In early 2000 when the test-maker began to introduce e-rater, there was a great controversy on this computer program. People simply don't believe it. Some students even type "I don't want to be graded by a robot" in their responses on test day. Several years later, however, the e-rater proved to a reliable substitute for high-cost human grader.

The e-rater works like a search engine, such as the world-wide used Google. It is comprised of a computer program and a database. The database stores hundreds of sample responses to each essay topic. The computer program scans your essay and then determines its relevancy to the pre-written essays in database. If your essay is similar to the 6.0 essay, then your essay receives 6 point. If similar to 5.0 essays, then it receives 5.0 point and so on. In other word, if you write an essay that is very similar to a high-score essay in test-maker's database, then you will get a high score.

Fooling the e-rater is easy if you are able to identify what it favors and what it does not. In the following passage, we will introduce the most commonly used structures and words/phrases in 6.0 essays.

The E-rater favors transitional words

Ordinal numbers that introduce examples or reasons: first, second, third, first of all, etc.

Transitional words that relate each sentence to other: since, because, therefore, thus, etc.

Mood words that indicate the author's position: fail, ignore, overestimate, underestimate, exaggerate, misrepresent, overlook, etc.

Counter-evidence indicators: actually, despite, admittedly, except, even though, nonetheless, nevertheless, although, however, in spite of, do, does, may, might, etc.

The E-rater doesn't recognize innovation
The computer program doesn't recognize creative writing style, such as "SHIFT_the future". This phrase can not be recognized since it doesn't accord to the standard expression. Rather, you should put it in "shift the future".  (Courtesy: gmatcat.com)