•Arandomized blocked design (RBD)is a plan for collecting data inwhich each of k treatments is measured once in each of b blocks.•Ablockis factor that may affect the measured result but it is not ofprimary interest•The order of the treatments within the blocks is randomized (theorder of the treatment-block combination is not randomizedEXAMPLEAn experiment was performed to determine the effect of four differentchemicals on thestrengthof a fabric. Five fabric samples were selected,and a RBD was run by testing each chemical type once in random orderon each fabric sample.a) What is the experimentalfactor? What are thetreatmentsb) What is theblock??COMPLETE RANDOMIZED BLOCKED DESIGN
