Effectiveness of numbers showing the amount of items related to each single filter

I am looking for some evidence concerning the effectiveness of numbers showing the amount of items related to each single filter. I mean the ones you can usually find on the right of each filter, within brackets. Does this piece of info add any value to experience?

As a user a would say it can stimulate or destabilize expectation, due the fact if I am looking for specific item I would be delighted to perceive I will have a great bunch of possibilities or I would start thinking about another seller/supplier in case of scarcity.

Thanks.