Marin offers a variety of Strategy rules, which allow advertisers to layer additional controls on to the automated bidding system. After bidding has been calculated, a few optional rules are available which impact the final bid pushed to the publisher. We'll explain these rules and what they mean below.
There may be occasions when a bid is constrained by more than one Strategy rule. For example, a calculated bid may be above the Strategy bid cap and may deviate from the current bid by more than the maximum bid change rule configured on the Strategy.
This article will also document the interaction of the Strategy rules in cases like this where multiple rules are applied to a given object's bid calculation in a Matrix of Strategy Rule Interactions.
Definitions And Best Practices For Strategy Rules
It’s important to note that Marin calculates bids algorithmically based on historical data, then applies the optional rules outlined below.
Following are definitions for the various Strategy rules in Marin:
Boost
The Boost feature allows a user to increase the calculated bid by a specified percentage. For example, if the calculated bid based on the Strategy settings is $1.00, a 20% boost would increase the final bid to $1.20. This feature can also be used to decrease the final bid by entering a negative value as a percentage boost.
Note: If boost settings conflict with other Strategy rules, such as maximum bid change, the other rule(s) will be given priority. For example, if a keyword has $1 bid, a 50% boost, and a 25% max bid change, the final bid will be $1.25 because the max bid change is given preference over the 50% boost.
Bid Cap
This is the maximum bid you are willing to push for a biddable object (keyword, ad group, placement, product group). Any time the calculated bid is over this amount, it will be truncated to this value. Even if a Boost is applied, the bid will never exceed this amount. If left unchecked, the default value is the daily campaign budget cap.
Maximum Bid Change
When selected, the application's bidding will only push a bid that is within X% of the current bid. For example:
Current bid: $1.00
Calculated bid: $4.00
Limit changes: 50%
In the above case, Marin would push a bid of $1.50 (150% of $1.00)
We generally recommend leaving this setting at the default of 25% to allow bids to be reactive to changes in performance data, without incurring excessive risk due to unforeseen changes in the auction. There are some specific cases where it is beneficial to move this value away from the default, specifically where advertisers which to drastically increase bids for a promotion. Additionally, when an advertiser’s average bids are very low (less than $0.10) a larger max bid change may be necessary to avoid “stuck” bids. This feature is sometimes referred to as Bid Dampening.
Minimum Bid Change
In order to limit bid updates sent to the publisher, users can choose to only push bids if there is a significant difference between the current bid and newly calculated bid. If the gap between the current bid and newly calculated bid is less than the amount specified in the Minimum Bid Change rule, the new bid will not be pushed to the publisher. By default, a minimum bid change of $0.01 is used, and we recommend keeping this default setting.
For example, if the Minimum Bid Change rule is set to $0.05, then Marin will not push a bid change because the newly calculated bid is within 5 cents of the current bid.
Impression Share Cap
An Impression Share Cap allows you to set an impression share cap on Strategies that are NOT bidding toward an Awareness Target. This means that even Strategies that are targeting a financial goal (CPL, Margin, ROI, ROAS) can have an impression share cap. For example, if you're bidding toward a Margin goal, an impression share cap will prevent the algorithm from increasing bids on keywords that are already sitting above the impression share cap.
"Always Keep Above Bid For First Page / Minimum Bid"
If this option is checked, Marin will ensure that the bid is greater than the first page bid/minimum bid. Use this setting if you have keywords that you always want displayed, regardless of performance. We recommend entering a Never bid above amount if you are selecting Always keep above first page/ Minimum Bid. If selected, keywords will never be bid above the Strategy Never bid above amount.
Note: This feature is limited to Google Search Campaigns. This option does not work with Microsoft Campaigns, Display Campaigns, Shopping Campaigns or Product Listing Ads due to the lack of position data for these ads.
Note: This feature uses the First Page Minimum Bid, which is an estimate provided by Google of the bid required for your ad to appear on the first page. This estimate does not ensure that a higher bid will keep your ad on the first page nor does it mean that a lower bid would lead to your ads appearing below the first page. This number is merely an estimate and we recommend that you treat it as such.
Note: By default, minimum bids are updated during the nightly sync and bidding jobs run at 5pm. This means that there may be a gap between when the minimum bid is updated and when the maximum CPC is raised to match this change. An earlier bidding job can alleviate this, but may impact platform performance. Please speak to your platform representative for advice.
Bid Floor
This is the minimum bid you are willing to push for a keyword. This rule overrides the economical bids calculated by our bidding algorithm and as a result can cause increase in publisher cost. We advise caution when using these settings as Marin Bidding will not be able to bid under-performing keywords below the specified level.
Additional Bidding Rules And Settings
Max CPL
The Maximum CPL Strategy setting -- also known as a Stretch Target -- allows a lower level of efficiency for keywords with calculated bids below the publisher first-page-bid-minimum. This setting only affects keywords on Google (and does not affect Shopping, PLA or Display Network bids).
Campaign Budget Caps
Marin bids will not exceed the Campaign’s Daily Budget. For Shared Budgets, bids will not exceed the Shared Daily Budget. For example, if a keyword using Marin bidding has a $20.00 Max CPC (Search Bid) but the keyword’s Campaign Budget is $10.00, Marin will set the Max CPC to $10.00.
Set To Publisher Min Bid
Triggered when the calculated bid is below the Publisher Min Bid (a penny for Google, 0.05 for Microsoft). This typically happens when we have a statistically significant number of clicks w/ no conversions/revenue. As a result we set the bid to the PMB and pause the keyword (although we can disable pausing).
Tolerance
The Tolerance/Bid Gap flag is triggered when the calculated bid is close to the current bid. By default, this value is set to $0.05 unless specified otherwise.
Matrix Of Strategy Rule Interactions
You can use the following matrix to understand the effects of constraining a bid.
Note: Click the image below to expand the matrix. It will open in a new tab.
If we are pushing to the 'first page bid', stretch takes priority. However, if we are pushing to the 'target margin bid', minimum bid change takes priority.
If current bid is less than bid floor, bid floor wins. Otherwise bid dampening wins (the bid will be dampened towards the bid floor).
Note: For advertisers using the Dynamic Actions feature, additional interactions may apply. See this article for details on interactions with Dynamic Actions.
