Complete randomization in many industrial and agricultural experiments is frequently impractical due to constraints in time, cost or existence of one or more hard-to-change factors. In these situations, restrictions on randomization lead to split-plot designs (SPD), allowing certain factor levels to be randomly applied to the whole plot units and remaining factor levels randomly to the subplot ...

in this research, effect of vermicompost and plant growth promoting rhizobacteria (pgpr) on physiological traits of lemon balm under drought stress condition was investigated in year 2012 at karaj research institute of forest and rangelands. experiment was conducted as split-split plot in a randomized complete block design with three replications. irrigation (normal: irrigated to field capacity...

For the algorithmic construction of optimal experimental designs, it is important to be able to evaluate small modifications of given designs in terms of the optimality criteria at a low computational cost. This can be achieved by using powerful update formulas for the optimality criteria during the design construction. The derivation of such update formulas for evaluating the impact of changes...

In a recent paper, Monlezun and Blouin (1988) proposed an analysis of covariance for a split plot experiment. They suggest a model consisting of five regression coefficients, one for each of the effects whole-plot treatment means, whole-plot errors, split plot-treatment means, whole-plot and split-plot treatment interactions and the experimental errors. In this paper we critically examine the a...