Tag Archives: accuracy

Moving Forward with Canadian Census Data

By Naomi Bloch


Chloropleth maps of National Household Survey global non-response data at the dissemination-area level courtesy Scott Bell. Global non-response rates > 50% resulted in suppression of data for that spatial unit. All maps are classified using a quantile classification scheme.


As we move forward (and backward) with the 2016 return of Canada’s long-form census, questions remain for everyone who uses Statistics Canada’s key socio-economic data. Researchers, local government agencies, community organizations, and industry will still need to use data collected via the 2011 National Household Survey and understand how to reconcile that information with long-form census data.

Concerns regarding the reliability of NHS data stem from the lower response rates that resulted from the non-mandatory nature of the 2011 survey. The overall response rate for the survey decreased from 94 percent in 2006 to 69 percent in 2011. Media attention has centred on the fact that Statistics Canada chose not to release survey data for 25 percent of all census subdivisions because response rates for those spatial units were too low. A key question is whether the regions for which we have no reliable data share certain socio-economic characteristics — and if so, how this might impact service provision.

Geothink co-applicant researcher Scott Bell, a professor of Geography and Planning at University of Saskatchewan, has been studying and mapping the spatial patterns of the National Household Survey’s global non-response rates. His work examines various geographic levels, and considers response rate patterns relative to several socio-economic variables. Bell found that across the 15 cities he studied, there are many commonalities between areas where response rates are similar.

In this video interview, Bell discusses his research and its implications.

For more from Scott Bell, see also: The Long-term Impacts of the Short-Lived National Household Survey

If you have thoughts or questions about this video interview, get in touch with Naomi Bloch, Geothink’s digital journalist, at naomi.bloch2@gmail.com.

Geothink Video Interview 3: Our Experts Take on Crowdsourcing

Screen Shot 2016-02-24 at 8.34.20 PMBy Drew Bush

We’re excited to bring you our long-awaited video interview that features Geothink’s experts discussing issues of authenticity and accuracy with crowdsourced data.  Data collected through crowdsourcing methods increasingly has replaced traditional forms of data collection.

This video features Geothink Head Renee Sieber, associate professor in McGill University’s Department of Geography and School of Environment; Daren Brabham, assistant professor in the University of Southern California Annenberg School of Journalistm and Communication; Scott Bell, a professor of Geography and Planning at University of Saskatchewan; And, Claus Rinner,a professor and chair of Ryerson University’s Department of Geography and Environmental Studies.

We hope you enjoy this video as much as we enjoyed making it. Afterwards, leave us a comment and tell us what you think about this important area of debate concerning crowdsourced data.

You can also learn more about crowdsourcing by reading our post on this central topic to our 2015 Summer Institute, listening to these lectures from the Summer Institute, or listening to our experts talk about the topic over lunch last June. 

If you have thoughts or questions about this video, get in touch with Drew Bush, Geothink’s digital journalist, at drew.bush@mail.mcgill.ca.