The OMAI Model

For the additions to this field guide during the summer of 2021 our class decided to utilize the OMAI model to assess our sites. This model was developed by Langstraat and Van Melik as a way to analyze the “publicness of urban public space.” In Challenging the ‘End of Public Space’: A Comparative Analysis of Publicness in British and Dutch Urban Spaces the authors use this model to analyze the idea that public spaces are coming to an end or are at least threatened by privatization. This is something that was on all of our minds as we assessed our spaces. They believe their model provides a clearer way to allow for comparison of different spaces. Our class appreciates this point as well as the clarity of the dimensions of the model itself.

The four dimensions of this model are as follows:

  1. Ownership. This dimension is the clearest and refers to the legal status of a place (privately owned, city owned, etc.).
  1. Management. This includes daily care of the space as well as any presence of control such as CCTV and security guards.
  1. Accessibility. The two main parts of this dimension are how a space is connected to its surroundings and the physical design of it. Accessibility accounts for any physical and legal barriers to access. These could include things like locked gates, non-wheelchair accessible stairs, or guards who require an ID or ticket for entry.
  1. Inclusiveness. This dimension refers to how well the space meets the demands of the population. This can be indicated by the diversity of its users and how welcoming the space feels.

Each of these dimensions are ranked from 1 to 4; 1 indicates a space is fully private while 4 suggests a fully public space. 

Class Methodology & Example 
The OMAI model is visualized using a pie chart that divides each dimension of publicness into an equal section of the circle. Within the circle are three lines creating four smaller circles within the chart. Langstraat & Van Melik explain “…a bigger ‘slice’ represents a more ‘public’ space; a small slice stands for a more private space in that particular dimension. The concentric rings allow each of the four dimensions to be measured on an ordinal, four-point scale ranging from 1 [fully private] to 4 [fully public].”

To implement the model in our own case studies, each student referred to the detailed table from Langstraat and Van Melik’s research for consistency across our analyses. Using the table’s 1 (fully private) – 4 (fully public) scale, one would shade in the corresponding number of lines within a given sector. After assessing each of the four dimensions of publicness, each section of the chart will display a shaded section that may prove consistent with or divergent from the other sections within the chart. A fully shaded-in section is considered ‘fully public,’ while a section with very minimal shading is considered ‘fully private.’ 

In order to better visualize how this process works, below is an example of the OMAI model in practice using the Macalester College Great Lawn as a test subject. 

OMAI model evaluation of Macalester’s Great Lawn and Key to interpreting the OMAI model

After several visits to the site to establish a comprehensive sense of the lawn’s publicness, we are able to employ the model as a means of visualizing each of these four dimensions. 

Starting in the top left, we categorized Ownership as a 1, indicating that it is fully private. In other words, “legal ownership rests solely with a for-profit organization that is not publicly accountable.” We can deduce this based on the fact that the Macalester lawn is owned by a private college and is not accountable to any public entities. 

We categorized Management as a 1, as well, indicating that it is fully private. This indicates that the lawn has a daily security and maintenance presence, both of which are provided for the space by an independent private party, Macalester College. There is also the presence of discrete surveillance cameras. 

We categorized Accessibility as a 3, or ‘public with some private characteristics.’ Within the OMAI model, this indicates that the space meets some but not all of the criteria of category 1: ‘Physical barriers to access; a visually inaccessible design, resulting in a stealthy space’, a geographical location that makes it difficult for certain groups to reach the space; lack of accessibility by public transport.’ While the lawn is in close proximity to several major public transit lines, it fails to provide publicly accessible amenities such as restrooms and water fountains. 

And finally, we categorized Inclusiveness as a 2 because ‘seating and lighting are available, but no other attempts are made to welcome non-consuming visitors, and a restrictive policy on activities allowed is still in place.’ In this example, we will categorize all non-Macalester students and faculty as the ‘non-consuming visitors’ for whom the Macalester lawn is less inclusive. And while seating and lighting are made available, we know that the college regulates what kinds of activities can take place on the lawn, and even for Macalester students and faculty, this regulation is often extremely restrictive.

Now that you’ve read how our class employed the OMAI model, use the following worksheet to evaluate spaces near you.