Table 2.

An example generalized decision table $\mathcal{D}=\left(U,,,A,\cup ,\left\{d\right\}\right)$ for case–control study of autism, where $A$ is a set of three genes $\left\{g_1,,,g_2,,,g_3\right\}$ and a risk factor $\left\{r,f\right\}$, and $U$ is a set of objects that belong to equivalence classes ${[q}_1],\cdots ,[q_8]$. The values in $U$ are discrete gene expression levels “low”, “medium” or “high” and a presence of undefined risk factor “yes” or “no”. For simplicity we omit the brackets in the notation in the table. For the equivalence classes $q_4$ and $q_5$ both diagnoses are written since some of the indiscernible objects belong to the boundary region

Equivalence class	$g_1$	$g_2$	$g_3$	$\mathit{rf}$	$\mathit{diagnosis}$
$q_1$	Low	Low	Medium	Yes	Autism
$q_2$	Medium	Medium	Medium	Yes	Autism
$q_3$	Medium	Low	Medium	Yes	Autism
$q_4$	Medium	Low	High	No	Autism or control
$q_5$	Low	Low	High	No	Autism or control
$q_6$	Low	High	Medium	No	Control
$q_7$	Medium	High	Medium	Yes	Control
$q_8$	Medium	High	High	No	Control