There is an old marketing saying which goes something like this: half the money spent on advertising is wasted – the problem is no one knows which half.

I would never buy anything from an unknown phone caller, so the advertising money spent on telemarketing is definitely wasted on me. I think many others feel the same.

Cold calling in Hong Kong is so out of control, it makes you contemplate murder

To find out just how many are in this group, instead of the proposed statutory “do-not-call” register, an opt-out system, the Hong Kong government should set up opt-in system, a “do-call” register, where people can sign up to receive telemarketing calls.