I am not convinced it must be done by random, but maybe you`re right. But my approach will be to take them in order and record who I called and does this lead to a purchase/contract. The chance to find returning customers is much bigger than convincing a new one if you have some reputation(lets say a 100 000 clients). In the other case when you have less customers and you are trying to find a new ones then calling them randomly has the same value as if it is done in order?
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I am not convinced it must be done by random, but maybe you`re right.
But my approach will be to take them in order and record who I called and does this lead to a purchase/contract. The chance to find returning customers is much bigger than convincing a new one if you have some reputation(lets say a 100 000 clients). In the other case when you have less customers and you are trying to find a new ones then calling them randomly has the same value as if it is done in order?
Parent comment
E.g. you're building a customer database and you want cold callers to ring randomly selected telephone numbers.