Setup and Rule Diagrams

[Administrator]

Setup and Rule Diagram Explanation

This is an Advanced Linear: Balanced game.

The game scenario establishes that each of five speakers must give a speech at one of two rooms—Gold and Rose. Additionally, each speech takes place at either 1, 2, or 3 PM. While each room must host one speech at 1 PM and one at 2 PM, it is unclear which room hosts the 3 PM speech. This uncertainty is troubling, but we can balance the game by adding a sixth variable (“E” for “Empty”) to designate the 3 PM slot in the room where no speech is being held.

PT73_Game_#2_setup_diagram 1.png

This creates an Advanced Linear diagram, and because there are now six variables for the six positions, this is a Balanced game. With the basic structure in place, let us now turn to the rules.

The first rule establishes that M must be earlier than L, and in the same room as L. Your representation of this sequencing rule should also capture the grouping requirement that M and L be in the same room as each other:

PT73_Game_#2_setup_diagram 2.png

This rule creates the following two Not Laws:

PT73_Game_#2_setup_diagram 3.png

The second rule establishes that neither X or Y can be earlier than Z. The following sequence is impossible:

PT73_Game_#2_setup_diagram 4.png

When handling a rule presented in the negative, immediately examine its positive implication: Z’s speech must be given earlier than X and Y, or else it must be given at the same time as either X or Y (Note that Z cannot be given at the same time as both X and Y, simply because at most two speeches can occur at any given time):

PT73_Game_#2_setup_diagram 5.png

Since Z can be given at the same time as either X or Y, the second rule does not produce Not Laws for X or Y at 1 PM: it is entirely possible that either Z and X, or else Z and Y, are given at 1 PM. However, you should notice that Z cannot be given at 3 PM, because there is only one speech at 3 PM, and it is the last speech in the sequence:

PT73_Game_#2_setup_diagram 6.png

The last rule presents a conditional statement: if L is in the Gold Room, then X and Z must both be in the Rose Room. You can either use “Gold” and “Rose” subscripts, or simply designate each room as “G” or “R”:

PT73_Game_#2_setup_diagram 7.png

Since the necessary condition requires X and Z to be in the same room (the Rose Room), placing them in a horizontal block is more visually powerful. You should immediately make the connection with the previous rule, which ties X and Z into a sequence Z=====X. Of course, if X and Z must both be in the same room, they cannot be given at the same time. So, we can simplify the sequence as Z X:

PT73_Game_#2_setup_diagram 8.png

You should also examine the contrapositive of the third rule: if either X or Z is not in the Rose Room, then L cannot be in the Gold Room. Thankfully, the dual-value system of the rooms allows us to represent the contrapositive as a positive statement: if either X or Z is in the Gold Room, then L must be in the Rose Room. And, since M and L must always be in the same room—with M earlier than L (first rule)—we can add that stipulation to the necessary condition of the contrapositive:

PT73_Game_#2_setup_diagram 9.png

Note that L need not always be in a different room from X and Z! If L were in the Rose Room, for instance, the last rule would have no effect on the placement of X or Z (to conclude otherwise would be a Mistaken Negation). Likewise, if either X or Z were in the Rose Room, it would be possible for L to be in the Rose Room as well. Essentially, L cannot be in the Gold Room with either X or Z, but it can be in the Rose Room with either of them.

Thus, we arrive at the final setup for this game:

PT73_Game_#2_setup_diagram 10.png

PT73_Game_#2_setup_diagram 11.png

Before you proceed to the questions, it is important to recognize that the placement of Z represents a powerful point of restriction. This is because Z limits the placement of two other variables (X and Y), out of the remaining four. Since Z cannot be at 3 PM, it is a good idea to examine the next most restrictive hypothetical—placing Z at 2 PM.

If Z were at 2 PM (regardless of which room it is in), the second rule would prevent X and Y from being at 1 PM. Consequently, one of them would have to be at 2 PM, and the other—at 3 PM. However, this would force the remaining two variables—L and M—to both occupy the 1 PM slot, and in different rooms, which would violate the first rule. Consequently, Z cannot be at 2 PM, and must therefore be at 1 PM:

PT73_Game_#2_setup_diagram 12.png

The inference that Z must be at 1 PM also suggests that L and Z can never be given at the same time:

PT73_Game_#2_setup_diagram 13.png

[Jon Denning]

As a preliminary discussion of the four games on the just-released September 2014 LSAT, the following outlines the game type and some key notes about Game 2. As a general impression I'd say that this was, if not a relatively easy games section, at least an extremely predictable one, which is welcome news after a Circular game in Feb 2014 and a Pattern game in June 2014.

Here are my thoughts on Game 2:

Advanced Linear game--five speakers in two rooms, speaking at either 1, 2, or 3. The game initially appears more uncertain than it actually is, as you aren't told which room holds the speech at 3. However you can balance this by adding a sixth variable "speaker"--I used "O"--and showing that one of the 3 PM speeches is given by that variable. So it becomes a 6 into 6, balanced setup.

The key inference here is that if Z must be equal to or ahead of both X and Y, then Z must give a speech at 1 PM: Z cannot take the remaining 3 PM spot (no room after), nor can Z be at 2 because placing X and Y at 2 and 3 and filling those times means M and L (the only people left) are at 1, and that can't happen as they must be in the same room (rule 1). So Z is always at 1, and then the game is pretty easy. This also answers question 13, the rule substitution question!

Weigh in with any comments or questions below!

Jon

[Morgan O'Donnell]

Thank you for your analysis, Jon!

Morgan O'Donnell
PowerScore Test Prep

[yourfavoriteamber]

Hi Jon. I set this up vertically, with the two rooms as the base. What is the best set up for this type of game?

[James Finch]

Hi Amber,

I'm not Jon, but I'll see if I can help. I would actually set it up with R and G as my two rows and 1-2-3 as my columns, with one template with G having the 3 pm spot and the other template with R having it, like this:

R: _ _
G: _ _ _
1 2 3

R: _ _ _
G: _ _
1 2 3

I find this setup to better represent the linear nature of the game, without messing up the visual representation of the two groups.

[yourfavoriteamber]

Thanks James. I had set it up with the rooms as the base and missed a couple Qs that way. I see now how the times make a better base.

[beccaf]

Hello! Would you not recommend making templates for this game? I didn't use them when I took the practice test and made a couple mistakes in answering questions. But when I blind reviewed it untimed I made templates just to see if they'd be helpful, and found it much easier to answer all the questions. I know they took a bit of time for this game, but then the questions were answered much faster and correctly. I basically did them around whether or not L was in Gold Room or Rose Room. Thank you!

[Rachael Wilkenfeld]

Hi Becca,

Great question. For me, there's too much uncertainty to template this. Even once we place Z, we still could have x and y in any of the other spaces. We still won't know which group has 3 and which has 2, which leads to even more uncertainty. For me to draw out templates, I want to see a very very restricted game.

Hope that helps!
Rachael

[angelsfan0055]

I had a question about setup, too. I did this untimed and got 5/6 with what I believe to have been a careless mistake on the Substitution.

The way I set up was to put

_ _ and then a G under it with a 1 Pm and 2 PM and then _ _ and then an R under it, with 1 and 2 PM under it and then a 3 PM in the middle. This setup worked, albeit it may have taken me longer to answer some of the questions, and I didn't catch the inference that Z has to be first.

Is this still an appropriate setup for this type of game? It reminded of the October 2013 game 3, with the movie theaters and screens. Am I getting this pattern correct or have I just been doing so many logic games these past few days my brain is going crazy

[Adam Tyson]

As long as it made sense to you and was clear and understandable as you went through the questions, angelsfan0055, then it was a perfectly acceptable way to do it! We may have a preferred method, but that doesn't mean our way is "right" and other ways are "wrong." You have to do what works for you, and it sounds like this did.

In the future, though, you may want to give more consideration to the linear aspects that can create a good base, as another similar game might benefit from capturing that a little more visually. Just food for thought.