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Bid Modifiers are objects that control bid price and allow advertisers to implement a sophisticated bidding strategy on a single line item without the use of a bidding agent. Bid Modifiers exist under Trafficking > Modifiers. Bid Modifiers can be associated with any line item or campaign, and express two things:

1. When to modify bid prices
2. What factor (how much) to modify bid prices by

Bid Modifiers can be used to either increase or decrease bid prices and are applied after targeting.

For example, if an advertiser values iOS users twice as much and Android users less, they can target both types of users in a single line item and still reflect this distinction with a Bid Modifier. The Bid Modifier would set a base bid, with a multiplier factor that would lower the bid for Android and increase the bid for iOS. In this case, the Bid Modifier applies a factor of 2 to the iOS auction, and .7 to the Android auction. Bid Modifiers can be applied on any targetable module in the UI, including, but not limited to device model, geo, user segments, custom lists, and ad size.

Using Bid Modifiers on Beeswax Default (Hexbid) Bidding Strategies

Bid Modifiers can be used with the following Line Item Bidding Strategies:

• Flat CPM
• CPC Goal
• VCR Goal

Using Bid Modifiers with a Custom Bidding Agent

You can use Bid Modifier in conjunction with your custom bidding agent. Beeswax will pass the bid modifier product to your bidding agent, which you can optionally incorporate into your model. The final modifier product is passed through in the field:

 optional float bid_modifier_multipliers_product = 6 [default = 1.0];

The bid modifier will otherwise not be applied to the bid with which your bidding agent responds.