Copyright © 2000 Northeast Association of Pre-Law Advisors.
All rights reserved. Revised: April 5 , 2001
Eight Common Misconceptions about the LSAT
1. The LSAT works only 16 percent of the time.
There is a great deal of confusion about the meaning of correlation-study results. Correlations are reported on a scale of -1.0 to +1.0, with -1.0 representing a perfect inverse relationship--as one measure goes up the other goes down--and +1.0 representing a perfect positive relationship. The national correlation between LSAT scores and first-year grades tends to be around +0.4. By comparison, the national correlation between undergraduate and law school grades tends to be around +0.25. The correlation for both variables combined is approximately +0.5.
The relationships among LSAT scores, undergraduate grades, and law school grades are all fairly strong, particularly when one considers all of the many and varied personal factors that have an impact on performance in law school--factors that include study habits, determination, work or family obligations, quality of instruction, and many, many others.
The LSAT is used to make admission decisions, not to explain performance variance. These two purposes are very different.
The bottom line is that the LSAT, although limited in its utility, is the single strongest numerical predictor of success in the first year of law school that is available to an admission committee when admission decisions must be made.
2. The LSAT is biased against test takers who cannot afford expensive coaching courses.
LSAC strongly counsels candidates to familiarize themselves with the test format and question types in order to perform at their best. This does not mean that expensive coaching courses are necessary to maximize students' performances. The well-publicized claims of huge score increases from commercial coaching courses typically compare students' unprepared performance to their performance after a course. They do not compare the results a student could achieve through self-study, or other less expensive alternatives, to coached results. Moreover, it is likely that the subset of test takers who take commercial courses differs from the general LSAT population in some as yet unknown ways, thereby making generalizations from their results problematic.
What we do know is this: most LSAT takers do not take a commercial course. In 1996-97, for example, slightly less than one-third of all test takers reported that they had taken a commercial coaching course. This number is consistent with other, independent measures of coaching-course volumes. White test takers are slightly more likely to take a commercial coaching course than black test takers, but both proportions are close to the overall average--35 percent of white candidates reported having taken a commercial course compared to 28 percent of blacks. Moreover, the difference in mean LSAT scores between those who did and those who did not take a commercial course is about 1 point on the 120 - 180 LSAT score scale.
3. If you take the LSAT a second time, you'll boost your score by three points.
On average, candidates who take the test a second time earn scores 2.7 points higher than their first scores. But this number is an average--many test takers achieve greater gains and many test takers actually earn lower scores. For example, among those repeat test takers who earned a 150 on their first LSAT in a recent test year, 628 earned a higher second score, 51 earned a second 150, and 211 earned lower scores. Coincidentally, the average score gain for all test takers (2.7 points) is equal to the standard error of measurement for the LSAT, although these two numbers are not related.
4. LSAT scores and undergraduate grades equal merit.
The LSAT is a helpful tool, but it has limits. LSAC long has urged schools to take a variety of factors into account when making admission decisions, and most schools do. Yet schools that place undue weight on test scores and grades are engaged in misuse of those measures, just as the opponents of affirmative action over rely on test scores and grades to make their legal arguments. The LSAT measures only a limited set of skills that relate to success in law school. The list of other factors that play a role is nearly endless. The challenge for admission policy makers is to identify the qualities that they seek in a student body and then gather information about those qualities from their applicants. There is no entitlement to a seat in law school, regardless of one's test scores and undergraduate grades.
5. There is a meaningful difference between scores that are one or two points apart.
Admission decision makers who face the difficult task of admitting only a fraction of their applicant pools necessarily search through files to find factors that will tip the scales. This is particularly true once the bulk of decisions have been made and the remaining files are those for which there may be no truly distinguishing factors in the files, and no clear right or wrong decision. At this point, it may be tempting to place great significance on LSAT score differences of one or two points. Such reliance is misplaced. LSAC recently began reporting LSAT scores with confidence bands around them--bands that typically range from three points below to three points above the actual score. The bands are meant to be a visual reminder that LSAT scores, like all test scores, have measurement error associated with them, and to encourage score users not to place undue weight on differences that have very little statistical meaning.
6. Some LSAT forms are easier than others.
Each LSAT form is written to a common set of test specifications--specifications that describe both the content of questions and the distribution of questions across the spectrum of difficulty levels. Each scored LSAT question is pre-tested twice--once to gather data about how the item functions on its own, and a second time as part of an intact test section. Data from these pretests allow LSAC to 'equate' each LSAT form. Equating is a statistical process through which the very slight differences in difficulty across LSAT forms can be mitigated, thus allowing direct comparison of results from different tests. Therefore, a December 1998 LSAT score of 150 means the same thing as a 150 from the October 1995 administration, or from any administration since June 1991.
7. The LSAT is graded to a curve, so your score can be influenced by the other test takers with whom you test.
Some candidates mistakenly believe that they will be graded on the LSAT in relation to others who take the test with them. In fact, all LSAT scores are equated back to the original base form, given in June 1991. It is possible, although extremely unlikely, for everyone taking the test on the same day to earn a score of 180. Effectively, an individual test taker's performance is compared to the performance of all test takers since June 1991, except those taking the test at the same time.
8. There is little or no research that supports the use of the LSAT.
Since 1990, LSAC has produced more than 75 research reports touching on the performance of the current test or potential designs for a future LSAT. All of these reports are sent to LSAC-member school libraries and are available free-of-charge from LSAC. Numerous external researchers also have made use of LSAT data, publishing their findings in refereed journals.
The LSAT is the single best numerical predictor of first year performance in law school, that the LSAT is superior to undergraduate grades as a predictor of law school success, and that the two measures when combined, are superior to either one standing alone.