Christep, I have to admit that I have never heard of such a procedure anywhere in the world.

If three people are running for the US Senate from the same state (as is currently the case in Conn) you can vote for the one you want but have no way to vote against one of the others.

The same is true in Israel. When we have elections there are a host of parties but you can only vote for one --and can't cast a specific vote against the others.

Are you familiar with any election procedures such as the one you outlined (perhaps where you live in Hong Kong)?