Common Admission Test
Common Admission Test (CAT) is a computer based test held only in India. This test scores a person on the bases of Quantitative Ability, Data Interpretation, Verbal Ability and Logical Reasoning. The Indian Institutes of Management (IIMs) started this exam and use the test for selecting students for their business administration programs. The test is conducted every year by one of the IIM's based on a policy of rotation. In August 2011, it was announced that Indian Institutes of Technology (IITs) and Indian Institute of Science (IISc) would also use the CAT scores, instead of the Joint Management Entrance Test (JMET), to select students for their management programmes from 2012-14 year.
Before 2009, CAT was a paper based test conducted on a single day for all candidates. The pattern, number of questions and duration have seen considerable variations over the years.
On 1 May 2009, it was announced that CAT would be a Computer Based Test starting from CAT 2009. The American firm Prometric has been entrusted with the responsibility of conducting the computer based test. The first computer based CAT was marred by technical snags. The issue was so serious that it prompted the Government of India to seek a report from the convenor. The trouble was diagnosed as 'Conflicer' and 'W32 Nimda', the two viruses that attacked the system display of the test, causing severe slow down.
CAT is conducted by the Indian Institutes of Management as a pre-requisite for admission to various management programmes of IIMs, Indian Institutes of Technology (IITs), Indian Institute of Science (IISc), National Institutes of Technology (NITs), Faculty of Management Studies (FMS) and few other institutions.
CAT is normally conducted every year during a 21 day testing window (estimate but may vary) in the months of October and November. A candidate can appear for CAT only once during the 20-day testing window. The test score is valid for admission to the forthcoming academic year only.
Exam format 
The CAT, like virtually all large-scale exams, utilises multiple forms, or versions, of the test. Hence there are two types of scores involved viz. raw score and scaled score.
The raw score is calculated for each section based on the number of questions one answered correctly, incorrectly, or omitted. Candidates are given +3 points for each correct answer and -1 point for each incorrect answer. There are no points for questions that are not answered. The raw scores are then adjusted, as necessary, through a process called equating. Equated raw scores are then placed on a common scale or metric to ensure appropriate interpretation of the scores. This process is called scaling.
Three scaled scores will be presented for each candidate: an overall scaled score and two separate scaled scores for each section. As the two sections evaluate distinct sets of knowledge and skills, scores do not correlate across... sections. A high score in one section does not guarantee a high score in another section. Percentile rankings are provided for each individual section as well as for the overall exam score.
See also 
- "Selection process". www.catiim.in. Retrieved 10 February 2012.
- "CAT replaces JMET in IIT, IISc". Deccan Chronicle. 27 August 2011. Retrieved 10 February 2012.
- "CAT to go online from this year". Business Line. 1 May 2009. Retrieved 10 February 2012.
- "Snags hit 7,000 candidates at CAT". The Hindu. 1 December 2009. Retrieved 10 February 2012.
- "Govt seeks report from CAT convener on exam disruption". Times of India. 30 November 2009. Retrieved 10 February 2012.
- "IIM-A names two viruses that caused CAT chaos". The Economic Times. 1 December 2009. Retrieved 10 February 2012.
- Non-IIM Institutes, (Indian Institutes of Management Official Website)
- CAT 2011, (Prometric Services)
- Scoring in CAT, (Prometric Services)