Time Needed : 15 minutes

In this tutorial, you are going to learn the process of how to create a custom bidding algorithm, assign a valid script and then test your entire build.

1. Login to your DV360 account. Navigate to the “Partner” (little house icon), then expand the “Resources” menu and click on “Custom Bidding”.

   1.1 The “Custom Bidding” panel is on the right side and all your algorithms will be stored there. You can click on “New Algorithm” to create your first one.

2. Once the “New Algorithm” window opens, then you will have to specify a “Name” and select the “Advertisers” this algorithm will be assigned to. Then click “Create”.

   It is important to mention that there is a limit of 10 algorithms per advertiser, therefore only select the advertiser that will be using the script. If you run out of algorithm slots, you can always archive old ones.

3. When you create the algorithm shell, you will be directed back to the main “Custom Bidding” panel. You will have to click on the algorithm again.

   Here is why! You will see a red warning circle next to your algorithm. This is simply because there is no script assigned that provides the logic for the custom bidding.

4. In the top tab select “Script” (will explore the rest of the tabs later) and click on “New Script”.

   Before you begin your scrip writing process, it is worth mentioning that Custom Bidding is NOT compatible with the following formats: Gmail, YouTube, Twitter, Audio, Tag Guaranteed, or Programmatic Guaranteed inventory.

5. This is the most important part! With some basic knowledge of Python, you can write any type script and assign different weights to user actions (ad click, conversion, cart revenue and etc.). Furthermore, the scripts can be validated and tested in real-time!

   5.1 When you are writing your script, you can always click on the “Check Syntax” button. If you have no errors in your script, you will see a green checkmark with a message “Syntax verified”. If there are errors, the validator will share more information with you and point you to the row(s) where the mistake has occurred.
   
   5.2 You have to select the advertiser which you want to test your script against.
   
   5.3 This is the sampling method you need to choose in order to test the logic of your script against historical data. there are a few options you can choose:
   
   – All impressions: This will include all impressions for the advertiser and provide you with an overall expected distribution of impression values.
   – Only impressions with clicks: If your script involves clicks then you would want to use this option.
   – Only impressions with conversions: Most common one if you are using weighted conversions or GA goals. This includes all conversion events in your advertiser, and will be based off the default attribution model.
   
   5.4 Click on “Test Script” and you will get a performance summary for a sample of 10,000 impressions obtained in the last 30 days.
   
   5.5 Once you “Create” the script, you might not see it appear immediately in the “Script” tab/list. However, that is perfectly normal, it can take up to 20min for the script to load, then all warnings will disappear.
   

6. You can navigate to the “Summary” tab, where you are going to find all the important diagnostics about your Custom Bidding algorithm.

   6.1 Once again, you would have to “Choose an Advertiser…” to see the relevant metrics against it:
   
   – AVG impression value by cost: When assigned to a campaign, the Custom Bidding algorithm optimizes for ROAS as defined by your Custom Impression Value (the actions in the script) divided by the Cost (your media spend). The higher this value is the better, as this means you are getting more of the actions described in the scrip at a lower cost.
   – Number of impressions with values >0: These are the impressions that scored positively against your script. For example, if you have given a specific weigh to a conversion in that script and you have 50 conversions from that type, then you will have 50 positively scored impressions. Therefore, make sure you have enough volume of positively scored impressions are Google has two fairly strict data requirements.
   -> At least 1,000 positively-scored impressions for an Advertise.
   -> At least 50 positively-scored impressions for an individual Line Item (LI)
   
   6.2 All custom bidding algorithms require prior scored impressions (within the advertiser) to train a model, more specifically 30 days window of data. Therefore, you may have to wait a bit before using your algorithm as a bidding strategy. When ready, the “Status” will switch from Training to Ready.