Nowadays, food establishments such as restaurants have become part of our daily lives. Chicago is a great example of a big city which gathers a huge variety of such establishments. As such, we focus our project on facilities located there.
In this project, we firstly try to understand which factors are most at stake when talking about food safety in food establishments in Chicago. In the process, we also take a detour and use socio-economic indicators of Chicago community areas in order to see if eating safely is equally accessible to all members of society. To this end, we will see whether our dataset supports the existence of food deserts in Chicago.
Our ultimate aim is to promote public health by computing a Safety Score based on information from inspections as well as other metrics that prove useful during analysis. The Chicago residents can use this score to safely decide where to eat out.
Our starting point is the Chicago Food Inspection data set, which contains information about the inspections of food establishments in Chicago from January 1, 2010 up to the present. As we will see further down, each inspection is accompanied by information about the inspected facility such as its location and its type (restaurant, medical establishment, school...). The inspection outcome depends on whether the establishment was found to have any of the 45 possible violations, and in this research we consider the following results:
In this part of our research, we got familiar with how inspection outcomes differ according to various establishment and inspection features. We also examined and analyzed the performance evolution of facilities in Chicago.
Does the type of an establishment influence its inspection outcome?
Some insights:
Food cleanliness is a top priority in the medical world and there is no room for error. Medical establishments can not get passes with conditions: they either pass or fail the inspections. This strict approach might explain why they have the highest proportion of fails.
Are reinspections always a success?
Reinspections correspond to inspections that establishments get for a second time, typically after a fail.
Some insights:
The proportion of facilities which get a pass in their reinspection is bigger than that which get a pass at their first inspection. This makes sense as establishments take into consideration the comments given by the inspectors before their reinspections.
We can also see that the proportion of passes with conditions is smaller for the reinspections. This makes sense as giving such a result would mean giving establishments "a third chance".
Each establishment is classified into one of three risk categories according to its likelihood of affecting the public’s health. Category 1 being the highest in terms of risk and 3 the lowest. The inspection frequency is tied to this risk.
Some insights:
Surprisingly, the riskiest establishments seem to get the least fails. This might be due to their awareness of the matter and hence their care in maintaining their sanitation.
Establishments with the highest risk also get the highest proportion of passes with conditions. This could mean that inspectors might be less severe with them given that it is very challenging to maintain such a risky establishment.
The proportion of passes seems independent of the risk of the facility.
There are several stereotypes about certain cuisines being riskier than others. However, the food inspection results might surprise you...
Does pricier imply safer?
Some insights:
We would expect the cheapest restaurants to have the highest fail proportion. But this is not the case: the price range actually does not influence inspection outcomes.
Ratings given by the community certainly reflect the establishments quality, but they do not always reflect the inspection outcomes. For instance, establishments with a 4.5 rating have more failed inspections than establishments with a 4.0 rating.
We often expect to find diverse and numerous food places in big cities. However, we found that in some areas of Chicago, residents are lacking access to healthy and affordable food options due to the absence of grocery stores within convenient travelling distance. This phenomenon is referred to as a food desert, a.k.a. food apartheid. Further, in a report by the Illinois Advisory Committee to the United States Commission on Civil Rights, it is stated that these food desert neighborhoods are almost exclusively in African American neighborhoods making the issue a civil rights one beyond its public health dimension.
Let's take a look at establishments that represent healthy food providers (grocery stores, farmer's markets, fish markets, meat markets...). We retrieve these establishments from the inspection dataset1 and plot their density by surface for Chicago's community areas.
We certainly see a difference in the concentration of grocery stores between the North and the South, the south being quite sparse.
“Chicago’s segregation is certainly legendary, with the North and South sides divided by class and race. To keep it stereotypically simple: The North Side is white, the South Side is black.”
- Ashok Selvam, Senior Editor Eater Chicago
Chicago is the perfect example of a melting pot, with almost even proportions of African American, White and Latino people and a minority of Asians. However, the map below shows us that there is a clear separation between the North and the South, the South having mostly African American neighborhoods, the North mostly White neighborhoods and the West Latino neighborhoods.
As we can see below, the grocery stores' density is positively correlated with Population Count by community area as well as with Per Capita Income. It is on the other hand negatively correlated with Below Poverty Level. These observations make sense if we think about grocery stores wanting to maximize their profit.
"Grocery stores typically have only 1-2% profit margins, so the difficulties involved in running an urban supermarket are often seen as too costly in an already-risky business."
A solution that the Illinois State could put into practice is the one implemented in the state of New York: "providing zoning and financial incentives to grocery stores in underserved communities".
We compiled a technical score for several food establishments in Chicago. This score heavily depends on the violations committed at the time of inspection (e.g. whether they were critical or not).
Critical violations include improper personal hygiene or rodent and/or insect infestation. Serious and moderate violations include no proper protection from contamination or poorly constructed walls. The score takes into account the severity of critical violations and hence gives bigger weights to the attributes linked to them. It also takes into account whether there were cases of food poisoning caused by the establishment, or if there were any "hidden allergens" in the establishment. The pie chart below showcases the different weights given to the parameters we use to compute our score.
The final score takes into account the opinion of the Yelp community by using the average user establishment rating. The map below showcases the final score. Simply use the slider to select the importance attributed to the user rating.
For example, selecting 0% will result in a total score that is equal to the technical score, whereas selecting 100% will result in a total score that is the user rating.
Our final score follows this simple formula.
This research has allowed us to uncover many insights into food establishments in Chicago.
Firstly, we found the features which affect food establishment inspection outcomes the most, a result which could be arguably generalized to many other cities. This has also enabled us to argue against stereotypes in some cases such as stereotypically "less clean" cuisines.
Next, we took a look at the interesting phenomenon of food deserts. We have indeed found that our data set supports the claim that such deserts do exist in Chicago. We hope that in the future, initiatives such as the NYC one will be implemented in Chicago.
Finally, we computed a safety scores for food establishments and displayed them on a map which could be used by users to be able to eat safely in Chicago.