the same as saying you must have A or B (or both, since or is inclusive)
-Shortcut: If the sufficient condition is negated, you must have at least one of the players in the group
-These are unlikely to come up in multi-group grouping games (i.e. the ones with 3 or more groups)

NOT BOTH
-The necessary condition is negated
-So A-->NOT B is the same as saying you can't have both A and B (which is the same as saying NOT A or NOT B, or not both since or is inclusive)
-Shortcut: If the necessary condition is negated, you can't have both of the players in the same group
-These are the most common rule in grouping games

MUST BE TOGETHER
-Usually stated as must be together, or if and only if
-You either have both, or you have neither
-The strongest rule, and the one most likely to lead to scenarios

Tag Along
-Either neither term is negated, or both are (if both are negated, just take the contrapositive and you'll get the traditional-looking tag along)
-Will look like A-->B (or NOT B-->NOT A)
-Weakest rule, doesn't tell you much

There is one time when you can get a stronger rule than Must Be Together, and that's when you have AT LEAST ONE, BUT NOT BOTH. This can either be a single rule, or broken up into two rules. If you get this type of rule, you're golden. This means you should set up two scenarios, based on which one of your two players is in and which one is out. It makes a rough game a lot easier. Just look at the summer school grouping game, where the student has to take 4 of 8 classes (statistics at 3/9, world history, russian, japanese, geography, psychology, mathematics, and yes I did that from memory).


Thank you bp! I am so happy that I have finally crystalized it in my head - the cp you gave makes sense too :) I remember that summer school problem. I love the at least one but not both questions - I rip through those! Your help is much appreciated :)

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dowu
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Re: bp shinners’ semi-weekly office hours

Postby dowu » Thu May 31, 2012 9:42 pm

:shock: :shock:
Last edited by dowu on Sun Apr 17, 2016 11:42 pm, edited 2 times in total.

rglifberg
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Re: bp shinners’ semi-weekly office hours

Postby rglifberg » Thu May 31, 2012 9:54 pm

bp shinners wrote:
rglifberg wrote:Could you go over #21 on section 2 from PT#31, please. Thanks!


The dreaded double flaw parallel flaw question - no one likes these!

The first flaw, I believe, is pretty obvious. We're given a rule (deposits are credited that day only when made before 3). I'd diagram that as:
DC->3PM- (if the deposit is credited that day, it was made before 3PM)
because 'only when' introduces the necessary condition.

Then, we're told that Alicia knows the deposit was made before 3PM. Well, that doesn't guarantee that the deposit was credited that day, because being deposited before 3PM is a necessary condition to being credited that day, but not a sufficient condition. So the first fallacy is a sufficient/necessary condition fallacy - we're given the necessary condition, and we conclude the sufficient. We can't do that.

The second flaw is much more subtle, and much harder to spot. I've still got my rule above. I also still know that Alicia knows the deposit was made before 3PM. From that, I conclude she knows that the deposit was credited that day (I know that's my conclusion because of the "So,..." at the beginning of that sentence, which is a tell-tale sign of a conclusion). Well, here's the problem with doing that - I'm never told that Alicia knows the rule about when deposits need to be made in order for them to be credited that day. Alicia might have no idea about the bank's rules, and all she really knows is that she stopped by the bank and dropped a check off at 2:54 PM. My argument is assuming that Alicia knows the rule and was applying it to her actions (incorrectly, I might add, as we already talked about the sufficient/necessary fallacy she was falling into if she did know the rule and did think it was definitely credited that day). I don't know if I'd classify that as a specific type of flaw - I'd probably throw it under the catch-all of "Unwarranted assumption."

So I need to find an answer that both messes up sufficient/necessary conditions, and also assumes that someone knows something that I'm not told they know.

A messes up sufficient and necessary, but it doesn't assume knowledge on anyone's part.
B is wrong for exactly the same reason as A.
C is the correct answer. We mess up sufficient and necessary conditions (it's necessary for Helen to resign for George to be promoted, but it's not sufficient), and we also assume that George knows that he's in line for the promotion if Helen resigns. Bingo bango.
D isn't even flawed, so it can't be right (if John believes that 4 is a prime number divisible by two, he believes that such a number exists).
E is an exclusivity fallacy - just because something shares two features, and someone wants one of those features, it doesn't mean they want the other. Pat could want to become a social worker in spite of the poor pay, not because of it.

Hope that helps!


Wow, thanks! That makes perfect sense now. I noticed the first flaw but not the second one.

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Re: bp shinners’ semi-weekly office hours

Postby TunnelVision » Thu May 31, 2012 10:42 pm

Hey BP,

How should I approach analogy questions in RC? I really struggle with these. Also, and this may be a silly question to ask, but do you have any tips for eliminating "dumb mistakes"? I've noticed that I tend to miss some of the easiest questions in LR by either overanalyzing the stim or forgetting about some small detail that turns out to be relevant. For example, PT61 S4 Q8 I picked C because I basically said "ok let's say the asteroid caused dinosaurs to go extinct." I saw C and thought this definitely weakens the argument, and I even read E but it's almost as if once I select an answer I'm overconfident sometimes. The reason I got this wrong was because I neglected the word "most" as in most exinctions, and basically forgot about everything after the conlcusion and "worldwide effect." My LR is about -5 to -6 comined now, with half of my misses coming from the first half of the section usually.

ilovethelaw
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Re: bp shinners’ semi-weekly office hours

Postby ilovethelaw » Fri Jun 01, 2012 1:33 am

Flaw help...thanks!

1) I really have trouble with Flaw questions in LR. A lot of my mistakes in LR are routinely Flaw questions. I read the question first, so I know its a Flaw. I know most of the general flaws that come up (whole-to-part, correlation equals causation, etc), and can eliminate answer choices that state a Flaw that was not present (i.e. ad-hoc attack), so if it is an obvious example of those clear-cut ones then they are easy. But, sometimes I read the stimulus and can't state exactly what the flaw is/I don't even think it's flawed...is every flaw able to be grouped, and so i just need to be able to recognize that it is a variation of something else? Do you have any general tips for attacking flaw questions, and what to do if I can't easily prephrase an answer? I find that I am often "spinning the wheels" on Flaw question.


As for specific questions:

2) PT6, S3, Q8. I was debating between B and D, and incorrectly chose B. Can you clarify this? I read the stimulus and thought: ok, WA-> not O. but people say that Obscene WA does exist. But the response is that if it really was O, then its not WA.
I wrote down "claim that WA->O, response is O->not WA" and so I thought that B was correct since it is a contradiction?

3) PT11, S4, Q17. I got B as the correct answer, since the teacher explicitly says "in which they were made".
but I was wondering why D can't work as well. In fact, when I prephrased it, I thought it would be a straw man flaw since the student starts off by saying "but what you are saying then, is.." and the wording of D seems to be for a straw man attack. And isn't that true? The student is "judging the merits of the teachers position" (i.e. saying the position sucks) because of its ridiculousness in an extreme situation (i.e. you dont need to protect your source because you can just make it up). in this case I chose B over D since it required less of a leap in assumptions. But did I misunderstand what choice D is saying?

4) PT13, S2, Q24. I don't see how there is an error at all. If only 1 out of 100 times it alerts when there actually was no explosive, then than means the other 99 alerts were correct and there is an explosive, no?

MissJenna
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Re: Patterns in LR!!!!

Postby MissJenna » Fri Jun 01, 2012 11:39 am

Okay...my question is a little more general. It has to do with pattern recognition in LR. I posted a thread about this but only got 1 response.

I really don't know where to begin so I'm just going to write whatever comes to my mind. What should I look for when trying to find patterns? Can you PLEASE give me some SPECIFIC examples of patterns you've seen and/or seen other people find.

Are there patterns within specific question types (e.g.,- flaws, assumptions, etc.,) or are there patterns just overall that I should notice in the LR section??

Basically I am NOT seeing any patterns in LR. Maybe it's because of the fact that I'm all over the place or maybe it's because I find LR just so damn difficult that it's hard for me to notice anything.


Please help.

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bp shinners
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Re: bp shinners’ semi-weekly office hours

Postby bp shinners » Fri Jun 01, 2012 12:01 pm

And we're live.

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shifty_eyed
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Re: bp shinners’ semi-weekly office hours

Postby shifty_eyed » Fri Jun 01, 2012 12:04 pm

Biggest score improvement you've observed IRL?

How did they do it?

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dowu
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Re: bp shinners’ semi-weekly office hours

Postby dowu » Fri Jun 01, 2012 12:07 pm

shifty_eyed wrote:Biggest score improvement you've observed IRL?

How did they do it?


I'd like to know the answer to this as well.

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timmydoeslsat
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Re: bp shinners’ semi-weekly office hours

Postby timmydoeslsat » Fri Jun 01, 2012 12:09 pm

So this is something that I have recently come across and wanted your take on it.

When you have a situation of:

A ---> B
B
_____________
A

(1) The argument mistakes a sufficient condition for a necessary condition
(2) The argument mistakes a necessary condition for a sufficient condition

To me both answer choices are valid. The answer choice could be talking about how variable A, which is a suff condition, is being confused for a necessary condition of B's existence, as the arguer concludes that A must happen due to B happening. While at the same time, the other answer choice can talk about B is given as necessary condition of A's existence and it is not being confused that B is actually sufficient to bring about A.

I have been told that both answer choices are correct. I would just like confirmation.

Thank you

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Re: bp shinners’ semi-weekly office hours

Postby honeycomb » Fri Jun 01, 2012 12:12 pm

For the longest time LG was bringing down my score. I would get around -1 to -2 on each LR, -3 on RC, and -8 on LG. I drilled day in and day out and I'm finally at the point where I am getting -0 to -1 on LG. Good news, right? Right. Except for the fact that now my LR has dropped and my score is exactly the same.

I have been finishing my LR sections with about 6 minutes left and I've been getting around -4 on each one. My mistakes are always in the beginning of the section, which makes me think that this is a timing issue; maybe I'm rushing through the beginning. There is no particular type of question giving me trouble.

Do you have any suggestions for some time benchmarks to set in an LR section? Or any other advice for that matter? I have two PTs this weekend and I want to try a new LR strategy to see if that fixes my problem.

My RC scores have dropped a bit too, but I'm thinking (hoping) that it's just because I've neglected RC a bit and after drilling a few more sections I'll get back to where I was.

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bp shinners
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Re: bp shinners’ semi-weekly office hours

Postby bp shinners » Fri Jun 01, 2012 12:24 pm

nmop_apisdn wrote:PT60, S3, Q18, I chose answer A. I initially eliminated B, C and E, leaving me to choose from A & D.


You missed an important keyword in the stimulus - EACH person who bears that risk. I need an answer that specifically states that the risk I'm talking about is limited just to the person assuming it. A doesn't do this (the safety features could help others survive an accident); D also doesn't do this, as it only talks about people who drive vehicles; however, others might be impacted by these health risks. C is the only answer that limits the risk to who we're talking about, by saying the risk we're talking about is the fatal injury to that driver.

PT60, S3, Q19, I chose answer C. I initially eliminated B, D and E, leaving me to choose from A & C.


Should have gotten rid of A because this isn't an exclusivity fallacy with regards to the theories - we don't say that you can only pick one theory, so the other must be false. Instead, we did a study that the author thinks disproved one of those theories. So the fallacy has to be in regards to why that study doesn't, in fact, disprove that theory (the chemical one).

In general, if you can't diagram the stimulus for a flaw question, don't pick the sufficient/necessary answer choice. Not always going to be right that way, but it should at least make you think twice about it.

Definitely D here - we tested each compound individually. Maybe they're only toxic when you combine them (SCIENCE!). Whenever I do a study on the LSAT, make sure that it mirrors the conditions in the real world. Here, we don't - they ate only part of the sea butterfly's toxic goo at a time. I'm guessing sea predators aren't picky eaters, and they wouldn't cut up the butterfly before eating it.

PT60, S3, Q20, I chose answer C. I initially eliminated A, D and E, leaving me to choose from B & C.


I'm trying to add a piece of information that lets me know that Jarrett really shouldn't have criticized Ostertag's paper. I know he should have criticized only if it won't hurt Ostertag and he criticized hoping to benefit someone. None of my answers talk about hurting Ostertag, so let's put that aside for a second. We have to deal with the hoping that it will benefit someone else. I know that it didn't benefit anyone else; however, Jarrett could be dumb; he might have thought it would benefit someone else. If that's the case, then he's still OK based on my principle (because he criticized HOPING it would help someone else). I need an answer that lets me know that he did not, in fact, think it would benefit anyone if I want to justify saying his criticism wasn't OK. That's answer choice A.

Whenever the LSAT qualifies a condition (here, by saying that it's hoped that we benefit someone), that qualification is going to be important. It's also going to trick most people.

PT60, S3, Q21, I chose answer D. I initially eliminated A, D and E, leaving me to choose from B & D.


I'm trying to strengthen the idea that minivans aren't inherently safe; rather, they have safer drivers (soccer moms). D, if anything, weakens that because it lets me know that minivans are inherently safer - bigger vehicle=safer.

I'm actually surprised you didn't go for C, which is the most common incorrect answer.

E gives me an explanation for why minivans aren't inherently safer - they don't handle well. Not only does this eliminate a possible explanation (the tests were poorly designed and they actually are inherently safer), but matched up with our data that they have less injuries, makes it even more likely that safe drivers are behind the wheel because there are fewer injuries despite handling poorly, suggesting the drivers are even better than I thought (since they're making up for the poor handling).

PT60, S3, Q22, I chose answer C. I initially eliminated A, B and D, leaving me to choose from C & E.


C is way too broad for a necessary assumption question, especially one talking about a specific set of facts here. I know that in this case increased demand led to an increase in cost, but I don't know that that's a general rule that will always be followed.

Also, in this one, I talk about responsibility in my conclusion, but not in my premises. Every single time that happens in either assumption-type question (maybe a few exceptions, but it's a pretty strong rule), the answer will have to deal with that new concept in the conclusion. So A and B are really my only possible answers.

A talks about indirectly causing something; B talks about unforeseen consequences. Well, I know that they indirectly caused the increase (they didn't add a tax onto the cost, so it wasn't a direct increase); I don't know if the price increase was foreseen or not. So A's gotta be it.

Between all of these, I think you're commonly skipping over words that carry a lot of weight on the LSAT but not in everyday life. When studying for the LSAT, you train yourself to catch the common keywords like can/might/all/never/most/etc... However, as more people prep for the LSAT, they have to get trickier with how they use words. As such, they're starting to use other keywords to indicate a variety of certainty and logical strength. For instance, hoping is a word that most will gloss over, but it's just as important and believe (which is another tricky one) as far as the person's mental state when making their decision. Independent is another one that they keep using - completely independent is redundant, because the 'completely' is wrapped up in independent. What I'm trying to say is it's a strong word.

So don't skim over the stimuli, and don't skip over words that indicate strength/mental state/certainty, even if they're not traditional words. I think that should help you with some of these harder questions.

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Re: Patterns in LR!!!!

Postby MissJenna » Fri Jun 01, 2012 12:25 pm

MissJenna wrote:Okay...my question is a little more general. It has to do with pattern recognition in LR. I posted a thread about this but only got 1 response.

I really don't know where to begin so I'm just going to write whatever comes to my mind. What should I look for when trying to find patterns? Can you PLEASE give me some SPECIFIC examples of patterns you've seen and/or seen other people find.

Are there patterns within specific question types (e.g.,- flaws, assumptions, etc.,) or are there patterns just overall that I should notice in the LR section??

Basically I am NOT seeing any patterns in LR. Maybe it's because of the fact that I'm all over the place or maybe it's because I find LR just so damn difficult that it's hard for me to notice anything.


Please help.



Btw BP....will you do something like this again?

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bp shinners
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Re: bp shinners’ semi-weekly office hours

Postby bp shinners » Fri Jun 01, 2012 12:32 pm

TunnelVision wrote:Hey BP,

How should I approach analogy questions in RC? I really struggle with these. Also, and this may be a silly question to ask, but do you have any tips for eliminating "dumb mistakes"? I've noticed that I tend to miss some of the easiest questions in LR by either overanalyzing the stim or forgetting about some small detail that turns out to be relevant. For example, PT61 S4 Q8 I picked C because I basically said "ok let's say the asteroid caused dinosaurs to go extinct." I saw C and thought this definitely weakens the argument, and I even read E but it's almost as if once I select an answer I'm overconfident sometimes. The reason I got this wrong was because I neglected the word "most" as in most exinctions, and basically forgot about everything after the conlcusion and "worldwide effect." My LR is about -5 to -6 comined now, with half of my misses coming from the first half of the section usually.


Analogy questions in RC should be approached in the exact same was as non-diagrammable parallel questions for LR. The burden for a correct answer choice is extremely high, and everything has to match up. For Parallel questions, our method involves coming up with a motto, or a principle, that describes the argument abstracted from the topic. You can often appropriate an idiom ("a bird in the hand is worth two in the bush") for this. Often, they'll ask you to analogize a study/experiment. If that's the case, make sure that all elements (groups, results, etc...) are the same between the two, and make sure that any artificial element is artificial in the answer choice as well.

My advice would be to underline the conclusion and then check your answer against it before you fill in the bubble. Also, it can help to circle the important keywords - most is something that should ALWAYS catch your eye. In this case, the argument itself concedes that some dinos were probably killed by the meteor - a qualification of the author's conclusion that the meteor didn't cause dino extinction. A qualification to a conclusion is always going to play an important role in an LR question. So C doesn't tell me anything the argument didn't already admit; and I should have gone into the answer choices knowing that they were going to give me that one as a sucker choice (qualified conclusions always have a sucker choice relating to that qualifications).

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bp shinners
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Re: bp shinners’ semi-weekly office hours

Postby bp shinners » Fri Jun 01, 2012 12:57 pm

ilovethelaw wrote:1) I really have trouble with Flaw questions in LR. A lot of my mistakes in LR are routinely Flaw questions. I read the question first, so I know its a Flaw. I know most of the general flaws that come up (whole-to-part, correlation equals causation, etc), and can eliminate answer choices that state a Flaw that was not present (i.e. ad-hoc attack), so if it is an obvious example of those clear-cut ones then they are easy. But, sometimes I read the stimulus and can't state exactly what the flaw is/I don't even think it's flawed...is every flaw able to be grouped, and so i just need to be able to recognize that it is a variation of something else? Do you have any general tips for attacking flaw questions, and what to do if I can't easily prephrase an answer? I find that I am often "spinning the wheels" on Flaw question.


Ah, flaw questions. The bane of many a student. Especially since almost all questions are some variation of a flaw question (that's my theory, at least).

For the most part, you can group the flaws into one of those categories (sometimes more than one). However, there are a few times (generally, the trickier ones) where the flaw can really best be understood as an unwarranted assumption, which is just another way of saying a flaw.

If you can't figure out which flaw it is, there are two ways to approach it:
1) Use elements of the premises/conclusion to determine what flaw type is likely. For instance, if you have a really strong conclusion, or a conclusion that recommends one course of action, it's probably an exclusivity fallacy. If you diagrammed the stimulus, it's probably a sufficient/necessary fallacy. If your conclusion is about a member of a group or a group, you probably have a composition fallacy. If you have a study done, it's probably a sampling fallacy. If you have a percentage anywhere in the stimulus, it's probably percentage vs. amount. If you're talking probabilities, it's probably temporal (you're making a prediction of the future based on events in the past, like a roulette wheel). If you conclude that the opposite of someone else's theory is true/false, you probably have an absence of evidence fallacy. If you laughed during the stimulus, you probably have an ad hominem fallacy. If you can underline two sentences that say exactly the same thing, you have circular reasoning (the argument assumes what it purports to establish) - and this is the only time you have circular reasoning. If you compare two things, you probably have a comparative fallacy. If there are quantifiers/modal words (other than never/always, which is probably an exclusivity fallacy), it's probably a logical force fallacy. If you have the words 'thinks' or 'believes' or anything similar, it's probably a perception vs. reality fallacy. If you have a new term show up in the conclusion, it's probably an equivocation. I think that's all of them, but I'm doing this from memory.
2) If you still can't figure it out, try this trick. Say "Even if (premises), it might not be the case that (conclusion)." If you can explain the world in which that statement is true, you'll have your flaw. You may have to go from your specific example of the world where it's not true to a general statement of the flaw, but it should be a lot easier once you've explained a world in which that conclusion doesn't follow from the premises.

2) PT6, S3, Q8. I was debating between B and D, and incorrectly chose B. Can you clarify this? I read the stimulus and thought: ok, WA-> not O. but people say that Obscene WA does exist. But the response is that if it really was O, then its not WA.
I wrote down "claim that WA->O, response is O->not WA" and so I thought that B was correct since it is a contradiction?


You've got the senator's claim right: WA-> NOT O
His response to the counterexamples, however, is O->NOT WA
I don't care what the other people say, because they're not part of the Senator's argument.
Here, the Senator has a general rule, and his response to the counterexamples is to repeat that same general rule (well, the contrapositive of it). Since I can underline the Senator saying the same thing twice (a statement and its contrapositive are the same statement), I've got a circular argument, so D's my answer.

When you wrote down "claim that WA->O, response is O->NOT WA", you neglected to assign those views to different parties. For someone to have a contradictory belief, they have to hold all parts of that contradictory belief. Here, the contradiction is between how others characterize these pieces (as obscene works of art) and how the senator does (obscene non-works of art).

When there exists more than one viewpoint in the stimulus, be very careful to separate the premises into which VP is holding that to be true.

3) PT11, S4, Q17. I got B as the correct answer, since the teacher explicitly says "in which they were made".
but I was wondering why D can't work as well. In fact, when I prephrased it, I thought it would be a straw man flaw since the student starts off by saying "but what you are saying then, is.." and the wording of D seems to be for a straw man attack. And isn't that true? The student is "judging the merits of the teachers position" (i.e. saying the position sucks) because of its ridiculousness in an extreme situation (i.e. you dont need to protect your source because you can just make it up). in this case I chose B over D since it required less of a leap in assumptions. But did I misunderstand what choice D is saying?


But the position of the teacher doesn't apply to just making it up. She's very specific in that she's talking about hiding sources. The student takes that past its credible limits into a world where journalists are just sitting around, quoting no one. You have to deal with the arguments as they're written, and here the teacher clearly states that these journalists are quoting sources, not making it up.

4) PT13, S2, Q24. I don't see how there is an error at all. If only 1 out of 100 times it alerts when there actually was no explosive, then than means the other 99 alerts were correct and there is an explosive, no?


Nope. Let's look at what's going on here, because they're messing with the percentages.

We send a ton of luggage through that scanner. We know that, when there are no explosives present, an alarm goes off ~1% of the time. That means for every 100 pieces of luggage, I get 1 false positive, for every 1000, I get 10, etc...

However, it tells me nothing about how often an actual positive - an alarm goes off when there is explosives - happens. It could be that only 1 time out of a million is there actually an explosive in a piece of luggage (that's probably even a high percentage of the time).

So let's do the math: I put 1,000,000 pieces of luggage through the machine. Since 1/100 times I get a false positive, that means the alarm will go off 10,000 when there is no bomb present. However, if you use my completely made up 1/1,000,000 for the rate of actual bombs, you'll have 1 real bomb. That's much different than the 99% of the alarms that the stimulus makes.

Is it a problem that I just made up a number to test it? No, because the stimulus doesn't tell me that info, so my 1/1million is a possible rate. I've now created a world where the conclusion doesn't follow from the premises (in this case, because they're switching which groups they're referring to when they talk premise percentage and conclusion percentage - premise percentage is based on luggage evaluated, whereas conclusion percentage is talking about luggage that triggered the alarm; different groups, so the percentages don't carry over). Since I now know why the conclusion doesn't work, I can abstract (to my parenthetical from the previous sentence) and find the answer.

Or, I can shortcut it and see that I'm talking numbers and percentages, and I can almost never do that, so I pick the % vs. Amt. fallacy in answer choice E.

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bp shinners
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Re: Patterns in LR!!!!

Postby bp shinners » Fri Jun 01, 2012 1:00 pm

MissJenna wrote:Are there patterns within specific question types (e.g.,- flaws, assumptions, etc.,) or are there patterns just overall that I should notice in the LR section??


There are patterns within specific question types. For the flaws one, see the post I made immediately before this about features of the stimulus that suggest specific flaws.

Other patterns:
What is generally diagrammable? Must be True questions, Parallel questions, Sufficient Assumption questions, principle Soft Must Be True questions ("Which of the following most closely conforms to the principle stated above)
What question types do I generally want a weak answer choice? Non-diagrammable Must be True questions, Soft Must Be True questions (any MBT question with qualifying language in the prompt, like MOST strongly supported), Necessary Assumption questions
What questions types do I generally want strong answer choices? Must Be False, Sufficient Assumption

There are a ton of patterns in there, but they're a little hard to suss out at times. However, those should get you started on what you should be looking for when you look for patterns!

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bp shinners
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Re: bp shinners’ semi-weekly office hours

Postby bp shinners » Fri Jun 01, 2012 1:04 pm

shifty_eyed wrote:Biggest score improvement you've observed IRL?

How did they do it?


Biggest improvement I saw was from an ~144 (I forget the exact number) to a 174. The kid worked through the entire BP curriculum and also went through the PS Bibles at the same time. We talked about the differences between the two and he started to understand the underlying logic that led to both methods working. That's how you break the 170 barrier - not just knowing the methods/shortcuts/tricks, but understanding why they work (and, thus, in which situations they won't work).

He was a sophomore in a joke major - barely went to class, just prepped for the LSAT constantly. He was putting in a lot more time than I'd recommend, but I also don't generally see a 30 point score increase, so...

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Re: bp shinners’ semi-weekly office hours

Postby bp shinners » Fri Jun 01, 2012 1:07 pm

timmydoeslsat wrote:So this is something that I have recently come across and wanted your take on it.

When you have a situation of:

A ---> B
B
_____________
A

(1) The argument mistakes a sufficient condition for a necessary condition
(2) The argument mistakes a necessary condition for a sufficient condition

To me both answer choices are valid. The answer choice could be talking about how variable A, which is a suff condition, is being confused for a necessary condition of B's existence, as the arguer concludes that A must happen due to B happening. While at the same time, the other answer choice can talk about B is given as necessary condition of A's existence and it is not being confused that B is actually sufficient to bring about A.

I have been told that both answer choices are correct. I would just like confirmation.

Thank you


The LSAT is going to give you (2) The argument mistakes a necessary condition for a sufficient condition. Your explanation for (1), while technically correct, isn't going to be what the LSAT asks. And if both are given as answer choices, go with (2) - they seem like they're flipsides of the same coin (if the argument assumes that B is sufficient for A, then it also assumes that A is necessary for B). However, I would argue that a better way to characterize the flaw is that it's assuming B is sufficient for A (since B is the premise, and from that it's concluding A).
Last edited by bp shinners on Fri Jun 01, 2012 1:13 pm, edited 1 time in total.

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bp shinners
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Re: bp shinners’ semi-weekly office hours

Postby bp shinners » Fri Jun 01, 2012 1:10 pm

honeycomb wrote:Do you have any suggestions for some time benchmarks to set in an LR section? Or any other advice for that matter? I have two PTs this weekend and I want to try a new LR strategy to see if that fixes my problem.


I wouldn't necessarily set timing benchmarks to slow myself down, as I think if you do that, you're just going to overthink some of those questions and maybe change your answer even more. What I would do is come up with a few extra steps to do to slow yourself down for them and get the easy points. Stuff like always underlining the conclusion, circling logical force words, etc... will slow you down a bit, and possibly stop you from making a stupid mistake like not focusing on a word like 'can'. Also, always read your conclusion against the answer choice before filling in the bubble. It takes about 7 seconds, but it will quite often highlight a stupid mistake you're making.

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Re: Patterns in LR!!!!

Postby bp shinners » Fri Jun 01, 2012 1:11 pm

MissJenna wrote:Btw BP....will you do something like this again?


I'll be here every Tuesday from 4-8 and Friday from 12-4, EST (unless I'm on vacation, in which case I'll make sure to post that).

meandme
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Re: bp shinners’ semi-weekly office hours

Postby meandme » Mon Jun 04, 2012 10:42 pm

Hey BP
I have been doing MBT questions. I seem to get the right AC on questions with argument but can't seem to do much with just a set of facts. I kind of get lost. With the argument I know to look for the conclusion and related the premises but when I am just give a set of statements I am stuck.

Thanks
God bless

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Re: bp shinners’ semi-weekly office hours

Postby ilovethelaw » Tue Jun 05, 2012 12:08 am

RC: PT29, Passage 2, Q22. I was between choice C and D, and eliminated D because it says "ought most to concern themselves" and thought this was too strong. The argument is that they don't help with certain questions, but I couldn't find support for such a claim that they are the issues that both "MOST" and "OUGHT" to concern.

isnt that too strong/unsupported? i crossed it off immediately due to language cues

PT49, Passage 3, Q15. Answer E says "explicitly" refers. But i thought that Galen and Pliny didnt explicitly say they were citing women, and rather just left it ambiguous, and thus that omission leads to the inference that there were women.

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Re: bp shinners’ semi-weekly office hours

Postby shifty_eyed » Tue Jun 05, 2012 12:48 pm

Hi BP,

Could you please explain B vs. A in PT 63 LR1 #22? It seems this type of question pops up frequently, and I never know which of the two to choose. A similar question that I got right, but also was unsure about was #11 on PT 63 LR2 (section 3).

Also, could you please explain why B is wrong on PT 63 LR3 #22? I thought it could be B because the stimulus doesn't seem to me worded to require that saving someone's life always be beyond what could be reasonably expected of a police officer. Are we to assume that if in one case, saving a child's life from drowning exceeds reasonable expectations, this must be true in all cases?

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bp shinners
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Re: bp shinners’ semi-weekly office hours

Postby bp shinners » Tue Jun 05, 2012 2:20 pm

meandme wrote:Hey BP
I have been doing MBT questions. I seem to get the right AC on questions with argument but can't seem to do much with just a set of facts. I kind of get lost. With the argument I know to look for the conclusion and related the premises but when I am just give a set of statements I am stuck.

Thanks
God bless


First off, it's very, VERY rare for there to be a MBT question that has an argument. Most of those argument-like MBT questions give you a bunch of premises and ask you to draw the conclusion; I wouldn't classify that as an argument, though.

For the ones that are just sets of facts, treat it almost like a Logic Game when you're looking for deductions. There are going to be similar concepts in multiple premises. You should find a way to combine them. One of the combinations of these premises will be the correct answer. This works even if you can't diagram it, though it is a little tricky.

Do you have any specific ones you want me to look at and walk you through to discuss this strategy?

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Re: bp shinners’ semi-weekly office hours

Postby bp shinners » Tue Jun 05, 2012 2:42 pm

ilovethelaw wrote:RC: PT29, Passage 2, Q22. I was between choice C and D, and eliminated D because it says "ought most to concern themselves" and thought this was too strong. The argument is that they don't help with certain questions, but I couldn't find support for such a claim that they are the issues that both "MOST" and "OUGHT" to concern.

isnt that too strong/unsupported? i crossed it off immediately due to language cues


First off, generally you'd be in good shape by crossing an answer off because it's too strong.

However, in this case, I have the following statement: "This is a serious deficiency, since court records are of vital importance in discovering how the law actually affected women, as opposed to how the law was intended to affect them or thought to affect them." That statement has strong language, and additionally it goes on to say that these questions are the ones that need answering. That's enough to get to 'ought most'.

In short, when I see a statement with very strong language in a passage, I make a note of it because it's going to affect my ability to pick a strong answer choice.

PT49, Passage 3, Q15. Answer E says "explicitly" refers. But i thought that Galen and Pliny didnt explicitly say they were citing women, and rather just left it ambiguous, and thus that omission leads to the inference that there were women.


They didn't give biographical information, which is different from saying whether they explicitly cited women. If I cited Dr. Elizabeth Feelgood in a modern work, you wouldn't need me to provide biographical information in order for you to know that I explicitly cited a woman.

The passage also states: "Also pointing to a wider medical practice are the references in various classical medical works to a great number of women’s writings on medical subjects." That's explicitly stating that we cited women's writings on medicine.


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