Firstly, an aspirant should understand that the both the papers in Civils Preliminary Exam have equal importance with reference to marks i.e. 200 marks. The combined marks are taken to determine what is called as the cut off mark. However, the number of questions in both the papers is different. Also, the aspirant has to understand that there is a penalty for incorrect answers which is called as Negative Marking. 0.33% marks are deducted for every wrong answer (unless the questions are exempted from negative marking).
Why Negative Marking?
While answering the Test Booklets, there is a possibility that a candidate may have no knowledge of the subject but would make a guess and shade the most plausible answer in the multiple choice. When there is no Negative Marking (for example : In the Group-I or Group-II exams ) a candidate gets credit for it but for a wrong answer, there is no deduction of marks ( i.e., negative marking). Since the purpose of the Preliminary Examination is to pick up the competent and serious-minded candidates, it was considered expedient to introduce negative marking for wrong answers.
This would give an advantage to the candidate who has a thorough knowledge of subject and would eliminate candidates, who have merely superficial knowledge and want to score by mere guess work. In other words, introduction of negative marking for wrong answers would screen out the less serious candidates. However, if a candidate leaves a question unanswered, it would be an evidence that he is an honest candidate, who does not claim to know the answer and there should be no negative marking for this.
Go to Part 1 of the article to know more about structure of Preliminary Examination.