*2.2. Data Processing*

The current project was based on two scales of analysis. The first is at the metropolitan level, which aims to highlight and demonstrate the diverging levels of accessibility in the MMZ and relate them to relevant urban planning paradigms and socio-economic indicators such as the marginalisation levels. The second is at the local level, considering the Distrito Tec Area. Here, the objective was to analyse the accessibility levels to main employment centres, schools, supermarkets, and hospitals, travelling by foot or bicycle, to determine whether the area can be, or not, considered as a 15 minutes city.

For the current analysis, UrMoAC was programmed to start the measurement from urban blocks (origins) to several different destinations (hospitals, schools, supermarkets, and main employments centres). It is important to mention that there are socio-economic factors, such as social preference and willingness to pay, that can affect the decision of people to access one destination over another. Specifically, higher-income social groups tend to prefer private hospitals and schools to fulfil their health and education needs. In contrast, public services usually have access limitations related to the capacity of the building, level of service, entitlement, opening hours, working days, demand, among others. Including all these variables in the analysis goes beyond the scope of work from the current research project, as it aims to provide a preliminary approach to urban accessibility based on the supply of land uses and transport networks at different scales. In this sense, only public hospitals and schools were taken into account, embracing the idea that public establishments are available for everyone despite their income.

The transport modes used for the computation were either walking (with an average speed of 3.6 km/h) or bicycle (average speed of 12 km/h) to analyse to what extent the MMZ is ready to shift from car-oriented mobility to generating accessibility through micromobility and proximity-based land use planning. The aforementioned average speeds for each transport mode are the ones proposed by the UrMoAC tool [10]. Public Transport was not considered as it requires General Transit Feed Specification (GTFS) data files to run the accessibility computation, which are not currently available for the areas of study analysed in this work.

As mentioned before, the computation was designed to start every measurement from urban blocks. Depending on the measurement desired, the destinations would vary considering either: the closest available, a specific number of destinations that can be reached (e.g., the five nearest hospitals), or with a 15 min travel time constraint to see how many destinations are available within that travel time. The reasons for generating different measurements were to demonstrate UrMoAC's capacity to compute diverse and relevant results, to integrate social and capacity factors into the measurement (e.g., one school alone cannot fulfil the entire education demand of a given district; therefore, more than one has to be included) and to analyse the results from different approaches that provide useful insights about the accessibility of the study area.

For the results to be legible, understandable, and useful, the individual results from each block were aggregated into Basic Geostatistical Areas (AGEBs, by its acronym in Spanish) and then mapped. The AGEBs are the basic aggregation areas used by the National Institute of Statistics and Geography (INEGI, by its acronym in Spanish) census; therefore, they are an unit of analysis widely used for mapping purposes in Mexico.

For the realisation of this project, the following data were gathered: a compendium of the urban geostatistical cartography of Nuevo León (Mexico) state (from 2016, as it is the most recent version), the urban block subdivision of the 18 municipalities that form the MMZ, the National Statistical Directory of Economic Units 2019 (DENUE, by its acronym in Spanish), and the OpenStreetMap road network from 2021.

Table 1 shows the databases of the variables (municipalities, blocks, AGEBs, DENUE, and roads), the institutions, and the URLs for all the gathered data in this study.

**Table 1.** Databases and URLs of the used resources in this study.


The DENUE is elaborated by INEGI and offers a large compendium of all the economic activities registered within the Mexican territory, which can be categorised according to the North American Industry Classification System (NAICS). The NAICS is a standard created to allow high comparability in business statistics among North American countries (Canada, USA, and Mexico). For this study, the categories displayed in Table 2 were analysed.

**Table 2.** Categories of the analysed economical activities, according to the NAICS.


For the metropolitan-level analysis, the following accessibility measures were performed: number of employments centres with 51 or more employees accessible within

a 15 min travel time, the distance and time to the nearest public school (including all levels from preschool to high school), and nearest hospital (including codes 622112, 622212 and 622312).

For the Distrito Tec's analysis, the computations were: number of employment centres with 51 or more employees accessible within a 15 min travel time, the number of retail trade supermarkets available within a 15 min travel time, and the time required to access the five nearest schools or hospitals; here, an individual study was conducted for each category mentioned in Table 2.

The aforementioned measurements were evaluated under the following (see Table 3) criteria, which were determined in compliance with each transport mode's average speed (according to UrMoAC) and the cumulative opportunity accessibility metric (where more opportunities in the surroundings relate to higher accessibility levels) [17]. It is important to highlight the complexity of a standardised rating scale for the number of destinations reachable within a specific time or distance, when comparing different services, as socio-economic and demographic features must be considered to develop an accurate measurement. Therefore, the current research project performed a preliminary approach and diagnosis by evaluating the number of destinations available within a 15 min travel time either by bicycle or walking. Comparisons of accessibility across different services were not evaluated.

**Table 3.** Standardised rating scale.

