hey
looking at some of the placements in my campaigns
i find it hard to understand how some will win 2 bids and spend 1dollar
and others will spend 0.2 and win a thousand bids.
what causes this massive variation. are some placements more valuable then others.
could this be caused by auto bidding
would this same situation happen if i set my bid manually
thanks
You will see a similar situation with every traffic source out there. Affiliates/advertisers run their campaigns and optimize them, they bid more on good placements and block bad placements that nobody wants to buy from. The same goes for targeting, they bid high for the best segments and stay out of the bad ones. The bad, frequently blocked placements will be cheap, those targeted by many, will be mega expensive. Part of this might be actually caused by the auto bidding system, thats true.
Just so you can get an idea about traffic prices, check this : http://blog.hubspot.com/marketing/mo...vzis1vmsil2386
Those are estimates for google adwords, rememember those are CPC prices, so prices per 1 click 
thanks. ill re run the same campaign with manual bidding to see what the difference might be.