Switching Between Optimization by Placement and Domain

What happens if you’re using algorithmic optimization to optimize a campaign by placement and then switch it to optimize by domain (or vice versa)? In either case, the campaign’s bid history is used to create rules for the new setting. If the campaign has not yet met its learn budget or impression threshold, bids continue until that minimum is met, and rules are set then.

If you switch between placement and domain optimization after a campaign has been running long enough to create rules, these rules are reevaluated for the new setting.

The optimization level dropdown on the optimization tab with placement and domain options

From Optimization by Placement to Optimization by Domain

The optimizer has been evaluating placement level data and made rules accordingly before you switch from placements to domains. The next time the optimizer evaluates the data, it looks at domain-level stats to create the next set of rules. If the domain as a whole is performing well, any higher bid prices will now apply to the domain. If a placement within the has been turned OFF, however, that placement remains OFF.

Since it is easier to meet the impression thresholds you’ve set in optimization at the domain level (as you aggregate across all the placements) compared to the placement level, many bid/status changes could take place during that first evaluation after the change to domains.

For example, if you use these optimization settings:

  • Default bid: $4.00
  • Goal: CTR of 0.10%
  • Max bid: $10
  • Optimize: Placement
  • Bid step: $0.10
  • Impression threshold: 1,000

And a domain has three placements:

Placement Impressions Clicks CTR Are there any rules already?
xyz.com > google > 300x250 1,100 0 0.00% Yes - The placement was OFF
xyz.com > google > 728x90 4,000 6 0.15% Yes - the bid was stepped up (new bid: $4.10)
xyz.com > google > 160x600 50 0 0.00% No rule yet.

When you switch to optimization by domain, what happens to xyz.com?

The domain as a whole now has these stats:

Placement Impressions Clicks CTR What rules will it create?
xyz.com 5,150 6 0.12% This domain is meeting the goal, so the $4.10 bid price now applies to the whole domain.

The 300x250 placement remains OFF.

From Optimization by Domain to Optimization by Placement

In this case, rules were created for the domain as a whole, and now the data is now going to be evaluated at the placement level. Any rules that have already been created (bid prices and domains that have been turned OFF) remain. Again, you might expect many changes the next time the optimizer runs.

For example, if a domain has the same settings as above, except that it's optimized by domain:

  • Default bid: $4.00
  • Goal: CTR of 0.10%
  • Max bid: $10
  • Optimize: Domain
  • Bid step: $0.10
  • Impression threshold: 1,000

And saw the same performance:

Placement Impressions Clicks CTR Are there any rules already?
xyz.com 5,150 6 0.12% Yes – the bid was stepped up (new bid: $4.10)

When you switch from domains to placements, the optimizer now looks at placement data:

Placement Impressions Clicks CTR What rules will it create?
xyz.com > google > 300x250 1,100 0 0.00% Turn this placement OFF.
xyz.com > google > 728x90 4,000 6 0.15%
No new rules: the bid remains at $4.10. The next time the optimizer runs, if there are any new clicks it will then step it up to $4.20.
xyz.com > google > 160x600 50 0 0.00%
No new rules: the bid remains at $4.10