Stochastic Block 

In addition to the automatic blocking of invoices due to variances or the amount, invoices can also be blocked at random using the stochastic blocking procedure. A stochastic block is used to make sample checks. If the stochastic block is active and you post an invoice that is not subject to any other blocking reason, it can be randomly selected for blocking.

In the Customizing system of Invoice Verification you can make the following settings:

If the threshold value is $1000 and the percentage 50%, the degree of probability that an invoice over $1000 will be blocked is 50%, whereas the degree of probability for an invoice over $500 is 25%. If you want the degree of probability to be the same for all the invoices, you must set the threshold value to zero.

Stochastic blocking is not carried out on item level, but for the whole invoice. If a stochastic block is set when you post the invoice, the system automatically sets an R in the field Payment block on the vendor item screen; the individual items do not contain a blocking indicator.