# Seminar at SMU Delhi

October 30, 2013 (Wednesday) , 3:30 PM at Webinar
Speaker: Aloke Dey, Indian Statistical Institute, Delhi
Title: Efficiency factors for natural contrasts
Abstract of Talk
With reference to a partially confounded design for a symmetric 3-level factorial experiment, we obtain an explicit expression for the efficiency factors of natural contrasts of the form linear, linear vs linear, linear vs quadratic, etc. This expression involves the harmonic mean of the efficiency factors for orthogonal components or, pencils. It is also shown that such a neat result does not exist for general s-level factorials where s is larger than 3. Nevertheless, the case of such general s is also explored.