1. Aggregation
In this video and following exercises, we will be looking at aggregation.
2. What is aggregation?
Aggregation means gathering and summarizing data points for analytics.
This can mean different things depending on your use case. For example, it could be adding up sales, getting a user's average age, counting distinct customers, or finding the product with the maximum sales.
3. Aggregating measures
Most commonly, we aggregate measures and Tableau automatically does so with sum.
As you have probably seen in past exercises, there are several options for aggregations from average, count, percentile, to variance.
4. Aggregating dimensions
Not as much of a common use-case as measures, we can also aggregate dimensions. Tableau doesn't automatically aggregate dimensions, however the platform provides four options: minimum, maximum, count, and distinct count.
If you choose to aggregate on a dimension, it creates a temporary measure like this.
5. Dataset
In the next few exercises, we'll be using another Gapminder dataset with four metrics: Child mortality rate per 1000 births, GDP per Capita, C02 Emissions per Person in tonnes, and Life expectancy.
These are popular indicators of economic development and there are often relationships between these metrics.
There are also two others columns that segment Life Expectancy and GDP per Capita into categories of ranges. We will see why it is useful to have some measures in a dimension form.
6. Let's practice!
Now let's try it on Tableau!