Game #1 of LGB Grouping ch. what method would you have used?

TiberiusTyrone
Posts: 9
Joined: Sun Dec 25, 2011 9:14 pm

Game #1 of LGB Grouping ch. what method would you have used?

Postby TiberiusTyrone » Sat Mar 24, 2012 1:29 pm

...or if you don't have LGB, it is PT 20, Game #2.

So, I've been learning some methods of how to solve grouping games. I've gone through the LGB and now I've just learned the Logic Tree from Manhattan. I'm wondering for anyone who has used both methods, which one would you have used here... the powerscore method or the logic tree method? It's an in/out closed game, but I had some difficulty using the logic tree with it since the first condition can't be put into the tree.

Okay, so I've only just finished the chapter on how to use the logic tree, so I'm not that proficient...

In your opinion however, what's your take on Manhattan's logic tree? It felt good when I was learning it and it worked well with Game #5 in the Grouping Games chapter of LGB (but this was an in/out OPEN game), but I felt I was taking too much time with Game #1 (a closed game).

MLBrandow
Posts: 129
Joined: Wed Mar 15, 2006 5:12 pm

Re: Game #1 of LGB Grouping ch. what method would you have used?

Postby MLBrandow » Sat Mar 24, 2012 4:18 pm

TiberiusTyrone,

After giving it a fair trial, I feel that Manhattan's logic tree can be as efficient as writing the rules, but can never be more efficient than doing so. If it helps you to write far more than is necessary, then it indicates you require more practice with these types of games. I also attended a free study session where this method was introduced, and I figured if the merits of this method could be shown to be better than simply writing rules, a game would be shown where that holds true. The game that was covered (I can't recall specifically) I solved in 3 minutes, which is about the time you'd be starting the questions by efficiently using their method.

By constructing Manhattan's Logic Tree, you are in essence outlying almost every possibility. How often is this ever the optimum path to solving the game? On occasion, one can construct one or two hypothetical diagrams which may solve the game, but these games are not only rare across all released PTs, but I don't recall one existing in the modern (post-PT40) era. I could be wrong because I haven't seen every LSAT, but there is a clear de-emphasis on games that are solvable by the initial rules alone. I mention this because only when these games are solvable via one or two templates (and sometimes three) is it worth spending so much time diagramming possibilities. The logic tree diagrams every possibility and every possible connection. Moreover, it reveals only what is already revealed in the initial conditional statements you could write in mere seconds. Learning to process conditional statements (and their contrapositives) is integral to a top score on the LSAT, and if you have these skills, the tree is not only useless, but time-consuming. Essentially, if you need this method to help you, I contend that you simply lack the level of understanding that better test takers have. Finally, Manhattan even contends that for some games, it is difficult to know whether you can apply this method effectively or not. This is not a general method one can always use to attack grouping games with conditional logic, whereas diagramming the rules will always benefit you.

Powerscore, by comparison, advocates something similar in that they recommend writing out every contrapositive to conditional rules, such as those in game 20.2. However, if instead you simply learn to read a conditional statement backwards, writing the contrapositive would only waste time. Further, whenever you "check the rules" for any given question, you essentially see every rule twice (since a conditional and its contrapositive convey the same set of information). This redundancy wastes time, as you check a possible answer against two sets of the initial rules.

These partially defined or undefined games typically give many test takers the most trouble because of their use of and reliance on conditional logic. However, I've found that merely writing the rules exactly as they are and heading straight into the questions is the most time-efficient and accurate way to solve these games. Only spend additional time combining rules that are irresistibly obvious (A --> B, B --> C). And if you combine rules, try to avoid writing them twice (independently and combined).

In sum, I don't believe either Powerscore's approach or Manhattan's approach to game 20.2 deserves special consideration, and instead prefer to write the rules as they are. This allows maximum time for actually solving the questions. Time spent on the stimulus and setup is time away from the questions, which are what net you points. If you construct hypothetical diagrams and logic trees in addition to your main diagram and/or rules, you must be certain that it will not just mitigate time spent on questions, but decrease your overall time spent on the game. I have almost never found this to be the case, except in older games that are solved with key deductions (those games which have not been in fashion on the LSAT in well over a decade).

Hopefully this helps and good luck!

TiberiusTyrone
Posts: 9
Joined: Sun Dec 25, 2011 9:14 pm

Re: Game #1 of LGB Grouping ch. what method would you have used?

Postby TiberiusTyrone » Wed Mar 28, 2012 4:26 pm

MLBrandow wrote:TiberiusTyrone,

After giving it a fair trial, I feel that Manhattan's logic tree can be as efficient as writing the rules, but can never be more efficient than doing so. If it helps you to write far more than is necessary, then it indicates you require more practice with these types of games. I also attended a free study session where this method was introduced, and I figured if the merits of this method could be shown to be better than simply writing rules, a game would be shown where that holds true. The game that was covered (I can't recall specifically) I solved in 3 minutes, which is about the time you'd be starting the questions by efficiently using their method.

By constructing Manhattan's Logic Tree, you are in essence outlying almost every possibility. How often is this ever the optimum path to solving the game? On occasion, one can construct one or two hypothetical diagrams which may solve the game, but these games are not only rare across all released PTs, but I don't recall one existing in the modern (post-PT40) era. I could be wrong because I haven't seen every LSAT, but there is a clear de-emphasis on games that are solvable by the initial rules alone. I mention this because only when these games are solvable via one or two templates (and sometimes three) is it worth spending so much time diagramming possibilities. The logic tree diagrams every possibility and every possible connection. Moreover, it reveals only what is already revealed in the initial conditional statements you could write in mere seconds. Learning to process conditional statements (and their contrapositives) is integral to a top score on the LSAT, and if you have these skills, the tree is not only useless, but time-consuming. Essentially, if you need this method to help you, I contend that you simply lack the level of understanding that better test takers have. Finally, Manhattan even contends that for some games, it is difficult to know whether you can apply this method effectively or not. This is not a general method one can always use to attack grouping games with conditional logic, whereas diagramming the rules will always benefit you.

Powerscore, by comparison, advocates something similar in that they recommend writing out every contrapositive to conditional rules, such as those in game 20.2. However, if instead you simply learn to read a conditional statement backwards, writing the contrapositive would only waste time. Further, whenever you "check the rules" for any given question, you essentially see every rule twice (since a conditional and its contrapositive convey the same set of information). This redundancy wastes time, as you check a possible answer against two sets of the initial rules.

These partially defined or undefined games typically give many test takers the most trouble because of their use of and reliance on conditional logic. However, I've found that merely writing the rules exactly as they are and heading straight into the questions is the most time-efficient and accurate way to solve these games. Only spend additional time combining rules that are irresistibly obvious (A --> B, B --> C). And if you combine rules, try to avoid writing them twice (independently and combined).

In sum, I don't believe either Powerscore's approach or Manhattan's approach to game 20.2 deserves special consideration, and instead prefer to write the rules as they are. This allows maximum time for actually solving the questions. Time spent on the stimulus and setup is time away from the questions, which are what net you points. If you construct hypothetical diagrams and logic trees in addition to your main diagram and/or rules, you must be certain that it will not just mitigate time spent on questions, but decrease your overall time spent on the game. I have almost never found this to be the case, except in older games that are solved with key deductions (those games which have not been in fashion on the LSAT in well over a decade).

Hopefully this helps and good luck!


Thanks for this information. I've only started studying for the LSAT and am planning to take it in October, so I guess I must try to get used to not relying so much on writing everything out. I guess it's an insecurity thing to make sure that you have a template that appears that it will be able to solve all questions without much reflection. I've also been practicing on old logic games (from PT 1 to 38) so that may be a problem as well... we'll see. I'm guessing practicing on old games though still gives good practice, but I'll try to ween myself a little bit from the overdiagramming of conditionals advocated by both PS and Manhattan... at least they both suggest being flexible, which means probably for better testers what you are advising.




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