You must be wondering which ad forms are the most effective and bring the biggest profits. Though the basic method is testing and individual approach (after all, each website is different), on the basis of our observations we can state that there are some aspects that make some ad forms more effective than the others.

• Wide forms seem to be clicked more often
• Standard rectangular forms tend to be the most effective: 338×280 px, 300×250px and vertical 160×600 px.
• Rectangular forms, big banners and skyscrapers can generate higher earnings because Adkontekst Exclusive can display in those forms (here you can find the minimum ad form sizes for Adkontekst Exclusive).

Thanks to our flexible approach to ad form creation you can adjust the size and layout of ad forms to practically all websites. Apart from the standard ad forms you can create your own in the following sizes:

• width from 740 to 1600 px
• height from 86 to 416 px

You’re welcome to test it!

You are already familiar with one of the most important indicators in the statistics - eCPM - and with the basic information on channels. Now it’s time for practice which means A/B testing.

A/B testing is a method that enables us to compare the effectiveness of two ad forms. Thanks to it we can test layout effectiveness and the effectiveness of our thematic category choice.

It is best to use an example to picture the concept of A/B testing. Imagine that you want to test the effectiveness of ad forms with and without visible URL. Below you can see ad forms the effectiveness of which we are going to test:

We could paste the first ad for a week and than the other one for a week and check the effectiveness of those forms. However, this method would have some disadvantages, e.g. we have to remember to change the form at a certain time. Ad choice can differ, we have no guarantee that we would have enough impressions within the testing period. That is why we are going to use A/B testing.

How to start A/B testing

In the beginning we create 2 channels. Remember to name them in a way that won’t let you confuse them in the future. In our example I have created the following channels:

• URL
• No URL

Then we create ad forms for each channel. I have pasted them above.

Now, when we have the right ads we have to find a way to display them alternatingly. If our site has 5000 impressions we want each ad to show up 2500 times.

To get this result let’s use a simple code. You can find it here:

<script type=”text/javascript”>
var random_number = Math.random();
if (random_number < .5){
//1st ad code
} else {
//2nd ad code
}
</script>

You can find a different code based on PHP on the Webmaster Tutorials website. They work the same so you can use both.

How to analyse A/B testing statistics

After a sufficient period (remember that the bigger the sample - number of impressions - the better) we can compare the statistics of both channels using advanced reports. And to compare the data we will use our knowledge on eCPM - I send you back to the source.

 In the previous entry we wrote about the most important indicators to be found in the Publisher Panel. Here we will focus more attention on the most important of them - eCPM - which can be used to compare the effectiveness of chosen ad forms.

eCPM is:

eCPM=(total earnings/number of impression)x1000

How to use eCPM to optimise ad forms on your websites? Above all we have to create two channels. For example give them the same categories, the same ad forms, but different colour palettes. Thanks to such action we will be able to compare the influence of different colours to the click frequency.

Let’s assume that we have created 2 channels. The first one has green titles, the second has red titles. All other parameters are identical for both channels. After creating the ad forms we place them on our website and wait for their statistics (the more data, the better).

After a weeks time we find out that the green titled ad was displayed 12 901 times and earned PLN 5 and the red titled ad was displayed 19 627 times and earned PLN 14. eCPM for the green titled form is PLN 0.39 and for the red titled form PLN 0.71. What does it mean?

It means that if the green titled ad had 1000 impressions it would have earned PLN 0.39 and if the red titled ad had 1000 impressions it would have earned PLN 0.71. This is a very important piece of information. It is very probable that if we change title colours our earnings will grow.

Feel invited to test the effectiveness of different ad forms. Remember that the colour palette is one of the changeable parameters. Different ad form versions with e.g. changed categories, URL visibility or sizes are also worth testing.