Diagram

[dan]

Here's a diagram setup for this game.

dan

[alex.chasan]

This is a great setup, but one question: do we know for sure that one truck can't serve the same building twice? If repeats are allowed, that seems to complicate things quite a bit . . .

[dan]

Good question, Alex. We are tracking whether a truck serves a particular office building, not how many times it serves an office building. Think of it more as a yes/no situation.

Hope that helps.

dan

[a3friedm]

What indicators did you use to decide to group the office buildings in the trucks rather then the trucks in the office building? After seeing the diagram it makes much more sense to do it the other way, but I saw the rule regarding Y needing only one more spot and thought of it as a grouping opportunity.

[jake.rambeau]

What indicators did you use to decide to group the office buildings in the trucks rather then the trucks in the office building? After seeing the diagram it makes much more sense to do it the other way, but I saw the rule regarding Y needing only one more spot and thought of it as a grouping opportunity.

I am also struggling with understanding how to choose the base. Even after reading the section of the book, and watching the interactive video lesson on the subject. I understand the objective is to "choose the diagram that leads to the most numerical inferences", but what does that even mean, and how are we supposed to know that up front?

[matthew.mainen]

I definitely founding building around the buildings to be the best method. Here is my set up. It's how I went through the set up. The big inference was that F has to appear in z or y and P has to appear in the other one. This tells us that P can only be used once, as F is used twice, and the two can't be used together. The little X's above the F/P are used to denote this.

I crossed out the rules F can't be with P and T and I go together twice because I put them in the diagram, so there is no need to refer back to them. The only rule I needed to refer back to was the I>S.

Likewise, I crossed out the notation for where F must go at the top because it was ultimately placed in the diagram as the F/P's.

There is a game almost identical to this - PT48 Game 3.



http://farm4.staticflickr.com/3695/1072 ... 3629_k.jpg

[ohthatpatrick]

Hey, all.

I agree, you could definitely diagram this game with either FHIPST or XYZ as the base.

Making FHIPST the base makes some rules easier to symbolize directly on the diagram and it makes some deductions easier, but making XYZ the base makes a lot of the game feel like a normal Grouping game with 'friends' (chunks) and 'enemies' (anti-chunks).

In general, I'll make the smaller group the base on a Grouping game. (Most grouping games are either conditional-grouping with 2 groups ... In/Out, or they're 3 groups)

However, this type of game is what I'd call an "Options" game. As the previous poster indicated there are carbon copies of this game in the 40's (more than just the one cited).

They all share these features:
- In the setup, you get 4-6 people/things that all have one or more (or "at least one") of 3-4 options.

You always know which set of letters to call the "options" because the setup always says "one or more" or "at least one of" right before them.

- In the rules, you get rules specifying the quantity of options something has or comparing how many options one thing has vs. another.
Rule 2 - "F has exactly two options"
Rule 3 - "I has more options than S"
Rule 6 - "T has two options in common with I"

- You also always get at least one rule that deals with matching/mis-matching options
Rule 5 - "F and P don't have any options in common"

Because so many of the rules/inferences hinge on the number of options one thing has vs. another, we find that making the people/things the base of the diagram is easier. It allows you to use the open board's notations to clearly see each person/thing's minimum options (the boxed spaces), possible options (the un-boxed spaces) and maximum options (via the crossed out spaces).

It's harder, though not impossible, to manage that same information with the options as the base.

For example in the diagram just posted, we have to write I > S off to the side (and we should really be noting underneath that I must be 3 or 2 and S must be 2 or 1).

But with FHIPST as the base, a rule like that is noted ON the diagram, we put a 2nd box on I's column to indicate its minimum of 2, and we put a slash in the 3rd row of S's column to indicate its maximum of 2.

This version of the diagram keeps information like that ON the diagram, instead of off to the side, so most of us find it preferable and more efficient.

"Options" games are actually pretty rare. It seems like LSAT fell in love with them for a few years, because you see about 5 of them from Test 42-52, but I haven't seen any genuine "Options" games since then.

So generally I think it will be safer to make the threesome the base in any Grouping game. But if you're savvy enough to recognize an "options" game if/when it's thrown at you, you'll probably find the diagram works better with the 5-6 things as the base and the "options" the letters that still need to be filled in.

Hope this helps.