Toronto Theft: A Neighbourhood Investigation

Geovis Project Assignment @RyersonGeo, SA8905, Fall 2019

By: Julia DiMartella-Orsi

Introduction:

ESRI’s creation of the Story Map changed the way we could visualize data. Not only did it allow for a broader audience to interact and create their own maps due to its easy to use design, it also contained many new amazing functions, templates, and themes. Users can personalize their story by adding in their own images, text, videos, and map layers by creating their own free ArcGIS Online account. Popular templates include Map Series, Tour, Journal, and Cascade.

Get started making your own Story Map here: http://storymaps-classicqa.arcgis.com/en/app-list/

Creating Your Story Map:

Once you have selected the template you want to use the choice is up to you. By clicking the “+” symbol you can choose to include text, media sources such as a videos, a new title page, or immersive content such as a web map.

ESRI also designed Story Maps to link to outside content and various social media sites such as Flickr and Unsplash. ‘Link to Content’ is also extremely useful as it allows users to add photos and videos found on the internet directly to their story map by copying and pasting their link.

To add interactive web maps into your story map users can link map layers from their ArcGIS Online account. Layers can be created in ArcGIS Online, but also in ArcMap where layers are exported as a zip file and imported onto your ArcGIS Online base map. Map layers can also be found online using the ‘add layer from the web’ or ‘search for layers’ options.  The layers that appear are based on the type of ArcGIS Online account you have created. Enterprise accounts contain additional layers provided by your organization, however ESRI also has free downloadable layers available for users without an organization.

Users also have the option to make their story maps public by clicking the globe icon, or private for their own personal use by clicking the lock icon. To save your story map select the floppy disk icon. Your saved map will appear under ‘My Content’ in your ArcGIS Online account.

My Story and Creating Web Maps:

Over the last few years, theft in Toronto has been increasing at a rapid rate. According to the Toronto Police Service, Toronto experienced a total of 5430 thefts between 2014-2018. However, these are only those that have been reported and documented by police. In order to analyze the distribution of theft across the city, the Toronto Police created a point dataset that summarized when and where each theft took place. Additional datasets were also created for prominent types of theft such as bicycle and auto theft.

To compare the number and types of theft in each Toronto neighbourhood I decided to create a story map using the Cascade template. This created a scrolling narrative that would allow viewers to observe the data in a clear, unique way. The reason why I chose to use a story map was due to the number of layers I wanted to compare, as well as use the ‘swipe tool’ to easily compare each neighbourhood. Therefore, I created a series of choropleth maps based on the 2014-2018 theft/crime data from the Toronto Police Open Data Portal.

The following steps were used to create each web map used in my Story Map:

Step 1: Download the point data and add the layer into ArcMap.

Step 2: Use the ‘spatial join’ analysis tool and select your neighbourhood boundary file as the target layer and the theft point data as the join feature. Make sure to select ‘join one to one’. This will produce a new layer with a ‘count’ field that counts the number of thefts in each neighbourhood – each neighbourhood is given a count.

Step 3: In order to produce accurate results, you must normalize your data. To do so add a new field into your attribute table (same layer with the count field) titled ‘Area’, and right click to select ‘calculate geometry’. Change the property to ‘area’ and choose the units you wish to use. Click ‘ok’ and the results will populate your new field.

Step 5: Export the layer and save it as a compressed zip folder. Import the data into ArcGIS Online by clicking the “Add” tab.

Step 6: Once you import your layer you are given a variety of styles to choose from. Select the one you like best (ex: choropleth) as well as the field you wish to map – in this case select ‘count’. To normalize ‘count’ select the ‘divided by’ dropdown and choose your ‘Area’ field. Change the colour of your map to your preference by clicking ‘symbols’.

Step 7: Save your layer to and select the tags that relate to your topic. The layer will now appear in ‘My Content’ where it can be added to your Story Map.

Step 8: To compare each layer add both layers you wish to compare to your story map by using the “+” symbol. Once you have done so, choose the transition type (ex: horizontal swipe) you want to use by clicking on the arrow below. The transition will take place as the user scrolls through your story map.

My Story Map titled “Toronto Theft: A Neighbourhood Investigation” can be viewed here:

https://arcg.is/uiemr