Diagram

[tommyid1]

Greetings,

I just wanted to make sure that I did not do anything wrong with my set-up; I deduced that F can never be prescribed.

I have gone through and checked my work many times. Could some one confirm or refute my deduction?

Thank you in advance

In regards to the title of this post: I am not requesting a diagram, so I did not feel right about calling this a Diagram post. At the same time, I am not asking about any specific question. Thus, I decided to title this post "Q0." If this kind of post is to be titled "Diagram," please let me know and I apologize.

[giladedelman]

You're right! It does turn out the F can't be prescribed.

Now, would you mind explaining how you arrived at that inference? I'm interested to hear!

[tommyid1]

Sure thing.

We know that there must be exactly one dietary regimen prescribed. Thus, we must split 4 treatments among antibiotics and physical therapy. We can't have 4 of any kind of treatment, and antibiotics max out at 2, so we are left with
1 antibiotic, 1 dietary, 3 physical
or
2 antibiotics, 1 dietary, 2 physical.

Now, if we look at the remaining rules and their contrapositives, we see that
1. If F is in, O is in and W is out
2. If O is in, due to the rule that only 1 dietary regimen can be prescribed, M & N are out.
3. If M is out, V is out.
4. If V is out, due to our numerical distributions, the other 2 physical therapy treatments must be in. But there's the kicker: That means W must be in!

Therefore, F can never be prescribed because doing so would be a contradiction of the rules.

[noah]

Here's the diagram that I created for this game - along with some frames, based on discussion in posts below.

PT24, S4, G4 – Treatments for Illness - Manhattan LSAT.pdf

(66.03 KiB) Downloaded 1768 times

It's surprising that there are two elements that cannot be in. Pretty rare! It's also unrealistic that a mortal human would figure out both of those inferences without doing frames.

The signal to frame this game is that there are a lot of numerical rules that limit groups, as well as a lot of conditional rules that connect to those limitations. The game day signal would be a sense of "!$!%^@ what?!" when you diagram it - e.g. a feeling that you're missing something!

[noah]

For some reason, a heated discussion took place in the wrong place, so I'm re-posting it here:

But wait: I'm spotting a [possible] discrepancy with those above frames?:
If G is selected, don't we know from the contrapositive of the 5th constraint (which reads "G cannot be prescribed if both N and U are prescribed") that if G is selected, then U (and N) cannot be selected? If so, then how can those above frames that have both G and U (the 1st and 2nd frames above) be accurate? Isn't it the case that if G is selected, V and W MUST be selected, given that we know that there always has to be at least 2 physical treatments (U,W,V), and U cannot be selected, leaving W and V to be mandatorily selected?

(oh and please know I don't mean any disrespect to Mr. Noah by suggesting this discrepancy...what he's done for so many LSAT students can't be under appreciated.)

which was in response to this:

After doing the set-up for this game I came to the conclusion that "F" cannot be used as a treatment, because it eliminates M,N,V and W and therefore forces all of the antibiotics into the group. Is this correct?

Yeah, it is correct! Great inference.

Also, in my post-game analysis I thought it might be good to have written out possibilities...using the inference that there must be either 2 or 3 of the physical therapies as a basis. i.e. do a "uvw", "uv", "vw" and "uw" scenario. What are your thoughts on this?

Those are smart frames since the dietary elements are so exclusive. I get:
In - Out
A:G H - F
D:M - N O
P:U V - W

A: G H - F
D: ? - ? N
P: U W - V

A: H G - F
D: M - N O
P: V W - U

A: H - F G
D:M - N O
P: U V W -

Now that I've done those, I'll amend the above - those are great frames - I'll have to revise my diagram!

[noah]

And, now that you've waded through that, here's my response!

The contrapositive of N + U --> ~ G, is not G --> ~ N + ~ U, it's G --> ~ N or ~ U (or you could say, G --> ~ (N + U)

The point is, if G is in, you can have one of N or U, but you can't have both (and you could not have both).

Make sense?

BTW, feel free to correct me all you like! I make tons of errors.

[qccgraphix]

Could someone please explain why G and H have to be in through your second possible set-up?

A: G H - F
D: ? - ? N
P: U W - V

Thanks!

[noah]

Could someone please explain why G and H have to be in through your second possible set-up?

A: G H - F
D: ? - ? N
P: U W - V

Thanks!

Sure. It's a numbers issue. I bet you can figure it out if you consider what the ramifications are of V being out, and there being only two Ps. Take a look at my explanations below:


Highlight to read: If V is out, we have 2 Ps (U and W), 1 D (who knows what) and we'll need two As. Since W in forces F out, we'll need to have G and H in.

Make sense?

[qccgraphix]

Great, I figured it out with your numbers hint. Do you have any advice with grouping games in general? They are my Achilles heel and I'm spending upwards of 12 minutes on some games. Do they become more mechanic with practice?

Ordering games are so easy to visualize, which makes it easy for me.

[noah]

Great, I figured it out with your numbers hint. Do you have any advice with grouping games in general? They are my Achilles heel and I'm spending upwards of 12 minutes on some games. Do they become more mechanic with practice?

Ordering games are so easy to visualize, which makes it easy for me.

They definitely get easier with practice! Try re-doing games several times to help your brain "own" the process.

[qccgraphix]

Great, I figured it out with your numbers hint. Do you have any advice with grouping games in general? They are my Achilles heel and I'm spending upwards of 12 minutes on some games. Do they become more mechanic with practice?

Ordering games are so easy to visualize, which makes it easy for me.

They definitely get easier with practice! Try re-doing games several times to help your brain "own" the process.

Will do! Thanks!

[goriano]

And, now that you've waded through that, here's my response!

The contrapositive of N + U --> ~ G, is not G --> ~ N + ~ U, it's G --> ~ N or ~ U (or you could say, G --> ~ (N + U)

The point is, if G is in, you can have one of N or U, but you can't have both (and you could not have both).

Make sense?

BTW, feel free to correct me all you like! I make tons of errors.

Does this also mean that if G is in, you don't NEED to have either N or U, but you could also have none?

[timmydoeslsat]

Yes, if G is in, you can have both of those variables out.

Or always means both unless stated "but not both."

You do however, have those situations where it is obvious you cannot have both without stating such.

For example: you either drink water or you do not drink water

[noah]

Yes, if G is in, you can have both of those variables out.

Or always means both unless stated "but not both."

You do however, have those situations where it is obvious you cannot have both without stating such.

For example: you either drink water or you do not drink water

Bingo

[YLAGUNAS]

Rule #6 states V cannot be prescribed unless both H and M are prescribed. I diagrammed it like this:

~H and ~M --> ~V
( V--> H or M)

Can you tell me if this is wrong? I looked at a youtube ( ) video and the instructor diagrammed it as follows:

H and M--> V
(~V--> ~H OR ~M)

please clarify which is correct, thank you!

[timmydoeslsat]

Rule #6 states V cannot be prescribed unless both H and M are prescribed. I diagrammed it like this:

~H and ~M --> ~V
( V--> H or M)

Can you tell me if this is wrong? I looked at a youtube ( ) video and the instructor diagrammed it as follows:

H and M--> V
(~V--> ~H OR ~M)

please clarify which is correct, thank you!

That rule is diagrammed as:

V ---> H and M

Its contrapositive would be:

~ H or ~M ---> ~V


This is one way of how to read unless statements. What comes after unless is the necessary part. Do not negate it. What comes prior to unless is the sufficient part and you will negate it.

~A unless B and C

A ---> B and C


Sometimes you will have an unless statement that is formed this way.

Unless B happens, A does not happen.

The part immediately following unless is still the necessary condition. The part after that condition is what is being referred to, the idea of A not happening. So this is our sufficient condition and we will negate it. (A negation of a negated A is positive A)

So we would diagram it like this: A ---> B

And, to be clear, when we have a situation like A ---> B and C...

The contrapositive will have ~B or ~C ---> ~A

This is due to the fact that we only need one of those necessary conditions absent to guarantee A's absence. We can have both absent, but we all we have to have is just one absent.

[jkang]

i'm a bit confused. couldn't you make the inference combining rules 3 and 4 ?

A > B
A > C
therefore, B > C.

F > O
F > /W

therefore, O > /W.

i understand after trying to make a working diagram using this rule, i see that it is impossible. i found myself stuck on what should have been an easy acceptability questions (18) because of this inference. is my inference incorrect or is it the application that cancels the inference?

[noah]

i'm a bit confused. couldn't you make the inference combining rules 3 and 4 ?

A > B
A > C
therefore, B > C.

F > O
F > /W

therefore, O > /W.

i understand after trying to make a working diagram using this rule, i see that it is impossible. i found myself stuck on what should have been an easy acceptability questions (18) because of this inference. is my inference incorrect or is it the application that cancels the inference?

Be careful:

~ O --> ~ F
W --> ~ F

We can get contrapositives:

F --> O
F --> ~ W

So, F --> O + ~ W

But we can't say how O and W affect each other based on these statements.

That error is similar this one:

If Frank goes to the party, Ollie will but Wanda won't. Therefore if Ollie goes, Wanda won't. Not true! If Frank does not go, we could have any combination of Ollie and Wanda.

Clear?

[andrewgong01]

Here's the diagram that I created for this game - along with some frames, based on discussion in posts below.

PT24, S4, G4 _ Treatments for Illness - Manhattan LSAT.pdf

It's surprising that there are two elements that cannot be in. Pretty rare! It's also unrealistic that a mortal human would figure out both of those inferences without doing frames.

The signal to frame this game is that there are a lot of numerical rules that limit groups, as well as a lot of conditional rules that connect to those limitations. The game day signal would be a sense of "!$!%^@ what?!" when you diagram it - e.g. a feeling that you're missing something!

I thought for In Out Games we do not frame. In all In Out games we would have a lot of conditional rules too that are tied to the overall scarcity of the in and out groups too. Would you recommend in general in an In Out Game to frame if we have different subcategories for the elements (e.g. antibiotics, therapies ) and that there are limitations to the distribution of the subcategories?

[jwillis]

I thought for In Out Games we do not frame. In all In Out games we would have a lot of conditional rules too that are tied to the overall scarcity of the in and out groups too. Would you recommend in general in an In Out Game to frame if we have different subcategories for the elements (e.g. antibiotics, therapies ) and that there are limitations to the distribution of the subcategories?

In short, yes!

Closed In Out games (sub-categories) can lead to numerical distributions (because rules such as "there must be 2 of this sort of thing" can lead to limited ways the game can play out) and numerical distributions can open up a framing opportunity. Try always probing a bit to see if framing will work when a game has numerical distributions.