Here are the details of eligibility and selection procedure for Bstat from ISI

Eligibility In order to be eligible for admission to this programme, an applicant must have successfully completed 10+2 years of Higher Secondary Education (or its equivalent) with Mathematics and English as subjects.

Selection Procedure All applicants for this programme, except the INMO AWARDEES (see next paragraph), will have to appear for two written tests comprising multiple-choice type and descriptive questions in Mathematics at the 10+2 level. Based on performance in the written tests, a number of candidates will be called for interviews.

The written test is waived for applicants who have been selected as INMO AWARDEES to participate in the International Mathematics Olympiad Training Camp (IMOTC) in the current year or in any previous year, based on their performance in the Indian National Mathematics Olympiad (INMO) conducted by the National Board of Higher Mathematics, Department of Atomic Energy, Government of India. Such candidates will be directly called for interviews. However, like all other candidates, such candidates are also required to apply in the prescribed application form for admission to the programme. Merely holding an INMO Certificate of Merit from Homi Bhaba Centre for Science Education (HBCSE) or clearing any Math Olympiad organised by any other organisation will not suffice for waiver of written tests for selection to the programme.

The final selection of candidates for admission to the programme is based on performance in the two written tests (unless waived) as well as the interviews. The final list of candidates selected for admission is announced after completion of all the interviews.

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