Understanding auction insights: Overlap rate & Outranking share

[#1]

Hi,

I don't quite understand how Overlap rate and Outranking share are calculated. According to the AdWords Help:

> Overlap rate is how often another participant's ad received an impression when your ad also received an impression.

> Outranking share is a percentage defined as the number of times your ad ranked higher in the auction than another participant’s ad, plus the number of times your ad showed when theirs did not, divided by the total number of ad auctions you participated in.

For me this means:
Overlap rate = common auctions / all auctions = 1 - (only-me-auctions / all auctions)
Outranking share = (only-me-auctions + outranking-auctions) / all auctions

If it was like this, the Outranking share would always be higher than (1 - Overlap rate). Obviously, this is not the case.

Where did I get things wrong?

[#2]

Hey Andreas,

I don't think there's a way to get the correct numbers from our side as users, because we don't have access to total number of our auctions. There're cases where we participate in the auctions, but we're are not relevant enough and our ad does not show for the user. Also, because Google does not show how everything is calculated, so it's going to be just assumptions (as we know, Google very often does not keep formulas simplified)

But thinking about your formulas, I think that:

Overlap
For me, we need to consider total auctions where our ads actually appear (because the explanation says Impressions) and the number of times our competitor appeared with us. So it would be something like: Overlap = (Number of times competitors appear with me / My total Impressions) *100

Outranking share = (number of auctions I ranked higher + number of times my ad showed when theirs did not) / my total auctions

Hope this helps.

[#3]

Not your total impressions or total auctions, just the common auctions that you are both competitive in.