Tuesday, July 21, 2009

Logical Reasoning Week - How the LSAT Has Changed

Yesterday we discussed our philosophy and approach to the most misunderstood, yet most important, section of the LSAT. Future posts will include a graph of the most common question types (or task standards, as we call them at Zen), and how to correct mistakes made on the most important of the 22 task standards.

For today, we'll answer if you can use the cheap Official PrepTest books--the only LSAT books Zen of 180 recommends--from the "before" 1998-2002 LSATs and still get appropriate practice on logical reasoning for the newest LSATs from "after" the June 2007 LSAT redesign.

Lots of people worry about whether they have to spring for the brand spanking new, $8-a-pop PrepTests; our analysis of the Zen task standards show that the newest books are not necessary to get accurate scale scores for logical reasoning sections. While analytical reasoning has been made indisputably harder with more hybrid games and reading comprehension stole a question from AR and added comparative passages in 2007, the logical reasoning sections have remained relatively unchanged.


As you can see from the graph, the relative importance of each task strand to the others has remained the same. The only two significant differences are a ~4% increase in evaluating evidence and roughly equivalent decrease in analyzing logical structure. However, these drifts in point distribution are not significant enough to warrant the exclusion of the older LSATs from your study.

The question then becomes: if the task strand distribution is relatively the same, are the older logical reasoning questions similar in difficulty to the current LSATs? This requires more of a qualitative assessment, but our initial reaction is that any change in difficulty is similarly negligible.

However, there are several important points - outside the obvious price advantage - that make the older tests more desirable for self-study over the newer PrepTests.

1) Even if the questions are easier and ramp up in difficulty as some claim, then it provides a natural learning curve for students; starting at the somewhat easier material and working up to the modern level helps build confidence and provides appropriate content for lengthy practice. If you are to incorporate the older PrepTests, ensure you use them at the beginning of your self-study.

2) The question stems in the older LSATs are more varied than in modern LSATs. That is, there are more ways to learn how the LSAT phrases a given task standard; this provides a greater opportunity to develop a personal understanding of which task the LSAT is prompting. While "identify the flaw in logical structure" may work best for one student, "which flaw in reasoning did the author make" may help another student more. After internalizing the different task standards, it is easier to identify them in the more rigidly composed question stems of the current LSATs.

3) The sheer volume of real LSAT questions allows for targeting the logical reasoning section, task strands, or even specific task standards. While it seems inefficient to use a single serving LSAT PrepTest for such focused practice, the
10 Official LSAT PrepTest series provide the flexibility of using the same sections from a series of LSATs to create an intense, all logical reasoning study session.

4) Similar in use to number 3, but overlooked by many test takers, is the fact that the PrepTests are significantly shorter than the actual LSAT; they are missing the experimental section that adds 25% to the length of the test. Taking sections from the older PrepTests and spreading them throughout the modern LSATs
as mock experimentals allows you to accurately simulate test-day length in your regular practice.

Tomorrow, look for the first journal entry from a Zen student as he applies our methods to his self-study, specifically to the logic games; he's one who confused them for logical reasoning at first! Thursday we'll continue our analysis of the modern logical reasoning sections, including advice on how to tackle the most prevalent task standard: evaluating evidence use.