Summary
In this paper, we present a class of fractional factorial designs of the 27 series, which are of resolutionV. Such designs allow the estimation of the general mean, the main effects and the two factors interactions (29 parameters in all for the 27 factorial) assuming that the higher order effects are negligible. For every value ofN (the number of runs) such that 29≦N≦42, we give a resolutionV design that is optimal (with respect to the trace criterion) within the subclass of balanced designs. Also, for convenience of analysis, we present for each design, the covariance matrix of the estimates of the various parameters. As a by product, we establish many interesting combinatorial theorems concerning balanced arrays of strength four (which are generalizations of orthogonal arrays of strength four, and also of balanced incomplete block designs with block sizes not necessarily equal).
Similar content being viewed by others
References
Bose, R. C. and Srivastava, J. N. (1964a). Analysis of irregular factorial fractions,Sankhya, A,26, 117–144.
Bose, R. C. and Srivastava, J. N. (1964b). Multidimensional partially balanced designs and their analysis, with applications to partially balanced factorial fractions,Sankhya, A,26, 145–168.
Chopra, D. V. (1968). Investigations on the construction and existence of balanced fractional factorial designs of 2m series, Ph.D. Thesis, University of Nebraska.
Kiefer, J. C. (1959). Optimum experimental designs,Jour. Roy. Stat. Soc., B,21, 273–319.
Srivastava, J. N. (1971). Some general existence conditions for balanced arrays of strengtht and 2 symbols,Jour. Comb. Th., A,13, 198–206.
Srivastava, J. N. (1970). Optimal balanced 2m fractional factorial designs,S. N. Roy Memorial Volume, University of North Carolina and Indian Statistical Institute, 227–241.
Srivastava, J. N. and Chopra, D. V. (1971a). On the characteristic roots of the information matrix of 2m balanced factorial designs of resolutionV, with applications,Ann. Math. Statist.,42, 722–734.
Srivastava, J. N. and Chopra, D. V. (1971b). Balanced optimal 2m fractional factorial designs of resolutionV, M=4, 5, 6,Technometrics,13, 257–269.
Author information
Authors and Affiliations
About this article
Cite this article
Chopra, D.V., Srivastava, J.N. Optimal balanced 27 fractional factorial designs of resolutionV, withN≦42. Ann Inst Stat Math 25, 587–604 (1973). https://doi.org/10.1007/BF02479401
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF02479401