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A Grouping Game Overview

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If you’re a student in one of Blueprint’s classes, you’ve probably wrapped up grouping games recently. Let’s recap and talk about distinguishing the different types of grouping games from each other.

In and Out games vs. the rest of ’em

First, what makes an In and Out game different from other grouping games? Let’s contrast two games. Both have a list of eight players. In the first game, you’re asked to choose a panel of four from that list of eight. In the second, you’re asked to split those eight into two teams of four.

The first game is an In and Out game. You’re choosing a panel of four. That’s the “In” group. The remaining four are “Out.” The second game just has two groups of four.

There’s a subtle but important difference between these games. Suppose the first game has a rule that J and K cannot both be selected for the panel. Let’s say that the second game has a rule that J and K can’t be on the same team.

These rules are similar; they both mean that J and K can’t be selected together. “Hate” is how you may know it. But in the first game, while J and K can’t both be “In,” they can both be “Out.” The “Out” group is important to keep track of, but it isn’t really a group. The people who are out aren’t necessarily together–they’re just not on the panel. The consequence is that out of J and K at least one must be “Out”, and they can both be “Out.” They just can’t both be in.

In the second game, each group is a team. If J and K can’t be together, that means that at most one of them can be on any team. Since this game had only two teams, the consequence is that one is on each team.

Stable vs. unstable

Now let’s talk about stable versus unstable grouping. This applies to In and Out games as well as games with multiple groups. Stable means you know the size of the groups. Unstable means you don’t. In stable grouping games, symbolize group size clearly in your diagram. When a group gets close to being full, pay attention. Limits on group size often lead to deductions.

In an unstable grouping game, watch out for rules that affect the sizes of the groups. Those rules are your hint to play the numbers. Unstable grouping games have been much more common in recent years than in most of the history of the modern LSAT, so it’s worth giving the ones you encounter a little extra attention.

Profiling games

There’s one more kind of grouping game, one we call a profiling game. You can think of profiling as a doubly unstable grouping game. In a regular unstable grouping game, the group sizes are unknown but the players are each used exactly once (or at least a fixed number of times). In a profiling game, the group sizes are unknown and the players can go multiple times, too.

On occasion, it might not be readily apparent which list of variables should be the groups and which should be the players. Which one should you use as the “groups” in your set up? You’ll have to take a look at the rules and see which variable set the game places more restrictions on.

For instance, if the game has six Olympians competing in “at least” one of four events, you’ll have to see which variable set the rules constrain more. If the rules place more limitations on how many events each of your Olympians can compete in (say, “Usian competes in twice as many events as Katie” or “Michael and Simone compete in exactly two events together”), then you’ll use the Olympians as the “groups” in your set up. If the rules place more restrictions on how many Olympians can participate in each event (say, “exactly two Olympians compete in curling” or “more Olympians participate in badminton than in table tennis”), then use the events.

Back in the ’90s and ’00s, most profiling games had extensive lists of rules from which it was important to draw many deductions. Lately, many of them have been a bit more open-ended, with many possible outcomes. Some recent profiling games still have important deductions, but it’s a bit more common these days to go into the questions with a relatively blank diagram. On one recent game, a completely blank diagram would even have been a valid solution to the game.

The increased prevalence of unstable grouping and of more open-ended profiling games means that it’s important to make some of the most recently administered LSAT prep tests part of your studies. Blueprint students, you’ll get six of them as your six in-class practice tests. The others are available as extra tests online. Some fairly recent tests will pop up in the lessons and homework, too.