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In this study, two estimation methods for one missing data in unreplicated 2k factorial experiments are proposed. The first method is minimizing sum squared the highest order interaction and the second one is based on the change proportion. From the comparison of 3 measurement criteria: the absolute percentage relative error of the estimate, sum squared and estimates of factorial effects, by using 22, 23 and 24 factorial experiments, it can be concluded that the change proportion method gives a better estimate than the method of minimizing sum squared the highest order interaction.
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