This is an analysis of marks of unqualified candidates in UPSC Mains 2008. The source of data is orkut. I have prepared a graph of average marks of cadidates subject wise. It show the huge bias against science subjects in IAS. The bias could be at three stages :-
1) during question paper preparation
2) during answer sheet evaluation
3) during subject wise scaling of marks
There is also a direct positive correlation between number of students appearing in a particular optional and average marks obatained in that subject that shows some inherent bias in the scaling formula used by UPSC.
Unzip the file in the link provided and use microsoft excel 2007. Will post a more convenient file format at a later stage.