Parallel/Parallel Flaw Questions

ws81086n
Posts: 318
Joined: Sun Aug 26, 2012 9:47 pm

Parallel/Parallel Flaw Questions

Postby ws81086n » Tue Sep 25, 2012 2:54 am

Very strong in all LR types except P/PF, which I am pathetic at. The most challenging ones can take me up to 4 minutes, and I don't get them right a lot. I am pressed for time on LR, and so I often skip them if they are long/seem hard, which is a profitable strategy at present given my general timing issues and how long it takes me to do them/how bad I am at them. What's the best way to improve on these questions? Obviously drilling them and reviewing the sections on them in top prep books, which I haven't done, but anything else?

vegso
Posts: 67
Joined: Wed Aug 22, 2012 2:08 pm

Re: Parallel/Parallel Flaw Questions

Postby vegso » Tue Sep 25, 2012 3:34 am

get real good at turning things into abstract formal logic quickly

these questions are always gimme's for me see something and turn it into

A->B or C
~C
A->B

then just plug into the variables as you go along, though you do have to keep track of logical force words too, be very aware if your argument is relying on some, most, all etc

ws81086n
Posts: 318
Joined: Sun Aug 26, 2012 9:47 pm

Re: Parallel/Parallel Flaw Questions

Postby ws81086n » Tue Sep 25, 2012 4:03 am

Thanks for the reply. Doing that is definitely not my strong suit right now, but I think reviewing/drilling formal logic will help out a lot. Seems to make sense that out of all the question types, P/PF Q's have the most room for improvement. Or I'm hoping so.

User avatar
cahwc12
Posts: 941
Joined: Mon Jul 02, 2012 4:49 pm

Re: Parallel/Parallel Flaw Questions

Postby cahwc12 » Tue Sep 25, 2012 8:17 am

For parallel reasoning questions, read for the argumentative structure. If the structure doesn't match, it's wrong. While reading for the structure, keep an eye on whether or not the answer choice contains flawed reasoning. If it does, then it's wrong. Then, if you notice any tonal words (most, best, least, some, many, few, all, none, etc) compare those in AC to stimulus. If they are different qualities (some in stimulus, most in AC), the answer is wrong. Lastly, take a look at the conclusions. Maybe the stimulus says "should" whereas the AC says "will" or "doesn't." Often any one of these strategies will knock out two or three ACs.

For parallel flaw questions, there are two types that should concern you--informal and formal. For informal, you're just identifying the flaw like in a regular flaw question, and then matching it to an AC that exhibits the same flaw (part-whole, etc). For formal, you're doing the same as parallel questions, where you match the argumentative structure. Very often the most difficult parallel flaw questions tend to be the easiest flaws (reversal, negation), so keep an eye out for that.

I recommend picking up the cambridge LSAT parallel and/or parallel flaw question packets for drilling. If you decide to get the flaw packet, here's a list of all the questions and their respective flaws that you can refer to:


Parallel Flaw questions (Cambridge Packet)
1 could --> must
2 X is most likely to cause Y, but most X do not cause Y, therefore X is not likely to cause Y.
3 Reversal
4 distinction (petting a pet vs owning a pet)
5 Negation
6 Reversal
7 could --> must
8 Whole-Part
9 lack of evidence --> false
10 part-whole
11 could --> must
12 Reversal and assumption
13 formal-proportion: most A are B ---> All B are A
14 correlation to causation
15 ad hominem (opposite actions)
16 small sample bias
17 proportion
18 Whole-Part
19 formal-proportion: Most A are B, Most A are C ---> Most A are B and C
20 Reversal
21 conclusion is true therefore argument is valid
22 A doesn't cause B. Therefore C will cause B.
23 part-whole
24 Whole-Part
25 Reversal
26 has been --> will be
27 incomplete solution --> not good.
28 ad hominem (opposite actions)
29 formal-proportion: All A are B, some B are C, therefore some A are C.
30 Negation
31 formal-proportion: Most A+ are B, most A- are not B; therefore Most B are A+. Proportion failure
32 "understanding a justification means the justification is valid"
33 Negation
34 lack of evidence --> false
35 formal-proportion: Some A are B, Some B are C, --> Some A are C
36 formal: A --> B; A ---> ONLY B
37 fallacious reasoning fallacy
38 formal-proportion: Most A are B; Most B are C --> Most A are C
39 degree: All A are B --> All very A are very B
40 Reversal
41 degree: A --> B therefore lower A --> lower B
42 could --> must
43 formal: A --> Not B therefore only A
44 most increase --> most overall
45 correlation to causation
46 Negation
47 Incomplete comparison
48 Negation
49 Whole-Part
50 Negation
51 misapplication of odds
52 Whole-Part
53 part-whole
54 Whole-Part
55 formal: A and B --> C therefore A --> C
56 formal-proportion: Some A are not B; All C are A --> Some C are not B
57 false appeal to authority
58 could --> must
59 Negation
60 Incomplete comparison
61 degree fallacy: More A than B --> commit more to A than B
62 part-whole
63 Negation
64 formal-proportion: No A are B; Most A are C ---> Some B are not C
65 formal-proportion: Some A are B, Some B are C, --> Some A are C
66 Reversal
67 correlation to causation
68 incomplete comparison
69 meaning shift
70 Negation
71 what's true of X must be true of a copy of X
72 Reversal
73 Whole-Part

Manhattan LSAT Noah
Posts: 746
Joined: Tue Oct 12, 2010 8:43 am

Re: Parallel/Parallel Flaw Questions

Postby Manhattan LSAT Noah » Tue Sep 25, 2012 10:44 am

ws81086n wrote:Very strong in all LR types except P/PF, which I am pathetic at. The most challenging ones can take me up to 4 minutes, and I don't get them right a lot. I am pressed for time on LR, and so I often skip them if they are long/seem hard, which is a profitable strategy at present given my general timing issues and how long it takes me to do them/how bad I am at them. What's the best way to improve on these questions? Obviously drilling them and reviewing the sections on them in top prep books, which I haven't done, but anything else?

After you digest the stimulus, identify the form/nature of the conclusion (watch out for modifiers and whether the conclusion is a relationship or just a statement) and eliminate any answers that don't match that. Then do the same for the premise. Then, with what's left, get into the nitty gritty of structure.

msmith19
Posts: 38
Joined: Sun Sep 09, 2012 1:33 pm

Re: Parallel/Parallel Flaw Questions

Postby msmith19 » Tue Sep 25, 2012 11:17 am

I can attest to writing out the FL and going from there. I used to do these by 'feel' and was quite accurate but then I realized when it's your last question on the entire test and fatigue is setting in, it's not as easy to abstractly absorb the stimulus and hold multiple elements in your head at once. Write out the FL (see what kind of logical pattern or flaw they are following). Then I compare the quantifiers and qualifiers and whether the statements are positive or negative (this last one is a bit susceptible to error though).

ws81086n
Posts: 318
Joined: Sun Aug 26, 2012 9:47 pm

Re: Parallel/Parallel Flaw Questions

Postby ws81086n » Tue Sep 25, 2012 2:56 pm

Big thanks to everyone for the suggestions. Going to get on all of this soon; starting to think these questions may end up being all bark and no bite.




Return to “LSAT Prep and Discussion Forum”

Who is online

Users browsing this forum: cherrygalore, floatie, govlife, lagavulinjoe, lawcapture, Pozzo and 21 guests