Here, in India we have a large number of centralised exams. Everyone in school has to go through two centralised 'board exams' one in Class X and one at the end of school in Class XII.
Most universities also have centralized assessment. Thus even though classes are held seperately in a number of colleges, the year-end exam is a centralized exam conducted by the University
I feel that it is essential to bring out the problems in centralized assessment. There is one primary advantage and that is that a centralized exams serves as a leveller with everyone being graded on the same scale. There are a few disadvantages and I feel they far outweigh the advantages.
1)Centralized exams, since they have to be for everybody, are necessarily set at the level of the lowest common denominator. Thus they are essentially simplistic in nature, and this has the very serious effect of preventing discrimination between an average student and a good student. With a simplistic exam, an average or even below average student can do as well as a brilliant student if not better. This is something which is also present in the SAT , for example.
2)Centralised exams, involve a lot of answer scripts, and this means a lot of people to check these papers(This is not a problem with the SAT which is completely objective). This ensures that the quality of correction goes down drastically. Thus, in a centralised exam, it would be suicidal to adopt a new approach to solving a problem. Chances are that the examiner would cut it out because he just has so many scripts to correct that he cannot afford to spend too much time.
I feel, thus, that the system of centralized exams discourages originality and is extremely counterproductive. I'm sure such systems exist in other countries also, and I would like people to put down their views below this.