The LSAT Variable (Experimental) Section
What Test-Takers Will Know and Won't Know About the LSAT Variable/Experimental Section on Test Day
All students taking the LSAT can be sure that one and only one experimental section will be included on the exam ("variable" is LSAC's official term for the experimental section). They'll also know that the experimental section is unscored and will consist of 24-28 multiple-choice questions to be finished in no more than 35 minutes. Finally, students can be sure of the experimental section's content, based on exactly how many Logical Reasoning, Reading Comprehension, and Analytical Reasoning sections there are on a particular LSAT. Because the LSAT includes a minimum of two, one, and one of these sections respectively, any numbers larger than that identify variable section content by default (if there are two Reading Comprehension sections, for instance, one of them has to be experimental).
Here is what test-takers won't know: which one of the sections is experimental. In the example above, even though the student has deduced that there is an experimental Reading Comprehension section, he or she won't have any way of knowing which one it is. LSAC has discontinued its former practice of making the variable section one of the first three parts of the exam, which often made it possible to identify variable content with certainty (for example, if the third and fourth exam sections were both Reading Comprehension, the test-taker would know that the former was experimental). The variable content now occupies any and all positions in the order of multiple-choice sections, and this method of detection is therefore no longer viable.
LSAT Variable/Experimental Section Approaches
We strongly advise all of our LSAT students to treat every section of the exam as if it is being scored. Just as importantly, it is a waste of time and effort to try to figure out the identity of the experimental section. LSAC is aware that some test-takers will try to do this, and they have taken countermeasures in order to maximize the section's developmental value. The purpose of the experimental section is to scrutinize the effectiveness of questions for future versions of the LSAT, and this objective is undermined if the trial questions are easily seen as such.
The LSAT's Variable/Experimental Section Compared to Other Standardized Tests at the Graduate Level
Optimal standardized test development and maximum assessment value cannot be attained without experimentation, and the LSAT is not the only widely used to test to feature mandatory experimental content. The Graduate Record Examination (GRE), for example, also has an unidentified and unscored experimental section that could cover either of the examination's major content areas. The Graduate Management Admission Test (GMAT) does not have any experimental sections, but there are experimental, unscored questions included in both the verbal and quantitative sections. In short, LSAT test-takers are not alone; every student who sits for one or more of these three major graduate-level tests will be required to complete experimental exercises.
How LSAC Uses the Variable Section
LSAC analyzes test-taker answers to experimental questions on a year-by-year basis, considering issues such as how many students answered individual questions correctly, the total number of correct answers on the experimental sections, and the scores of these students on the rest of the examination. By compiling and examining this data, test developers are able give difficulty ratings for each experimental question, which will be factored into LSAT scaled scores once these questions are integrated into the scored portion of the test. Questions that have poor assessment value, as demonstrated by too few or too many correct answers, can be easily discarded. Experimental questions with strong assessment value typically replace older exercises that have been in circulation long enough for LSAC to assume the answers are public knowledge.
The LSAT Variable Section and Test Security
In addition to its role in test development, the LSAT's variable section has value for test security. At LSAT test centers, students who are seated next to each other will always have different experimental sections. If the variable-section patterns of answer choices among these adjacent students closely match, LSAC officials have strong evidence of answer copying. This type of cheating detection also has the advantage of a very low false-positive rate, representing the best of both worlds in the enforcement of academic honesty.