This page explains how the GRE computer-adaptive testing (CAT) system adapts to your ability level, and how the scoring system accounts for the adaptive nature of the test.
How the GRE Computer-adaptive System Builds a Customized Test for You
The computer-based GRE interacts with you by continually tailoring the difficulty level of the test to your abilities. How does the CAT accomplish this? The initial questions of each type that are presented to you will be moderate in difficulty. If you respond incorrectly to these initial (moderately difficult) questions, the CAT then presents questions of the same type that are somewhat easier (although not necessarily similar in content). Correct responses, on the other hand, will prompt the CAT to pose questions that are more difficult (although not necessarily similar in content).As a result, questions presented later in a section are more likely than earlier questions to match your ability — that is, to be neither too easy nor too difficult. The CAT does not adjust difficulty level by increasing or decreasing the total number of questions presented. The CAT selects appropriate questions from a large bank of questions, categorized by content and difficulty. Thus, although the overall content (topics covered) and total number of questions is the same for all test takers, each test taker is presented with a distinct set of test questions.
Skipping Questions, Returning to Previous Questions, and Finishing a Section
The CAT does NOT allow you to skip questions. Given the interactive design of the CAT, this makes sense. The computer-adaptive algorithm cannot determine the appropriate difficulty level for the next question without a response (correct or incorrect) to each question presented in sequence. The CAT does NOT allow you to return to any question already presented (and answered). Why? The computer-adaptive algorithm that determines the difficulty of subsequent questions depends on the correctness of prior responses. For example, assume that you answer a particular question incorrectly. The CAT will respond by posing slightly easier questions. Were the CAT to allow you to return to that earlier question and change your response to the correct one, the other questions presented would be easier than they should have been, given your amended response to the earlier questions. In other words, the process by which the CAT builds your score would be undermined.
The CAT does NOT require you to finish each section. The CAT gives you the opportunity to respond to a total of 58 scored questions (28 Quantitative and 30 Verbal). However, the CAT does not require you to finish each section. If your pace is a bit slow and you fail to respond to every question, the CAT will nevertheless tabulate a score, based upon those questions that were presented.
NOTE: At least one response for each test section is required to generate a score report for that section. If you don't confirm a response to at least one question on a given test section, an "NS" (No Score) will appear on your official score report for that section (but scores for the other test sections will still be tabulated and reported).
Do Computer-literate Test Takers have any Advantage on the Computer-adaptive GRE?
In developing the computer-based GRE, ETS has taken every measure to eliminate any advantage a computer-literate test taker might have on the test. Test takers use only the mouse (not the keyboard), so no keyboard commands are involved. The tutorial, practice, and required demonstration of competence prior to the test further ensure a level playing field for all test takers. Despite the efforts of ETS to eliminate any advantage that a computer-literate test taker might have, a test taker who is experienced with a mouse and at ease with computers may in fact be at a ever-so-slight advantage. Also, adept typists will hold an advantage when it comes to composing essay responses using the test's word processor.
