#concurrence matrix

Block Design, Incidence and Concurrence Matrix

Block Designs Properties

The necessary conditions that the parameters of a BIB design must satisfy are

$bk = vr$, where $r=\frac{bk}{v}$ each treatment has $r$ replications

no treatment appears more than once in any block

all unordered pairs of treatments appear exactly in $\lambda$ blocks (equiconcurrence) where $\lambda=\frac{r(k-1)}{v-1}=\frac{bk(k-1}{v(v-1)}$ is often referred to as the…