In the current international context, cities are taking on a new role and leadership as they have become nodes that organize and articulate the global economy. Nowadays, the world is experiencing the largest wave of urban growth ever registered, from which new multidimensional challenges are emerging such as: sustainability, resilience, climate change, inequality, migration, urban sprawl and urban services (UN 2016). Therefore, a new holistic and analytic approach is necessary, with innovative views to enhance the cities’ management and performance. To deal with these new challenges, the concept of smart city appears as an opportunity for management and urban planning.
In this new socio-technological urban model, indexes methodologies and city metrics emerge as an interdisciplinary tool, from local to global, from citizens to managers, through society, institutions, new technologies, infrastructures, planning and urban services. They have become an essential tool to asses, measure and represent how the use of ICT can sway the city’s management and the improvement of the citizen’s quality of life.
During the last couple of years, the use of indicators has increased across public and private sector systems being used to monitor and assess different urban domains such as sustainability, quality of life, competitiveness and other urban services. The number of cross-cutting projects and interdisciplinary working groups that addresses this topic has multiplied. They have turned into a global phenomenon thanks to the growing interest in evaluate the performance of strategies for urban planning. Every year there are more indicator methodologies that cover a higher number of urban topics as there are more datasets available about cities: from global data sources, specialized metrics, open real-time service websites and other private databases, to data obtained through local surveys about citizen’s perception.
Around city metrics we can differenciate two main zones (see Fig. 1): Stakeholder and Datasets. The first ones work as their main developers from different angles and they assemble in private entities such as consulting groups, technological companies and international institutions, or in public entities such as universities, local administration or civil society associations, or in public-private partnership collaborations. The second ones fix and limit the indicators content and capacity, as they feed them. They are grouped in both open data and statistical repositories platforms of various scopes.
The disintegration of domains, types and construction of indicators and the contextualization based on each city morphology becomes important in this ecosystem. Taking into consideration all the above, the following methodology types can be summarized:
- Indicator: understood as a recurrent quantified measure that can be traced over time to provide information to a particular event (Godin 2003)
- Index: understood as an ensemble of objective data from a specific city field through recurring measurements in time.
- Benchmarking: understood as a comparison of indicators sets between cities to recognize and to establish differences over a topic.
- Ranking: understood as an order list, not comparative throughout time, of cities that reflect the specific state over a topic based on some given indicators.
- Rating: understood as a qualification of cities based on the subjective score of a topic. It provides an acknowledgement over a performance.
The urban indicator systems are an important step towards homogenization and characterization of measurements and comparison between cities. City benchmarking compares and ranks the relative city performances. Nowadays, cities are seeking to complement and increase their indicator sets through ICT technologies in real-time data. Even more recently, for the sake of transparency, some of them share with citizens interactive open data visualization dashboards, providing descriptive information about city performances and tendencies.