Grouping Setup Practice Drill #3

[Dave Killoran]

In the specific example I made above, yes, that is ultimately how it works

The one thing I will say is my example is intentionally very limited to prove a different point. My fear is that someone else reading thinks that in a two-value system that a rule like T1 V1 means they are always a block (they aren't, T could be in 2 and V could be in 1) or that T1 V2 means they are always apart (they aren't, they could both be in 2 together).

As long as that makes sense, all good!

[leslie7]

Hi Dave,

So I got the drill questions right, assuming that T-V were in a block (basically) but I didn't really make that a block in my diagraming.

Reason being is because
T-->V
/V-->/T

but
V ---> maybe T maybe not T
/T --> maybe V maybe not V

does that make sense what I am saying? (I think ive gathered this from the book)

So TV don't really belong in a block is that right? and if thats the case why do we represent it as a block in this drill? or how could we ever represent a conditional that is expressed in this form in a block ?

[leslie7]

sorry to add to this Dave,

but also is there a strategic reason as to why the groups were represented vertically as opposed to horizontally? I initially began a vertical diagram and for some reason I found it better to work with the horizontal one in this case but if there is a strategical reasoning behind the vertical set up I can adjust to do that instead

[Robert Carroll]

leslie,

To your first post, each senator is going to be used exactly once, by the first rule. So while normally a necessary condition of a conditional can be true without the sufficient being true, it wouldn't work here. If V were on a committee but not T, then T is on the other committee. But then that committee has to have V via the conditional. So now V is on two committees, violating the first rule.

To your second post, the choice of diagram orientation here is entirely arbitrary. A horizontal setup wouldn't have made any difference for this particular game. I can give a small reason to prefer a vertical setup for similar games - our explanations usually presume a vertical setup for grouping games unless we get "talked out" of them by the nature of the game! So most explanations you'll see of similar games will be vertical, like this one. It's a really minor point, though!

Robert Carroll