• Communications for Statistical Applications and Methods
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• v.7 no.3
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• pp.759-766
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• 2000

In order to design fractional factorial experiments which include some debarred combinations, we should select defining contrasts so that those combinations are to be excluded. Choi(1999) presented a method of selectign defining contrasts to construct orthogonal 3-level fractional factorial experiments which exclude some debarred combinations. In this paper, we extend Choi's method to general p-level fractional factorial experiments to select defining contrasts which cold exclude some debarred combinations.

• Communications for Statistical Applications and Methods
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• v.6 no.3
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• pp.695-706
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• 1999

When fractional factorial experiments contain some infeasible treatment combinations called debarred combinations we should construct experimental designs so that those debarred combinations are to be excluded by selecting defining contrasts appropriately. By applying Franklin(1995)'s procedure for selecting defining contrasts to Cheng and Li(1993)'s method this paper presents a method of selecting defining contrasts to construct orthogonal 3-level fractional factorial experiments which exclude some debarred combinations.

• The Korean Journal of Applied Statistics
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• v.11 no.2
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• pp.303-315
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• 1998

In a factorial experiment, certain combinations of factor levels clay not be ruled out for operational or economical reason. A fractional factorial design that contains such infeasible combinations, called debarred combinations, becomes too unbalanced to estimate the required effects. This thesis presents a method of selecting defining contrasts for constructing regular $3^{n-p}$ fractional factorial design which does not contain a debarred combination. Consequently, the construction of the design is accomplished by choosing the defining contrasts so that one of defining contrasts is compatible with a debarred combination.