We have made a number of changes and enhancements to the way we are producing our statistics in this release. Our aim is to continue to increase the amount of statistics that we make available to the community through this website.
Significant quality improvements have been made to the way the geographic distribution of crime is presented in our statistics. For some areas, that has resulted in small changes from the figures published in previous years and the historical data included in this release. As we have re-based all our data, all offence data we publish in this, and future statistical releases, will have more accurate geographic location.
Additionally, in response to user requests, we have made changes to how offences occurring at justice and immigration institutional facilities (prisons, youth justice facilities and immigration detention centres) are represented in the data. Previously, we have included the crime statistics relating to these facilities in the LGA in which they were located. From this release onwards, we are separating the crime statistics relating to these justice and immigration detention facilities from the LGAs in which they reside. The rationale for this, is that these facilities sit apart from the rest of the community, and crime occurring in these facilities is not a true reflection of crime occurring within the community. These statistics are now represented in their own category in LGA outputs, called ‘Justice institutions and immigration facilities ’, so that they can be clearly identified.
Greater use of interactive elements
CSA has implemented a data visualisation in our offence output for the first time from this release. This presentation – similar to our existing Crime by Location tool – allows visitors to the website to interact more with the offence dataset than is possible when publishing static excel spreadsheets. We have put together a handy guide to advise on how this visualisation works. It is also possible for the custom views of data created by selecting different data within the visualisation to be exported in spreadsheet format for easy use. See the PDF ‘Offences Data Visualisation Guide for Use’ for more information on how to use the visualisation, available in the Recorded offences. We have also included some helpful hints, such as how to calculate percentage change.
Additional breakdowns for key crimes against the person and property
In response to the many requests we have for family violence breakdowns of crimes against the person and for information about whether certain property crimes and residential or non-residential, we have now built these additional categories in to our Offences visualisation for easier use. This increases the amount of data freely available on the website and removes the need to make a custom request from the CSA for these data.
More granular data
The offences visualisation also contains more detailed information than the CSA has released before. In addition to the improvements detailed above, it is now possible to generate even more detailed breakdowns of crime for LGAs and suburbs, as well as search for specific offences and codes at the most granular level recorded by Victoria Police.
We have also made improvements to the 24 month trend test used to indicate whether or not an offence category has significantly increased, decreased or remained stable over the past two years. The CSA uses Kendall’s Rank Order Correlation to perform this test, and from this release onwards has also added threshold criteria, to determine whether it is appropriate to perform significant testing on a specific category of criminal offences. One of two criteria must now be met: there must not be less than 30 offences recorded in any month and the category must contribute more than 0.1% of all recorded offences. This means offence categories and LGAs will be excluded from significance testing if they fail both of those threshold criteria.
For more information about all these changes, see the Explanatory Notes.