4. Putting It All Together: How the Postal and Census Geographies are Combined

At EA, our data start at the Dissemination Area level, and are modelled to the postal code level.

This modelling is the secret sauce. By taking DA data and modelling it to postal codes, we provide businesses with a more granular picture of the characteristics of their customers (potential or existing) while also maintaining strict privacy protection standards.

We've also seen how postal codes are practical, small, and actionable. Through the lens of EA data, you can get a complete view of customers. 

Building on the geography relationship map you've been looking at on the last page, here's where we connect postal geography to census geography:


Urban vs. Rural Data

Working with urban versus rural data can present some challenges. As we learned in the Canada Post lesson, a DA in an urban setting contains many postal codes. However, in a rural setting, a single postal code can represent multiple communities and, thus, multiple DAs.

Using the Rural Enhanced Postal Code Conversion File opens in new window or the PRIZM Rural Enhanced License opens in new window allows for more accurate geocoding and PRIZM coding of customers in rural postal codes.

Why do I need to collect both postal code and community name to understand my customers better?

Suppose your data has a high concentration of rural customers (postal codes with a zero as the second digit).

The postal code and community name associated with the client record will provide more accurate geocoding and PRIZM assignment, allowing you to get a better picture of your customers!

 

In Practice

How do we manage the difference between the clean urban relationship and the more challenging rural situation?

We recognize a rural Forward Sortation Area (FSA) when the second digit is a zero.

Rural forward sortation areas mapped

Let's focus on L0M - the yellow polygon. The DA boundaries within L0M are outlined in grey—as you can see, there are many of them in this FSA.

Forward sortation area L0M highlighted to share various dissemination areas within

The dots represent L0M rural postal codes.

Postal codes within L0M mapped

Zooming in, we see a large red dot that represents the postal code in the town of Angus. Angus is the largest population center of all the L0M 1B0 postal codes, and as the main community associated with L0M 1B0, it has been designated the Single Link Indicator (SLI). If we do not include a community name with our postal code, all records will be assigned to the SLI in Angus.

The one L0M 1B0 postal code that serves several other communities is shown as smaller red dots on the map. The PRIZM assignment for each of these communities could all be different, so adding the community name allows us to understand them better.

Communities within the L0M forward sortation area mapped

When we overlay the PRIZM assignments for each community that shares the L0M 1B0 postal code, we can see the different lifestyles associated with each. This is why we include the community name for our rural postal codes.

Communities within the L0M forward sortation area mapped showing different prizm segments


Colloquial Geography

It's important to be aware of other geography layers that come up from time to time.

You've probably heard of the Greater Toronto Area (GTA) before, but is it postal or census geography? You might be surprised to learn the GTA isn't a recognized census OR postal geography, so it won't feature in our products – in fact, the definition tends to differ, so it's better to clarify what you mean by GTA and figure out the appropriate geography from there. At EA, we tend to think of it as being made up of 5 Census Divisions: Durham, Halton, Peel, Toronto and York.

Three maps showing different versions of the greater Toronto area

Similarly, be cautious with terms such as uptown, downtown, inner city, central, etc., as these are colloquial geographies that do not fit into the standard levels we use at EA.

Even within the standard geography, be careful of multiple places with similar names. For example – 'Winnipeg' can be identified as the 'Winnipeg CMA' and 'Winnipeg CSD (city)'.

Map of Winnipeg showing difference between CSD and CMA


Elections Canada

We'll make a mention here of Elections Canada, which also has its own geography. While it's not likely you'll come across this often; it's good to know we use it – especially when elections come around, or you want to benefit from our mapping, analytics, and insights regarding election districts.

EA's Rupen Seoni publicized our use of Elections Canada geographies to understand the 2018 elections. Learn more about this on our website, which links to his full CTV articleopens in new window.