All right!
Excellent!
It is time to continue our adventure in Tableau.
In this lesson, we’ll create our first visualization and it is going to be awesome.
Ready?
Let’s get right into it then!
As you can see the workspace area is empty right now.
We’ve already loaded the GDP data file and we can see that here.
Actually, let’s open the GDP Data Excel file for a second.
I want to make sure you are familiar with its structure.
Here it is.
We have a few blank rows, but Tableau took care of them, then we have a column with country
names, a column indicating that this is GDP data, and several columns with GDP figures
for each of these countries.
And this is the Data sheet we are using right now.
Perfect.
Let’s go back to Tableau.
The way data is organized here is rather interesting.
Our attention should be focused on the ‘dimensions and measures’ part of the screen.
First off, we should notice that Tableau has been very smart and managed to organize our
data – categorical variables are right here under “dimensions”, while numerical data
such as the countries’ actual GDP is under “measures”.
“Dimensions” have been colored in blue, and “measures” are in green.
Ok.
Another important remark we have to make is that some of the fields we see here are in
italics and others aren’t.
The distinction between the two is that Tableau generates certain fields based on the data
it finds.
When Tableau generates its own fields such as the “Measure names” field we see here,
these are fields that are not contained in our original data source, but Tableau deems
that these can be useful and creates them for us.
The same thing is true for “Latitude”, “Longitude”, “Number of records”,
and “Measure values” we see in green under “Measures”.
The rest of the fields written without Italics are the ones we saw in the Excel file we loaded
– “Country name”, “Indicator name”, and the years from 2002 to 2016, where we
have countries’ GDP figures.
Good.
Another important detail I would like to mention is that Tableau adds an icon right next to
each of the fields we have under “Dimensions” and “Measures”.
This is what allows us to understand how Tableau reads the data.
The first field under “Dimensions” is “Country name” and its icon is the globe.
Tableau recognizes that this field is related to actual countries, and it is ready to help
us out when we need to visualize such data.
If I click on the icon, I’ll be able to see that this is a string, and that its geographic
role is of Country/Region, as it should be.
At the same time the tiny “abc” icon of the “Indicator name” field shows us that
this is a text value.
And in fact, when I click on it, I can see that this is a string, but different to what
we have for the “Country name” field, the geographic role of “Indicator name”
is “None”.
That’s because this is purely a text value.
What about the year measures we have below?
Well, these are numerical values, right?
Therefore, it comes as no surprise that when we click on their icon (designating numerical
values), we will see these are numbers.
Ok.
Perfect.
Let’s do the following.
I’ll drag the “Country name” field into the work space area.
And boom  Tableau created a world map that shows us the location of each of the countries
we have in our data source.
It is quite interesting to see that the field we see under Columns and Rows isn’t country
name, but are artificially generated Longitude and Latitude fields.
At first, it may seem strange, but then when you think about it, it is intuitive.
Tableau understands “Country name” is a geographical field.
This is why it will do much more than simply create a row or a column containing a list
of the countries we have in the Excel file.
No, the program is smarter than that.
It reads the countries names, and then creates the two fields “Longitude” and “Latitude”
in order to map each country geographically.
And hence the beautiful map we have here.
Now, if I drag the year2016 in the map, Tableau will update the chart, adding the 2016 GDP
of each country.
We can see that happened, if we hover above each of the dots we have representing the
countries on our map.
See?
The US GDP for 2016 was more than 18 trillion dollars, while Canada’s GDP was around 1.5
trillion dollars.
Ok.
Perfect.
Everything’s good.
Our first visualization in Tableau is almost ready.
One last finishing touch I would like to add is to enlarge the bubbles a bit indicating
how large a country’s GDP is.
To do that, I can work with the newly appeared SUM(2016) pane on the right side of the screen.
I’ll click on its tiny arrow and will select “Edit Sizes”.
The ‘edit sizes’ dialog box allows me to enlarge the bubbles we see in the visualization.
I think this will do.
Let’s click “Apply”, and as you can see the bubbles in the visualization increased.
This makes it a bit easier to compare the GDP of different countries.
The final touch will be to edit the name of this visualization.
I’ll double click here and simply type a title.
Anything is better than “Sheet 1”, that’s why I’ll simply type “GDP per country
comparison”.
And here we are.
That’s our first visualization in Tableau.
And we are just getting started!