Some basic questions about CPM ads

I'm in the process right now of researching different ads networks, and although this is super basic, I wanted to make sure I had it right before I proceed with anything.

Am I right in thinking that by putting ads from a few different networks on each page will means that they compete for views and so you get higher rates than you would with just one? Also, say if each network is doing $5 CPM, does that mean if I have an ad from each of 3 networks on each page then I'll get getting $15 CPM collectively, or $0.015 per page view?

Thanks for any and all confirmation/clarification.

Yes, you can increase your revenue by displaying more than one ad per page. You should do a lot of testing in order to find out what works best on your own website. But in order to do this you need to use specific KPIs.

ethical hackers said:

But in order to do this you need to use specific KPIs.

Click to expand...

Can you elaborate a bit on what kinds of KPIs you mean?

KPIs like ad impressions/page, clicks/page, revenue/thousand pages. Only the changes in these indicators will tell you if what you are doing is actually increasing your revenue or not.