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Optimal change over designs under treatment × unit interaction

Cini Varghese, A.R. Rao , V.K. Gupta


In a change over design, a sequence of treatments is applied to an experimental unit and observations are recorded over the periods and hence it is very much possible to observe interaction between treatments and experimental units. A non-additive model with treatment × unit interaction effects is recommended for such situations, as these effects also contribute significantly to the response measured. Considering a nonadditive model, a uniform, balanced and non-circular class of change over designs with a pre-period has been shown as universally optimal for the estimation of direct effects.


residual effects, non-additive, pre-period, circular, uniform, balanced, universal optimality

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