The year is divisible by four. The — mber months are here. It can only mean one thing — a US election is on the horizon.

The quadrennial battle pits two of America’s largest digital marketing teams against one another. To the losers, a hefty Facebook invoice to wipe away the tears of defeat with. To the winners, a chance for that guy who appeared in all their ads to run the country for four years.

If the past decade is anything to go by, the digital war that’s waged over the election is going to be fiercer than ever in the run-up to November. …

The digital advertising market is now worth some $110 billion per year. Despite the market’s ever-growing size, 60% of all digital spend still goes to just two players, Facebook and Google.

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Both of these players dominate their respective spaces. Facebook controls 83% of social media ad spend, whereas Google accounts for over 80% of search spend, and 96% of streaming video spend.

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What’s notable about these platforms’ dominance is that they haven’t come organically. …

In marketing, what is a CPA?

This sounds like one of the most introductory questions to marketing that you could ask, but I think very few people fully grasp what a CPA represents. As easy as the answer to this question might seem, understanding the answer at a fundamental level can teach us a lot about how to run efficient marketing.

So, what is a CPA?

CPA typically stands for cost per action. You might see it used as an abbreviation for something else, like cost per acquisition, but for the purpose of this article we’re going to treat all these variants as interchangeable.

A CPA is a measure of how much it costs you to drive a particular action. This action could be a purchase on an ecommerce site, a registration to your newsletter, or whatever action you care about in your marketing. …

For a game that seemingly has nothing to do with advertising, Battleships can teach us a whole lot.

You’ve probably played Battleships. You know, the game where two players place a set of battleships on a grid, and take it in turns to sink one another’s ships by guessing their location.

For a game that ostensibly has nothing to do with ads or marketing, it can teach us a hell of a lot about both of them. To see why, let’s consider a simplified game of Battleships.

Battleships 8x8 grid

Hunting Battleships

Let’s say you’re playing a game of Battleships with a 10x10 grid, and (to keep things simple) we’ll say that each player has one ship that’s 5 grid squares long. …

If you’ve run digital advertising campaigns for a number of years, you’ll likely have noticed that ad prices have a tendency to increase over time.

Answering why this happens is fairly straightforward. As advertisers see good results on a platform, they increase their volumes. New advertisers join in, increasing competition. As most platforms sell ad space via an auction mechanic, the increase in advertiser demand pushes up prices.

Though the idea that ad prices increase over time is hardly surprising, I’ve never seen any attempts to forecast exactly how much they’ll increase in a given period. …

The rapid rise in Covid-19 cases throughout the Western world isn’t just changing how we behave, but also what we search for.

With the rapid rise in Covid-19 cases throughout the Western world, it’s no surprise that many of us are turning to Google for information. We’re not just researching the virus itself; Covid-19 is changing how we search for travel, entertainment, and financial information.

To understand how the rise in cases is affecting our search behaviour, I used the Google Trends API to pull data on a range of different search trends which either positively or negatively correlate with the rise in searches for coronavirus. Below are some of the most interesting graphs that I found.


It’s no surprise that the increase in Covid-19 cases globally has had a large impact on our attitudes to travel, and subsequently what we’re searching for. With cases rising in popular holiday destinations, and the ever-growing threat of border closures, more and more people are asking how to cancel their flight…

When I’m giving interviews for a numerical marketing role, there’s one question I really like to ask:

Say you’re marketing a product and your margin per conversion is $10. What cost per conversion should you aim for?

This is a fairly fundamental question when it comes to marketing, and it’s one that we all implicitly answer when we run marketing, whether we like it or not. It also seems like a very simple question, but answering it in full can teach us a great deal about how to run marketing effectively.

So, what cost per conversion should you aim for?

To simplify things a little, I’m going to assume that the lifetime value per customer is the same as the margin per conversion. This is effectively saying that each customer can convert on the product once and once only. This assumption is the norm for a large number of verticals; for example in finance, where customers only ever take out a specific brand’s financial products like a credit card or insurance once in their life. …

You might have seen the news that came out in the middle of January, about Google’s latest update to how ads appear on search results. Or, quite possibly, you might not have. You might not have even noticed that anything changed with search results.

The reason you might not have noticed anything is that Google’s latest change has been to significantly blur the border between paid and organic search results. Whereas previously Google showed that results had been paid for by including a visible green ad symbol:

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Google’s latest update contains simply a black ‘Ad’ text in the top left:

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In the name of making ads less distinguishable, Google have done two things here.

Firstly, they’ve changed the colour of the ad icon, and removed the border that once ran around it. …

Referral schemes. We all know what they are, we’ve all seen them before. “Refer a friend and get $20 off your next order”.

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Sites that have referral schemes tend to all work in the same way. If you’re a customer of that site, you can generate a referral link. You share this with your friends, your family, or whoever else, and if they sign up to the service using your referral link, you get an incentive.

As hard as it is to turn down what is basically free money, very few of us can actually be bothered to go through the hassle of referring friends to the services we use. …

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When you’re launching a new marketing campaign there’s always one question on your mind: what sort of results am I likely to see from this campaign?

If you’ve found yourself in this situation before, you’ve likely used one of the many online forecasting tools out there, or perhaps attempted to build your own in a spreadsheet.

These approaches are great for getting some quick estimates, but they all suffer from the same problem; they’re rigid and inflexible. …


Mack Grenfell

Advertiser, triathlete, and (ex) crypto-trader —

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