Montreal 311 Service Requests, an Analysis

In early 2015, Nicolas Kruchten collaborated with a reporter from the Montreal Gazette, Roberto Rocha, to analyze a dataset containing information about 1.4 million service requests received by the City of Montreal from its citizens. The resulting article was entitled "Montreal's 311 records shed light on residents' concerns — to a point" and credits Nicolas at the bottom. The dataset, obtained from the city's Gestion des demandes clients (GDC) system via an Access to Information request and also worked on by Stéphane Guidoin, covered the five years from 2008 to 2012 and contained only the date and a very short description for each request, and in most cases, an address. Notably missing was any indication of resolution time or correspondance with the originating citizen. The service requests were received by the city through its 311 phone line or at service counters throughout the city.

In these pages, you will be able to walk through the process of analyzing the 1.2 million requests which were linked to a specific borough through an interactive pivot table such as the one you see below. As you advance through the steps of the analysis, the table will reconfigure itself to show you different views of the data. You can interact with the pivot table at any time by dragging the fields around to modify the tables and graphs, or by hiding/showing information by clicking on the little triangles.

Let's get started!

The original dataset contained more than 4,000 unique request descriptions. The pivot table below is loaded with a partially-processed dataset: the requests have been grouped into 18 broad categories. You can find examples of the various descriptions, as well as a detailed explanation of the categorization process here. The chart below shows the distribution of requests by category; the categories are ordered by overall request volume.

Observations

• These categories span essentially all the non-emergency services the city manages, and can be compared to the city's 311 knowledge bank categories.
• Waste collection spans 3 categories: Selective Collection, Bulky Collection and Garbage Collection. Garbage Collection covers standard household waste; Selective Collection covers recycling and green waste; and Bulky Collection covers bulky items such as furniture and appliances.

On an administrative level, Montreal is divided up into 19 boroughs, some of which were merged into the city in 2002 and then reorganized in 2006. Below is the distribution of requests by borough and category. The boroughs are ordered by population. You can mouse over the bars to see which category is which and how many requests it represents within each borough. Click on the map for a handy reference.

Observations

• Saint-Laurent has the most requests, even though it's only the 8th most populous.
• At a high-level, it looks like there are notable differences in the distribution of categories among the boroughs.

In the table below, we are looking at the percentage of requests that each category represents within each borough. The redder the cell, the more that category preoccupied that borough.

Observations

• Bulky Collection is big in Rivière-des-Prairies–Pointe-aux-Trembles (see section 10).
• Security lights up for Saint-Laurent and L’Île-Bizard–Sainte-Geneviève (see section 7).
• Selective Collection lights up for Saint-Laurent (see section 9).
• Taxes light up in LaSalle and Saint-Léonard (see section 11).
• The fact that Other lights up in Montréal-Nord and Saint-Laurent suggests maybe the categorization scheme is missing important request types in those areas.

In the table below, we are looking at the percentage of requests that each year represented within a category. The redder the cell, the more requests in that category occurred in that year.

Observations

• Overall request volumes were relatively constant year over year.
• Security exhibits a steep decline during 2010 (see section 7).
• Parking also exhibits a steep decline during 2010 (see section 8).
• Selective Collection has a spike in 2012 (see section 9).
• Bulky Collection has a spike in in 2008 (see section 10).
• Snow also has a spike in in 2008, likely because Montreal saw 342 cm of snow that year, compared to roughly 200 cm per year over 2009-2012.

In the table below, we are looking at the percentage of requests that each month represented within a category. The redder the cell, the more requests in that category occurred in that month.

Observations

• Overall request volume is high in summer, low in winter.
• Snow is big in winter and absent in summer, unsurprisingly.
• Taxes spikes in February (see section 11).
• Environment spikes in May (see section 12).

The Security category stood out in both time and space (a large percentage of the requests in Saint-Laurent and L’Île-Bizard–Sainte-Geneviève, and as being much higher in 2008/2009 than in 2011/2012), so let's take a closer look. In the graph below we have Security requests by borough over time by month. We see a dramatic pattern: almost the entire change in request volume over the years is due to Saint-Laurent. Looking closely, L’Île-Bizard–Sainte-Geneviève also displays a cyclical pattern with more requests in summer. You can click on Saint-Laurent in the legend to hide that borough's line and see the others more clearly.

Analysis

• Most of the requests which comprise the anomalous line in 2008-2010 in Saint-Laurent have the same description ("20 - Surveillance particulière") and many are about a handful of addresses, usually of parks. As mentioned in the Gazette article, Saint-Laurent has a private security force which uses the 311 system to record some of its activities. Perhaps this practice stopped in April 2010.
• We have no clear explanation for the cyclical pattern in L’Île-Bizard–Sainte-Geneviève but the requests all have the same description: "Surveillance et sécurité publique".

The Parking category stood out as being much higher in 2008/2009 than in 2011/2012. Taking a closer look at just that category we can pin-point the change in May/June 2010, and we can see that unlike the Security category, it is not a case of a single anomalous borough, but rather spread out across many boroughs.

Analysis

• In the underlying dataset, the description of the requests which stopped appearing in June 2010 was "Intervention stationnement", suggesting a change in city policy at that time.
• Interestingly, in this case the Saint-Laurent borough again stands out as having more requests in this category than others in 2010-2012 but no requests from that borough had the "Intervention stationnement" description.

The Selective Collection category stood out as spiking up in 2012 and being a big percentage of the requests in Saint-Laurent. Taking a closer look, we can see that Saint-Laurent figures prominently, but in small spikes throughout the period. Additionally, we see that the rise in 2012 occurs across all boroughs starting in April/May.

Analysis

• The 2012 jump in this category is entirely due to requests described as "Environnement - Collecte de branches d'arbre", likely due to a change in city policy regarding tree branches as a result of the emerald ash borer infestation.
• Saint-Laurent spikes occur in October/November and are related to green waste bags, which are perhaps distributed to citizens at the same time each year. Interestingly, there is no such spike in 2009 or 2010.

The Bulky Collection category stood out as being a huge percentage of the requests in Rivière-des-Prairies–Pointe-aux-Trembles and as spiking in 2008. Taking a closer look, RDP-PAT dominates throughout the 5-year period, but we also see the smaller pattern of every borough having more requests about this in 2008. If you look closely, you will see that there are also regular spikes in this category of requests in May and September in Lachine

Analysis

• As mentioned in the Gazette article, in some boroughs such as Rivière-des-Prairies–Pointe-aux-Trembles, bulky waste is not collected unless a specific request is made, so perhaps this borough is much stricter about this policy and the result is a higher volume of requests.
• Perhaps more boroughs had such a policy up until 2009, which might explain why many of them had more Bulky Collection requests in 2008 than in other years.
• The periodic Lachine spikes are also likely due to a specific policy in that borough.

The Taxes category stood out as spiking in February, and as being a big deal in LaSalle and Saint-Léonard. Taking a closer look, we see that most boroughs have a spike in February, but that Saint-Laurent, Saint-Léonard and LaSalle have a different pattern that spikes in April and tails off more slowly.

Analysis

• The punctual spikes in this category are due to the timing of city correspondance about municipal taxes, and it's likely that the three anomalous boroughs just have a different schedule for these things. The three outliers were independent municipalities until 2002, and they share a request description not found in the other boroughs: "Changement d'adresse - Taxes eau et déchets".

The Environment category stood out as spiking in the month of May. Taking a closer look, we can immediately see that the May spike is solely due to Saint-Laurent. There is also a smaller pattern of spikes in March in Le Sud-Ouest, and some spikes in Ville-Marie, Rosemont–La Petite-Patrie and Pierrefonds-Roxboro.

Analysis

• All of the May spikes in Saint-Laurent can be explained by one request description: "Maisons fleuries". This relates to a contest held yearly in Saint-Laurent.
• The spikes in Le Sud-Ouest are all described as "Jardins - Renouvellement", which makes sense as a seasonal event.
• The increase in requests in 2012 (and the spike in November 2011) in Ville-Marie is entirely accounted for by requests related to graffiti.
• The spike in Pierrefonds-Roxboro in late 2012 is entirely accounted for by requests related to (presumably temporary) car shelters.
• The spike in Rosemont–La Petite-Patrie is related to the Eco-quartier program.

This analysis began with an overview chart of requests volumes by category (replicated below) and then proceeded to look at places and time periods where request volumes deviated from this overall pattern. Most of the deviations turned out to be attributable to seasonal effects or borough-specific policies or differences in the way in which different boroughs use the Gestion des demandes clients (GDC) system. In the aggregate, however, most of the time and in most places, the distribution of requests does follow the overall pattern, so we can look at the chart below and conclude that it more or less sums up the bulk of the service requests in the GDC system. That said, there may be more subtle patterns and stories of interest in the "Other" category, which represents 6.5% of the requests.

Beyond looking at types of requests over time and space, it would certainly be interesting to examine the outcomes of service requests, for example what was done in response to a request and how long it took or how much it cost, but unfortunately this information was not present in the dataset obtained by the Gazette.

Questions, feedback or comments on this analysis are welcome by email at nicolas@kruchten.com!