LSAT scores are estimates of a test taker’s actual proficiency in the skills tested. LSAT scores are not an indication of a test taker’s capacity to learn or to build additional proficiency.
LSAT scores are reported to law schools along with a score band because the estimate of proficiency provided by a given LSAT score is not perfect. The score band indicates a range of scores, including scores slightly higher and slightly lower than the score received, because a test taker’s actual proficiency in the skills tested on the LSAT may be slightly higher or slightly lower than that reflected by the score received on an officially administered LSAT.
The value used to determine the score range is based on a psychometric statistic called the standard error of measurement (SEM). The SEM provides an estimate of the average deviation that is present in test scores because of the imperfect nature of tests.
In other words, even though an individual score received on an officially administered LSAT is an estimate of a test taker’s actual proficiency in the skills tested, it is unlikely that the test taker’s actual proficiency, if theoretically measured perfectly, is more than a few points higher or lower than the score received.