GRE Scoring and Percentiles of the Previous GRE test pattern

The quantitative and the verbal ability questions use the computer adaptive method of testing (CAT), with the help of multiple choice questions. This method automatically changes the difficulty of the question depending on whether the candidate is answering correctly or incorrectly. One cannot go back to change the answer once it is confirmed. The first question that appears on the test is an average level question, which half the candidates answer correctly. If this question is answered correctly, then the subsequent questions become difficult. If it is answered wrongly, then the questions become easy. Always remember that the difficult questions fetch you more marks and easier ones score lesser marks. After a spate of wrong answers, if one is answered correctly, then the next question becomes difficult and the level of difficulty thus changes. This approach of administering the exam yields scores that are of similar accuracy while using half the number of items. The GRE is of a fixed length, so it goes on till all the questions are answered. Some tests have a variable length and stop once the candidate’s ability level is zeroed on.

There is a scoring algorithm called the IRT, which is used to score CAT exams, like the GRE. Some non-CAT exams also use this technique to score the exams. The IRT is the Item Response Theory. The difference in CAT exams is that the items are dynamically selected so that the candidate is given only items of appropriate difficulty. There are also psychometric benefits associated with this algorithm. Also, the examinees time is not wasted by answering questions that are either too difficult or too easy for his level of testing. These merits are not available in the non-CAT tests that do not use this algorithm.

However, the GRE subject tests are of a paper and pen format and these also use the IRT for the scoring purposes.

One advantage of this test is that even if a candidate misses a question or two, he can still get an 800. Even if no question is answered, the lowest possible score is a 200.

Scaled score percentiles

The percentiles of the previous GRE test pattern are as follows:

Scaled score	Verbal Reasoning %	Quantitative Reasoning %
800	99	94
780	99	89
760	99	84
740	99	80
720	98	75
700	97	70
680	96	66
660	94	61
640	92	57
620	89	52
600	86	47
580	85	43
560	77	38
540	72	34
520	67	30
500	62	27
480	57	23
460	52	20
440	46	17
420	40	15
400	35	12
380	29	10
360	24	8
340	19	7
320	13	5
300	8	4
280	5	3
260	2	2
240	1	1
220	0	1
200	0	0
mean	456	590
standard deviation	120	150

Analytical Writing score	Writing % Below
6	99
5.5	94
5	84
4.5	67
4	45
3.5	26
3	10
2.5	4
2	1
1.5	0
1	0
0.5	0
mean	3.8
standard deviation	0.9