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Conversion Attribution

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Digital Marketing - Study Notes:

Attribution modelling

Attribution modeling involves understanding where a channel fits or where a clean keyword fits in the conversion journey.

  • Last click: The default model is last click. So these are keywords that get 100% of the credit for the conversion because they were the last click before the conversion. Other models include things like first click. So the first click in the conversion journey gets 100% of the credit.
  • First click: 100% of the credit is given to the keyword/campaign that initiated the customer journey to conversion.
  • Position-based: The majority of the credit is given to the first and last clicks, with the remaining credit distributed to the keywords in the middle of the path to conversion.
  • Linear: All clicks in the path to conversion are given equal credit.
  • Time decay: Higher credit is given to keywords and campaigns the closer they are to conversion.
  • Data-driven attribution: Google uses historical data, search signals, AI and other factors to apply different levels of credit to keywords and campaigns in the path to purchase to help clarify how each touch point contributes to a conversion in a more scientific and metric based way.

Model comparison

What we do in Google Ads is in the top, in the attribution section of the main menu in the top, we can use our model comparison tool to see what our cost per conversion looks like when we change the different conversion models.

Suppose we’ve created a bunch of awareness campaigns. We can’t use last click conversion for these campaigns because they’re not the keywords that people use to buy our product. They’re the keywords that people use to enter the funnel to do the research and awareness.

So what we might use for those campaigns is the first interaction or first click model, or we might use position-based. Then with our closing campaigns, the campaigns that we have in the bottom of the funnel, we might use the last click campaigns, so the last interaction campaigns and the last interaction model for those particular campaigns.

The last non-direct click might be for our comparison issues. Last Google Ads click is something to test, but it may not fit within your structure. Linear is always good to look at but it’s rarely a good attribution model to apply to your campaign because it gives mixed results, likewise with time decay.

And then when there’s enough data in your account, you’re able to use the data-driven attribution model, which is Google’s artificial intelligence built machine learning model that looks at historical data, keyword interaction, and a whole load of other indicators to understand what percentage of credit each keyword campaign and ad group might get for the activity that you’re driving. So that is currently online and currently available, but not rolled out to everything just until you get the correct amount of data within your campaign itself.

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Cathal Melinn

Cathal Melinn is a well-known digital marketing director, commercial analyst, and ecommerce specialist with over 15 years’ experience.

Cathal is a respected international conference speaker, course lecturer, and digital trainer. He specialises in driving complete understanding from students across a number of digital marketing disciplines including: paid and organic search (PPC and SEO), analytics, strategy and planning, social media, reporting, and optimisition.  Cathal works with digital professionals in over 80 countries and teaches at all levels of experience from beginner to advanced.

Alongside his training and course work, Cathal runs his own digital marketing agency and is considered an analytics and revenue generating guru - at enterprise level. He has extensive local and international experience working with top B2B and B2C brands across multiple industries.

Over his career, Cathal has worked client-Side, in digital marketing agencies and media owners with brands including HSBC, Amazon, Apple, Red Bull, Dell, Vodafone, Compare the Market, Aer Lingus, and Expedia.

He can be reached on LinkedIn here.

Data protection regulations affect almost all aspects of digital marketing. Therefore, DMI has produced a short course on GDPR for all of our students. If you wish to learn more about GDPR, you can do so here:

DMI Short Course: GDPR

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