How to audit attribution models in Google Ads

Sign in to your Google Ads Account
In the upper right corner, click ‘Tools and Settings’
Under ‘Measurement’, click ‘Conversions’
Click to open the desired conversion [eg purchase]
Scroll down until you see the “attribution model”
Make a mental note of that because it will be important later

Attribution

Attribution models let you choose how much credit each ad interaction gets for your conversions. Essentially lets you better understand your ads performance.
Eg what campaign brought the sale and/or lead

Attribution allows advertisers to

Reach customers earlier in the purchase cycle
Match your business
Improve your bidding

Available Models

Google Ads has the following attribution models

Last click: Gives all credit for the conversion to the last-clicked ad and corresponding keyword.

First click: Gives all credit for the conversion to the first-clicked ad and corresponding keyword.

Linear: Distributes the credit for the conversion equally across all ad interactions on the path.

Time decay: Gives more credit to ad interactions that happened closer in time to the conversion. Credit is distributed using a 7-day half-life. In other words, an ad interaction 8 days before a conversion gets half as much credit as an ad interaction 1 day before a conversion.

Position-based: Gives 40% of credit to both the first and last ad interactions and corresponding keywords, with the remaining 20% spread out across the other ad interactions on the path.

Data-driven: Distributes credit for the conversion based on your past data for this conversion action. It’s different from the other models, in that it uses your account’s data to calculate the actual contribution of each interaction across the conversion path. The “Data-driven” model is the default attribution model for most conversion actions.

Conversion action

When you open the ‘Conversion action’ you will see the “attribution model”
Here you have the option to alter or set the desired “attribution model”.
Before you do make changes or write up an audit stating that the “attribution model is off” you should take into consideration elements such as touchpoints, time lag, and sales cycle.

Touchpoints are the ad interactions each user has.
Eg 2 interactions with YouTube Ads, 5 interactions with Display Ads, etc

‘Time lag’ is the time needed in order for a visitor to convert
Eg 10.6 days

Attribution window

Inside the Conversion action, you should see the following

Click-through conversion window
Engaged-view conversion window
View-through conversion window

It is best to set each window to max [90 or 30 days]

Compare attribution models

Sign in to your Google Ads Account
In the upper right corner, click ‘Tools and Settings’
Under ‘Measurement’, click ‘Attribution’
On the left, click ‘Model Comparison
Set the ‘Lookback window’ to 90 days
Set the time period to ‘All time’
Select the desired ‘Conversion Action’

Here you have the option to compare all available attribution models against each other.
You also have the option of comparing various ‘Dimensions’ such as

‘Network’
‘Campaign type’
‘Campaign’
‘Ad Group’
‘Keyword’
‘Device’

When comparing attribution models the most important metric [for any given dimension] is the ‘percentage change’ for conversions, and cost/conv.

If you want to know more about Google Ads audits, then visit the following link

Google Ads Audit guide & free [Notion & Google Sheets] template

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