Razieh Khodsiani - Department of Computer Science and Statistics‎, ‎Faculty of Mathematics‎, ‎K‎. ‎N‎. ‎Toosi University of Technology‎, ‎Tehran‎, ‎Iran
Akram Fakhari-Esferizi - Department of Mathematical Sciences‎, ‎Isfahan University of Technology‎, ‎Isfahan‎, ‎Iran‎

For the interference models‎, ‎the assumption is often made that the size of the blocks (k) is not greater than the number of treatments (t)‎. ‎Typically‎, ‎it is difficult to specify optimal block designs theoretically or algorithmically when k> t. ‎In this article‎, ‎we focus on a one-sided interference model with compound symmetry correlation for the observations and obtain universally optimal block designs for both cases k≤ t and k>t. ‎We present some methods for constructing these optimal designs for various numbers of treatments and block sizes.

Circular block design, Compound symmetry structure, Interference model, neighbor balanced design, Universal optimality