Guide to Attribution Modelling in Google Ads (Google Adwords)

In the context of Google Ads (formerly Google Adwords), attribution modelling is the process of understanding the role of various keywords, ad groups and campaigns in:

  • Initiating conversion actions.
  • Assisting conversion actions
  • Completing conversion actions. 

Attribution modelling is a very broad topic.

This article talks only about understanding and using attribution modelling in the context of Google Ads.

To understand the very basics of attribution modelling and how it works in Google Analytics, check out this article: Beginners Guide to Google Analytics Attribution Modelling

If you have not already read this article then I would highly recommend you to read it.

It is a good starter guide to understand the various aspects of attribution modelling and can help you greatly in understanding the present article.

Say Good Bye to ‘Last ad click keywords’ optimization

The advent of attribution modelling has fundamentally changed the way we look at the data for good.

Up to now we have been managing PPC campaigns by bidding on ‘last ad click keywords’ (keywords which completed the sales).

This has to change because it is sub-optimal way of optimizing a campaign.

To get optimum results, you also need to invest in keywords which initiated or assisted in sales.

Different keywords (first ad click keywords, middle ad click keywords and last ad click keywords) work together to create a sale.

Yet we remain focus only on the last click keywords.

Not good.

It is quite common for users to refine their search queries (on search engines like google.com) to get the product they are looking for.

And it is also quite common for users to return to a website via a branded keyword (as it is easy to remember) before making a purchase.

Since by default, Google Analytics attributes conversions to the last non-direct clicks, branded keywords end up getting tons of undue credit for sales.

Consequently branded keywords campaigns seem to perform so well in PPC.

But these campaigns are still not producing optimum results because our whole optimization efforts are directed towards last click keywords and we now know, that different keywords work together to create a sale.

If you keep adding more of one unit of production to a productive process while keeping all others units constant, you will at some point produce lower per unit returns.

This is known as the law of diminishing returns.

So in the case of PPC, if you keep optimizing for last click keywords (in our case branded keywords) while ignoring first and middle clicks keywords (collectively known as assist keywords) you will at some point produce lower per unit returns.

What that means, your cost per acquisition at some point will start rising and your profit on sales will start declining.

Then the only way, to remain within your CPA targets is by tweaking (add, pause, delete, change bids) last click keywords.

But this is sub-optimal way of optimizing a PPC campaign, as you are optimizing only the bottom part of the conversion funnel.

So what is the solution?

In order to strengthen your PPC campaigns, you also need to bid on keywords and search queries that initiated and assisted conversions (conversion actions).

In this way you can stay away from the point of diminishing returns and remain within your CPA targets much longer.

How to find keywords and search queries that initiated and assisted conversions via Google Analytics

Identify keywords and search queries in your Google Analytics multi-channel funnel reports that are:

  1. High performing conversion initiators (i.e. the top keywords/search queries which initiated conversions)
  2. High performing conversion assisters  (i.e. the top keywords/search queries which assisted conversions).

Follow the steps below:

Step-1: Navigate to ‘Assisted Conversions Report’ (‘Conversions’ > ‘Multi Channel Funnels’) in your main Google Analytics view.

Step-2: From the ‘Conversions’ drop down menu, deselect all conversion types except ‘ecommerce transaction’:

select-conversion-type

Step-3: Click on the ‘Google Ads’ button:

Step-4: Click on ‘Assisting Interactions Analysis’ tab in the ‘Explorer’ window:

Step-5: Click on ‘Google Ads Keyword’ as primary dimension:

Step-6: Set the date range to the last 3 months:

Step-7: Sort the report by ‘Assisted Conversion Value’ column to find high performing conversions assisting keywords:

Step-8: Compare all the high performing assisting keywords against the keywords you are currently bidding on in your PPC campaigns. Add the keywords which are missing, to your PPC campaigns and then bid on them.

Step-9: Select ‘Search Query’ as primary dimension and then sort the report by ‘Assisted Conversion Value’ column to find high performing conversions assisting search queries:

Step-10: Compare all the high performing assisting search queries against the keywords you are currently bidding on in your PPC campaigns. Add the search queries which are missing (as keywords), to your PPC campaigns and then bid on them.

Step-11: Click on ‘First Interaction Analysis’ tab in the ‘Explorer’ window:

first-interaction-analysis

Step-12: Sort the data by ‘First click Conversion Value’ column to find high performing conversions initiator search queries:

Step-13: Compare all the high performing conversion initiator search queries against the keywords you are currently bidding on in your PPC campaigns. Add the search queries which are missing (as keywords), to your PPC campaigns and then bid on them.

Step-14: Click on ‘Google Ads Keyword’ as primary dimension and then sort the data by ‘First click Conversion Value’ column to find high performing conversions initiator keywords:

Step-15: Compare all the high performing conversion initiator keywords against the keywords you are currently bidding on in your PPC campaigns. Add the keywords which are missing, to your PPC campaigns and then bid on them.

Say Good Bye to ‘last ad click CPA optimization’

The ‘Cost Per Acquisition‘ (also known as ‘CPA’ or ‘Cost per conversion’) that you see in your Google Ads report is not your actual cost per acquisition:

It is the ‘cost per last ad click conversion’.

So if you ignore first and middle click keywords and optimize PPC campaigns on the basis of ‘cost per last ad click’ conversions then you won’t get optimal results and may even lose money.

That is because if a keyword is not completing a sale, it may be initiating a sale or assisting a sale (always remember that).

And if you stop bidding on the keyword because its ‘cost per last click ad conversion’ (the so called CPA reported by Google Ads) is too high or the keyword is not directly completing any conversion then you could lose money.

Similarly the conversions reported by Google Ads are last ad click conversions.

So if you overlook the role of prior keywords in the conversion process then you are missing the big picture.

Introduction to Ad Impressions

Every time your ad is served on Google Ads Networks (Google.com, YouTube, Partner websites and apps), it is counted as ‘Ad Impression’ by Google ads.

It does not matter whether or not your ad was actually viewed by a user.

As long as your ad is served on Google Ads Networks, each serving is counted as one ad impression.

For example, if you ad was served 10 times on Google Ads Networks then the number of impressions counted for the ad would be 10.

Introduction to Measurable & Non-Measurable Ad Impressions

Measurable ad impressions is the number of times your ad could be measured for viewability.

Non-Measurable ad impressions is the number of times your ad could not be measured for viewability.

Ad Impressions = Measurable Ad Impressions + Non-Measurable Ad Impressions

For example, if your ad got 6 measurable impressions and 4 non-measurable impressions then total ad impressions counted for your ad would be: 6 + 4 = 10

Introduction to Viewable & Non-Viewable Ad Impressions

Viewable ad impressions is the number of times your ad was viewable. An ad is viewable when at least 50% of its area is visible for 1 second for Display Network ads or 2 seconds for video ads.

Non-Viewable ad impressions is the number of times your ad was considered non-viewable. An ad is non-viewable when at least 50% of its area is not visible for 1 second for Display Network ads or 2 seconds for video ads.

Measurable Ad Impressions = Vieweable Ad Impressions + Non-Vieweable Ad Impressions

For example, if your ad got 4 vieweable impressions and 2 non-vieweable impressions then total measurable ad impressions counted for your ad would be: 4 + 2 = 6

Summary:

Ad Impressions = Measurable Ad Impressions + Non-Measurable Ad Impressions

Ad Impressions= (Vieweable Ad Impressions + Non-Vieweable Ad Impressions) + Non-Measurable Ad Impressions

Introduction to Ad Click

The event of clicking on an ad is called ad click.

A user can not click on an ad without viewing it.

So an ad click is always followed by one or more ad impressions.

Introduction to Views (or Video Views)

A View (or Video View) is counted everytime a user:

  • watched 30 seconds or less of your video ad.
  • clicked on call to action overlay, cards or companion banner.
  • clicked on the thumbnail for video discovery ads.

Note: Video views do not include video ad impressions or thumbnail impressions for video discovery ads.

Introduction to Ad Engagement

An engagement is counted every time a user:

  • expand a Lightbox ad or a card on a video ad
  • view or click on a Showcase Shopping ad.

Note: Ad engagement generally does not include: ad impressions, ad clicks and video views.

Introduction to Ad interactions

An interaction is the main action associated with an ad format.

Interactions can include: ad clicks, ad engagement or video views.

Example-1:

For ‘Search Campaigns‘, ad interactions include ad clicks.

So if a search campaign has got 100 ad clicks in the last 30 days then Google will report 100 ‘ad interactions’.

Example-2:

For ‘Display Campaigns’, ad interactions can include both ad clicks and ad engagement.

So if a display campaign has got 53 ad clicks and 27 ad engagements in the last 30 days then Google will report 80 ‘ad interactions’.

These 80 interactions is the sum of 53 ad clicks and 27 ad engagements

Example-3:

For ‘Shopping Campaign’, ad interactions can include both ad clicks and ad engagement.

Example-4:

For ‘Video Campaigns’, ad interactions include ‘video views’.

So if a video campaign has got 100 views in the last 30 days then Google will report 100 ‘ad interactions’.

It is important that you understand the concept of ‘Interactions’ as it play a key role in Google Ads Attribution Modelling.

Note(1): Ad interactions do not include ad impressions.

Note(2): An ad impression is different than a video view.

Introduction to Conversion Action

In the context of Google Ads, conversions are called ‘conversion actions’.

A conversion is a website goal or objective.

Following are examples of conversion actions: purchase, lead, signup, viewing of a key page, phone call, app install, store visit etc.

In order to view or create conversion actions in your Google Ads account, click on the ‘Tools’ tab and then click on the ‘Conversions’ link under the ‘Measurement’ section:

 

Types of Conversion Actions

In the context of Google Ads, there are four types of conversion actions.

You can see these different types of conversion actions by clicking on the + button:

 

#1 Website Conversion Actions – the conversion actions recorded on your website (like purchase, leads, sign up, viewing of a key page etc).

#2 App Conversion Actions – the conversion actions recorded on your mobile app (like mobile app installs, in-app action like purchase).

#3 Phone Calls Conversion Actions – Following conversion actions are recorded and reported as phone calls conversion actions by Google Ads:

  1. Calls to a phone number in your ads
  2. Calls to a phone number on your website.
  3. Clicks on a phone number on your mobile website.

#4 Imported Conversion Actions – the conversion actions recorded in the offline world like offline sales or sales over phone.

Categories of Conversion Actions

There are three broad categories of conversions actions (or conversions):

#1 Click through Conversion Action (also known as click through conversion)

#2 View through Conversion Action (also known as view through conversion)

#3 Cross device Conversion Action (also known as cross device conversion)

A ‘click through conversion’ is counted when a user clicks on a Google ad and then complete a conversion on your website / mobile app.

A ‘view through conversion’ is counted when a user completes a conversion on your website / mobile app after viewing (but not interacting) a Google display network ad or Google Video ad.

A ‘Cross device conversion’ is counted when a user interacts with your ad on one device/browser but completes a conversion on another device/browser.

Introduction to Conversion Paths in Google Ads

In the context of Google Ads Attribution Modelling, a conversion path is the sequence of ad interactions with your search network ads and/or shopping ads (on google.com) during the 30 to 90 days period that lead to a conversion action.

Introduction to ‘History Window’ in Google Ads Attribution Modelling

The period of 30 to 90 days prior to conversion action is called the ‘History Window’.

In Google Ads, the history window can have four possible values:

  1. Default (the conversion window you defined while setting up a conversion action)
  2. 30 days
  3. 60 days
  4. 90 days.

The ad clicks and ad impressions which were recorded within the history window are considered for getting credit for a conversion action by Google ads.

The History Window is available in almost all attribution modelling reports in Google Ads.

To see the history window, follow the steps below:

Step-1: Click on the ‘Tools’ tab and then click on the ‘Search Attribution‘ link under the ‘Measurement’ section:

Step-2: Click on the ‘Attribution Modelling’ link in the left hand side navigation. You should then be able to see the ‘History Window’ drop down menu on the right:

Introduction to Conversion Window

Google ads refer ‘History Window’ as ‘Conversion Window’ while setting up conversion actions.

When you are creating or editing conversion actions in Google ads, you get the option to set the conversion window.

Types of Conversion Windows

There are two types of Conversion Window:

#1 Click through Conversion Window (usually refer to as just ‘conversion window’).

#2 View through Conversion Window

Click through conversion window refer to the time period within which, an ad click is considered for getting credit for a conversion action by Google Ads.

View through conversion window refer to the time period within which, an ad impression is considered for getting credit for a conversion action by Google Ads.

To view or edit the click through/view through conversion window, follow the steps below:

Step-1: Click on the ‘Tools’ tab and then click on the ‘Conversions’ link under the ‘Measurement’ section:

Step-2: Click on the name of an existing conversion action:

You should now be able to see conversion window and/or view through conversion conversion window for a particular conversion action:

Step-3: Click on the ‘Edit Settings’ link and then click on the ‘Conversion Window’ row in order to edit the click through conversion window:

You can set the conversion window to any time period that best match with your sales cycle:

In order to determine, how long it takes your customers (who see and clicks your ads) to complete a conversion on your website, segment your reports by “Days to conversion.”

Likewise, you can edit the view through conversion window while creating or editing a conversion action in Google Ads:

Introduction to Attribution Models in Google Ads

An AdWords attribution model is a set of rules that determine how the credit for conversions should be attributed to various keywords, ad groups and campaigns in AdWords.

The attribution model used by Google AdWords is ‘Last AdWords click’.

So the last AdWords click in a conversion path gets all the credit for conversion in Google adwords.

Get the FREE E-Book (52 Pages)

Why you should use Attribution modelling in AdWords?

You should use attribution modelling in AdWords to understand the role of various keywords, ad groups and campaigns in initiating, assisting and completing AdWords conversions.

Through attribution modelling you can understand how users search for your products.

The biggest insight that you can get from attribution modelling is that you can determine the most effective keywords, ad groups and campaigns for investment.

But before I move forward, you need to understand how conversions are counted in Google AdWords and how they could be different from the conversions reported by Google Analytics.

Adwords Conversion paths

Adwords conversion path is the sequence of interactions (ad clicks, ad impressions) that lead up to conversions.

Following is an example of Adwords conversion path:

generic impression > generic click > generic impression > brand click => Conversion

Note: The conversion path is created for each conversion counted by Google AdWords

There are several types of adwords conversion paths:

  1. Click Paths
  2. Transition Click Paths
  3. Impression Paths
  4. Transition Impression Paths

Click Conversion Paths

Click conversion path is a sequence of search ad clicks that lead up to conversions.

types of click paths

A click path can be set at the keyword, search query, ad group and campaign level.

So we can have following different types of click paths:

  1. Keyword Path (Clicks) – sequence of keyword clicks that lead up to conversions.
  2. Query Path (Clicks) – sequence of search query clicks that lead up to conversions.
  3. Ad Group Path (Clicks) – sequence of ad group clicks that lead up to conversions.
  4. Campaign Path (Clicks) – sequence of campaign clicks that lead up to conversions.

Keyword click is an ad click resulted from the keyword you are bidding on.

Search query click in an ad click resulted from the search query used by a person.

Ad group click in an ad click counted for a particular adgroup.

Campaign click in an ad click counted for a particular campaign.

Example of Keyword Path (Clicks): keyword-1  > Keyword-2 > … keyword-n -> CONVERSION

Example of Query Path (Clicks): query-1  > query-2 > … query-n -> CONVERSION

Example of Ad Group Path (Clicks): adgroup-1  > adgroup-2 > … adgroup-n -> CONVERSION

Example of Campaign Path (Clicks): campaign-1  > campaign-2 > … campaign-n -> CONVERSION

Transition Click Conversion Paths

Transition clicks conversion paths don’t show repeated clicks on a conversion path.

That is the only difference between the transition click conversion paths and the regular clicks conversion paths.

For example,

If the regular click conversion path is: keyword-1  > Keyword-1 > keyword-2 > keyword-2 > keyword-2 > keyword 3-> CONVERSION

Then the equivalent transition click conversion path would be:

Keyword-1 > Keyword-2 > keyword-3 -> CONVERSION

transition click paths

A transition click conversion path can also be set at the keyword, search query, ad group and campaign level.

So we can have following different types of transition click paths:

  1. Keyword transition Path (Clicks) – sequence of keyword clicks that lead up to conversions.
  2. Query transition Path (Clicks) – sequence of search query clicks that lead up to conversions.
  3. Ad Group transition Path (Clicks) – sequence of ad group clicks that lead up to conversions.
  4. Campaign transition Path (Clicks) – sequence of campaign clicks that lead up to conversions.

Impression Conversion Paths

Impression conversion path is a sequence of search ad impressions that lead up to conversions.

types of impression paths

An impression path can be set at the keyword, ad group and campaign level.

So we can have following different types of impression paths:

  1. Keyword Path (impressions) – sequence of keyword impressions that lead up to conversions.
  2. Ad Group Path (impressions) – sequence of ad group impressions that lead up to conversions.
  3. Campaign Path (impression) – sequence of campaign impressions that lead up to conversions.

Keyword impression is an ad impression resulted from the keyword you are bidding on.

Ad group impression in an ad impression counted for a particular adgroup.

Campaign impression in an ad impression counted for a particular campaign.

Example of Keyword Path (impressions): keyword-1  > Keyword-2 > … keyword-n -> CONVERSION

Example of Ad Group Path (impressions): adgroup-1  > adgroup-2 > … adgroup-n -> CONVERSION

Example of Campaign Path (impressions): campaign-1  > campaign-2 > … campaign-n -> CONVERSION

Transition Impression Conversion Paths

Transition impressions conversion paths don’t show repeated ad impressions on a conversion path.

That is the only difference between the transition impression conversion paths and the regular impression conversion paths.

For example,

If the regular impression conversion path is: keyword-1  > Keyword-1 > keyword-2 > keyword-2 > keyword-2 > keyword 3-> CONVERSION

Then the equivalent transition impression conversion path would be:

Keyword-1 > Keyword-2 > keyword-3 -> CONVERSION

transition impression paths

A transition impression conversion path can also be set at the keyword, ad group and campaign level.

So we can have following different types of transition impression paths:

  1. Keyword transition Path (impressions) – sequence of keyword impressions that lead up to conversions.
  2. Ad Group transition Path (impressions) – sequence of ad group impressions that lead up to conversions.
  3. Campaign transition Path (impressions) – sequence of campaign impressions that lead up to conversions.

Google AdWords Search Funnels

types of funnels

From the chart above we can conclude that Google Adwords search funnel is a type of single channel paid search funnel.

There can be two types of Google Adwords search funnels:

  1. Google Adwords goal search funnel – it is a sequence of interactions (ad clicks, ad impressions) that lead up to a goal completion.
  2. Google Adwords sales search funnel – it is a sequence of interactions (ad clicks, ad impressions) that lead up to a transaction completion.

Once you have setup conversion tracking in Adwords, the Google Adwords search funnel reports will automatically start populating data overtime.

To access Google Adwords Search Funnel reports, go to Tools > Conversions in your AdWords account and then click on the link ‘search funnels’ on the left hand side:

google adwords search funnels

Search Funnel Metrics used in Google AdWords

Google adwords provide several search funnel metrics in its reports which you must get familiar with.

You can add these metrics in your reports by clicking on Columns > Customize Columns > Search Funnels in your adwords account:

customize columns

search funnels metrics

In order to understand the various search funnels metrics, you first need to get familiar with the following metrics:

Last click – the click on an ad just prior to conversion.

Assist click – any click on an ad other than the last click.

Last impression – ad impression that occurs just prior to the first click on the ad in a conversion path.

Assist impression – any ad impression other than the last impression

Assisted Conversions – total number of adwords interactions (ad clicks, ad impressions) which assisted/helped in completing a conversion.

There are two types of assisted conversions in Google Adwords

  1. Clicks Assisted Conversions
  2. Impressions Assisted conversions

Following are the search funnel metrics reported by Google Adwords:

1. Assist clicks – total number of assist clicks

2. Assist impr. (Assist Impressions) – total number of assist impressions.

3. Click Assisted Conv. (Click Assisted Conversions) – total number of ad clicks which assisted in conversions.

4. Impr. Assisted Conv. (Impressions Assisted conversions) – total number of ad impressions which assisted in conversions.

5. Click assisted Conv. value (Clicks Assisted Conversions value) – total value of all the clicks assisted conversions.

6. Impr. Assisted Conv. value (Impressions Assisted conversion value) – total value of all the impressions assisted conversions.

7. Assist clicks / last clicks – through this ratio metric you can determine whether a keyword generates more assist click or more last clicks.

If the ratio is 1 or near 1 then it means the keyword play equal role in generating assist and last clicks.

If the ratio is greater than 1 then the keyword generates more assist clicks.

If the ratio is less than 1 then the keyword generates more last clicks.

8. Assist impr. / last clicks – through this ratio metric you can determine whether a keyword generates more assist impressions or more last clicks.

If the ratio is 1 or near 1 then it means the keyword play equal role in generating assist impressions and last clicks.

If the ratio is greater than 1 then the keyword generates more assist impressions.

If the ratio is less than 1 then the keyword generates more last clicks.

9. Click-assisted conv. / last click conv – through this ratio metric you can determine whether a keyword generates more click assisted conversions or more last click conversions.

10. Impr. assisted conv. / last click conv  – through this ratio metric you can determine whether a keyword generates more impression assisted conversions or more last click conversions.

 

Related Article: Cross device attribution reports in Google AdWords

Learn about the Google Analytics Usage Trends Tool

The Google Analytics usage trend is a new tool which is used to visualise trends in your Google Analytics data and to perform trend analysis.


Take your knowledge of Web Analytics to the next level. Checkout my web analytics training course.

Take your Analytics knowledge to the next level. Checkout my Best Selling Books on Amazon

Maths and Stats for Web Analytics and Conversion Optimization
This expert guide will teach you how to leverage the knowledge of maths and statistics in order to accurately interpret data and take actions, which can quickly improve the bottom-line of your online business.

Master the Essentials of Email Marketing Analytics
This book focuses solely on the ‘analytics’ that power your email marketing optimization program and will help you dramatically reduce your cost per acquisition and increase marketing ROI by tracking the performance of the various KPIs and metrics used for email marketing.

Attribution Modelling in Google Analytics and Beyond
Attribution modelling is the process of determining the most effective marketing channels for investment. This book has been written to help you implement attribution modelling. It will teach you how to leverage the knowledge of attribution modelling in order to allocate marketing budget and understand buying behaviour.

Himanshu Sharma

Certified web analyst and founder of OptimizeSmart.com

My name is Himanshu Sharma and I help businesses find and fix their Google Analytics and conversion issues. If you have any questions or comments please contact me.

  • Over eleven years' experience in SEO, PPC and web analytics
  • Google Analytics certified
  • Google AdWords certified
  • Nominated for Digital Analytics Association Award for Excellence
  • Bachelors degree in Internet Science
  • Founder of OptimizeSmart.com and EventEducation.com

I am also the author of three books:

error: Alert: Content is protected !!