Subgroups within Logic Games Forum

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6lehderjets

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Subgroups within Logic Games

Post by 6lehderjets » Wed Sep 28, 2011 7:59 pm

I seem to be having some trouble with games that have subgroups (i.e. dogs divided into groups based on breeds, students divided based on year, etc.) I think part of my difficulty is with organization and identifying with rules on these specific games. Does anyone that has had similar issues have any advice for these types of games?

Thank you!

bp shinners

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Re: Subgroups within Logic Games

Post by bp shinners » Fri Sep 30, 2011 1:01 pm

If I'm understanding you correctly, I think you're actually having issues with two different types of games - ordering games where we're told an extra piece of information about each Player (four boys and three girls are being picked for a dodgeball team in the following order), and grouping games where we're pulling from subgroups (five scientists from the following subgroups 3 botanists, 3 chemists, and 4 zoologists are being picked for a panel).

In the ordering game with different groups, you want to make a separate tier for that extra characteristic (in my example, one tier for the name of the children, another for their gender). That way, you can track the overall order, but also whether or not a boy/girl was picked fifth.

In the grouping game with subgroups, you want to use the rules to figure out the possible distributions of those subgroups in the selected/In group. For instance, if there's a rule that only 2 chemists can be selected, and another that more zoologists than botanists need to be selected, you would figure out that there must be 2 chemists, 1 botanists, and 2 zoologists. That's a much more well-defined example than you'll see on the test, but hopefully you get the idea. Now, you want to label each of your slots in your In and Out group with those professions, so you have a slot held open for the subgroup that needs to fill it.

Hope this helps! It's a quick description of two advanced concepts, so if you need a more in-depth explanation, just let me know.

6lehderjets

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Re: Subgroups within Logic Games

Post by 6lehderjets » Fri Oct 07, 2011 9:34 pm

bp shinners wrote:If I'm understanding you correctly, I think you're actually having issues with two different types of games - ordering games where we're told an extra piece of information about each Player (four boys and three girls are being picked for a dodgeball team in the following order), and grouping games where we're pulling from subgroups (five scientists from the following subgroups 3 botanists, 3 chemists, and 4 zoologists are being picked for a panel).

In the ordering game with different groups, you want to make a separate tier for that extra characteristic (in my example, one tier for the name of the children, another for their gender). That way, you can track the overall order, but also whether or not a boy/girl was picked fifth.

In the grouping game with subgroups, you want to use the rules to figure out the possible distributions of those subgroups in the selected/In group. For instance, if there's a rule that only 2 chemists can be selected, and another that more zoologists than botanists need to be selected, you would figure out that there must be 2 chemists, 1 botanists, and 2 zoologists. That's a much more well-defined example than you'll see on the test, but hopefully you get the idea. Now, you want to label each of your slots in your In and Out group with those professions, so you have a slot held open for the subgroup that needs to fill it.



Hope this helps! It's a quick description of two advanced concepts, so if you need a more in-depth explanation, just let me know.
Thanks for the reply I haven't been online lately as I took a break after the LSAT. Based on your description it is the latter type of games you described that I am having trouble with. Would you mind expanding on emphasis I made above I have been using PS so I'm not familiar with the In and Out terms. I'm assuming that refers understanding what variables can and cannot go with another but I just wanted to confirm.

bp shinners

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Re: Subgroups within Logic Games

Post by bp shinners » Sat Oct 08, 2011 2:12 pm

Alright, here's a quick and dirty example of what I'm talking about.

Bill Clinton is giving a lecture series throughout the country. It just so happens to coincide with some of the Top 10 party schools (OU, Georgia, Iowa, UCSB, PSU, FSU, UF, WVU, Ole Miss). His travel adviser has broken these schools up into the following groups: SOUTH (Ole Miss, UF, FSU), EAST COAST (PSU, WVU, Georgia), MIDWEST (OU, IOWA), WEST COAST (UCSB) (yes, I realize that these make about as much sense as the NFL division splits - just bear with me). Bill Clinton gets final say on his travel arrangements. He's picking 5 of the 9 to travel to, based on the following conditions:
1) He must visit at least two Southern school (because he knows about those southern girls)
2) He visits exactly one more East Coast school than West Coast school
3) etc...

We're going to set up an IN group to put all the schools that he's visiting, and an OUT group to put all the schools that he's not visiting. However, we don't know any specifics, just info about the subgroups so far.

I know that he's visiting, at the very least, 2 schools from our SOUTH subgroup and 1 school from our EAST COAST subgroup (because we need more than the WEST COAST; this also means that he can't visit more than 2 of those EAST COAST schools, since there's only lonely UCSB on the west coast, so at least one of those schools is OUT).

IN:__ __ __ __ __
OUT: __ __ __ __

That's the basic setup. Now, I'm going to label some of those slots with subgroup labels so I don't forget to 'reserve' them for the rules that I know:

Code: Select all

IN: __   __   __   __   __
    (S) (S)  (EC)
OUT: __    __   __   __
     (EC)
From here, there are other deductions to be made. However, this should give you a basic method for attacking these problems.

6lehderjets

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Re: Subgroups within Logic Games

Post by 6lehderjets » Sun Oct 09, 2011 4:03 pm

Gotcha. This is a little different from PS's approach but I can see how this would be of great help in some games. Thanks.

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