PORTAL USER GUIDE
A Diversity Index measures the degree of specialisation or alternatively the degree of diversity across attributes within a spatial unit. This allows spatial units to be compared as to the mix of the characteristics being measured.
The diversity index for a particular region can range from 0 to 1, where a score approaching 0 indicates an increasing degree of diversity and a score approaching 1 indicates an increasing degree of specialisation. Determination of whether a region has a high or low diversity index is done by comparing the diversity index scores across all regions.
For this worked example, we will calculate the diversity of dwelling structures for SA2s across Melbourne.
To do this:
- Select Greater Melbourne GCCSA as your area
- Select the dataset ABS – Data by Region – Family & Community (SA2) 2011-2016 with the variables:
- SA2 Code
- SA2 Name 2016
- Year (with Filter Value: 2016)
- Dwelling Structure Flat Or Apartment No.
- Dwelling Structure Other Dwelling No.
- Dwelling Structure Semi-Detached, Row Or Terrace House, Townhouse Etc. No.
- Dwelling Structure Separate House No.
- SA2 Code
Once you have added this dataset to your cart, open the Diversity Index tool (Tools → Indices → Diversity Index) and enter the following parameters:
- Dataset Input: the dataset that contains the variables you would like to include. Select ABS – Data by Region – Family & Community (SA2) 2011-2016.
- Key Column: the column containing the unique identifier for each area. Select SA2 Code.
- Variables: the variables you would like to be included in the calculation of the index. We will use the four dwelling counts from the ABS dataset.
- Select Dwelling Structure Flat Or Apartment No.
- Select Dwelling Structure Other Dwelling No.
- Select Dwelling Structure Semi-Detached, Row Or Terrace House, Townhouse Etc. No.
- Select Dwelling Structure Separate House No.
The input parameters are summarised in the image below, once complete click Run Tool.
Once the tool has run, click the Display button on the pop-up dialogue box that appears. This will open a window with the outputs of your Diversity Index tool.
A new column is added to the table indicating the SA2’s diversity index score. Lower values indicate a higher degree of diversity. You will note that there are rows that have a diversity index score of zero or null, these are a result of missing data from one or more of the columns in the input dataset. These can be removed with the Filter by Attribute tool.
To visualise the map, follow the instructions using the Choropleth tool.