Modifiers allow users to manipulate bid prices and/or delivery prioritization based on conditions set within the modifier.
A couple rules of thumb for modifiers:
A modifier of “1.0” essentially represents the status quo, which would be the same as not setting a modifier at all.
A modifier greater than 1.0 means an increase in either bid price or delivery (depending on whether it’s a bid or delivery modifier).
A modifier less than 1.0 means a decrease in either bid price or delivery (again, depending on whether it’s a bid or delivery modifier)
When more than one modifier apply, they are stacked – for example, if you have an original bid price of $10.00 and 3 bid modifiers that applied to the request of 1.5, 1.2, and 2.0, the final bid price would be: 10.00 * 1.5 * 1.2 * 2.0 = $36
Bid Modifiers
Bid modifiers allow bid price manipulation, either up or down depending on the factor set (see rules of thumb above).
The “Min Bid Price” and “Max Bid Price” allow users to set limits on how low/high a bid price can be set to, which helps prevent stacked modifiers from going higher or lower than desired.
Delivery Modifiers
Delivery modifiers give users the ability to impact rate of spend depending on the factor(s) and condition(s)
As noted in the rule of thumbs, factors greater than 1.0 increase delivery, while factors less than 1.0 throttle it.
The way this works is the following:
For factors GREATER than 1.0, we multiply the rate of pacing times the factor. So a factor of 3.0 on channel id 12345 would mean that we are 3x less likely to block that request due to pacing than we normally would (assuming there is still budget available).
Similarly, for factors LESS than 1.0, we also multiply the rate of pacing times the factor. For example, a factor of 0.5 on channel id 56789 would mean that we are half as likely to return an ad on that request than we normally would.
Bid Shading
Bid shading allows a user to incrementally decrease the bid price to lower the cost of a demand tag if a budget is already on pace (where “on pace” is defined as >= 90% of goal). It essentially works like another bid modifier that is stacked with any other applicable modifiers when calculating bid price.
More specifically, there is a script that runs once per hour to analyze demand tags that have bid shading enabled.
If a demand tag has bid shading enabled AND is on pace with its budget, its bid shading modifier is lowered by 5% (e.g. from 1.00 to 0.95). This process will continue so long as the demand tag remains properly paced.
If a demand tag has bid shading enabled but is NOT on pace with its budget, its bid shading modifier is increased by 5% (e.g. from 0.95 to 1.00). Bid shading modifiers will never be increased beyond 1.0.
NOTE: Like any other bid modifier, the “Min Bid Price” and “Max Bid Price” set limits on how low or high this modifier can set the final price to.