Tableau for Beginners
Open Tableau. The Connect window appears. Select Text file and browse to the location where you saved the Immigrant table. Click Open.
This will bring the data connection window, where we can choose which sheets to use. Since our file only has one spreadsheet, it is automatically loaded into the canvas.
In the lower pane, we can see a preview of the data. Here we can rename columns by clicking the inverted triangle to the right hand side of the column name, as shown here. Change the Population Density 2011 column to PopDens 2011.
Changing Data Types
The blue icon below each column name is the data type that Tableau has assigned to that column. You can change the data type by clicking on the icon and choosing a different type in the drop-down menu. For example, change the PopDens 2011 column to Number(Whole) instead of Decimal. Notice the new format. Change it back to number(Decimal).
Getting Started
Please follow the steps below so you can participate in the hands-on session.
1. Sign up for Tableau Public
Go to https://public.tableau.com/auth/signup and create an account.
2. Download the data
Download the two following tables from the links below. Although the source of each table is from DHS, both tables have been edited for the purposes of training in this session. For the original tables, please visit: http://www.dhs.gov/yearbook-immigration-statistics
- Persons obtaining lawful permanent resident status by state or territory of residence, 2005 to 2014. Source: US Department of Homeland Security, Yearbook of Immigration Statistics.
- Immigrant-orphans adopted by U.S Citizens by sex, age, and state or territory of residence during 2013 and lawful permanent resident status by state years 2004 to 2013. Source: US Department of Homeland Security, Yearbook of Immigration Statistics.
Connecting to Data
Tableau can be used with several data formats including Excel files, text files (.txt or .CSV) and more robust databases such as relational databases and big data files. In our workshop, we will be using Tableau with CSV files.
Please open both files in Excel so you can get familiar with the attributes in each table before we open them in Tableau.
Choosing the Type of Connection
In the top right corner, you can choose to connect your data Live or Extract it. Live connections are best suited for datasets that are constantly changing. If your data does not change often and your goal is to eventually publish your data, then let Tableau import the data into it's fast engine and choose Extract, which is what we will use for our datasets in this session.
If it asks you to save the extracted data to your computer, follow the prompts. If not, you will not see any changes and your data is ready for analysis.
Once you are done, add the second dataset by clicking the Add New Data Source button as shown below.
In the Connect pane, select Text File and add the Permanent Resident table. Click Update Now to see the records. Make sure to Extract the data. Now both your tables are ready for analysis in Tableau. Don't close your window.
Visualizing your Data with Graphics
Now that you have become familiar with your data and have it ready for visualization with Tableau, it is important that you take some time to think about the questions that you are trying to answer with your visualization and the type of variables that you have to work with. Take a look at the chart below to help you choose the best type of visualization. Although Tableau automatically activates what type of charts are available depending on the nature of your data, it is important that you understand the basic principles for each type of graphic.
