Contents
- What is the affinity index?
- Why calculate the affinity index?
- Formula and example of calculating the affinity index
- Where is the affinity index used?
What is the affinity index?
The affinity index (affinity index, AFF) is an important metric that allows you to assess the degree of correspondence between your target audience and the base audience. This index is expressed as a percentage and shows how many representatives of your target audience are present in the studied group. For example, if the affinity index of the TV show "Good Morning" is 200%, it means that among its viewers, there are twice as many representatives of your target audience compared to other shows or the overall audience of the country.
This index allows marketers to understand how beneficial it is to use certain communication channels to attract the maximum number of target customers. The affinity index also shows how many times the target characteristic (such as interest in a specific product) is higher in the studied group, making it an indispensable tool in a marketer's arsenal.
Why calculate the affinity index?
Let's consider a situation using the example of a retail store marketer. Suppose you placed ads for your products in two different TV shows. The first channel has 1000 viewers, of which 600 make up your target audience. In show #1, 200 people saw the ad, 50 of whom belong to your target audience, while in show #2, 150 people saw the ad, of which 110 were part of your target audience.
Your director does not want to pay for both ads, and you need to choose which one to keep, justifying your choice. This is where the affinity index will become your reliable assistant, allowing you to mathematically justify which advertising platform is more effective.
Formula and example of calculating the affinity index
The formula for calculating the affinity index is as follows:
AFF = (rating for target audience / rating for base audience) * 100%
The rating for the target audience in marketing is known as TRP (target rating point). The rating for the base audience is denoted as GRP (gross rating point) and shows the ratio of people with the desired characteristic to the entire group. For example, if you have 100 subscribers, and 20 of them left comments, then the basic rating of active users will be 20%.
For show #1, the affinity index can be calculated as follows:
- Base audience rating (GRP) = 200/1000 = 0.2
- Target audience rating (TRP) = 50/600 = 0.083
- Affinity index = (0.083 / 0.2) * 100% = 42%
For show #2:
- Base audience rating (GRP) = 150/1000 = 0.15
- Target audience rating (TRP) = 110/600 = 0.183
- Affinity index = (0.183 / 0.15) * 100% = 122%
Show #1 has an index below 100%, making it unsuitable for advertising purposes, while show #2 demonstrates a sufficient level of affinity and can be used as an advertising platform.
Where is the affinity index used?
The affinity index is applied in various aspects of marketing. It is used for:
- Advertising effectiveness analysis: It helps identify which platform is more advantageous for placing ads.
- Marketing research: When launching a new product, the affinity index helps identify social groups most inclined to purchase it.
- Website audience analysis: Services like Yandex.Metrica automatically calculate the affinity index of your website users based on interests, helping to build hypotheses and increase conversion rates.
Thus, the affinity index becomes a valuable tool that helps marketers make informed decisions and effectively utilize advertising budgets.