Smart city indexes, criteria, indicators and rankings: An in‐depth investigation and analysis - Toh - 2022 - IET Smart Cities - Wiley Online Library

1 INTRODUCTION

According to World Urban Forum [1], there are 10,000 cities in our world today. In China alone, there are over 800 smart city pilot programs [2]. India has over 5000 smart city projects commissioned throughout the country. The explosive growth and attention given to smart cities are clear and undeniable. Countries governing the world economy, including the G20 nations, all have some sort of on-going smart city projects. But what exactly is a smart city? According to ITU [3], a smart city is defined as:

“A smart sustainable city is an innovative city that uses information and communication technologies (ICTs) and other means to improve the quality of life, the efficiency of urban operation and services, and competitiveness, while ensuring that it meets the needs of present and future generations with respect to economic, social and environmental aspects”.

With all these smart city developments happening, several organisations (including universities and private consultancy companies) are evaluating and ranking global cities. Yearly, top smart cities are ranked and announced in the news and online media. While some city governments have utilised such rankings [4], it is unknown how widely accepted these rankings are by other city governments and city residents. Also, there remains scepticism about smart city rankings, especially on their neutrality, accuracy, reliability, and methods of measurement and comparison. Currently, there is no international organisation that focusses on producing a universally agreed and accepted form of smart city index and ranking. Some new indexes have emerged but are limited in scope and utility [5] while others [6, 7] have been around for decades.

While the UNECE (United Nations Economic Commission for Europe) has produced a 134-page report on a collection of methodologies for key performance indicators for smart sustainable cities (SSC) in 2017 [8], few organisations have adopted and used it. In addition, UNECE does not score and rank global cities. Currently, different organisations (universities and companies) have produced their own rankings based on their own selected criteria and measurement methods. Having too many indexes and rankings produced by different organisations do not help world governments, policy makers or the public community to understand which is useful, correct and can be used as a reference. In fact, too many indexes and rankings add to confusion and result in tedious work in reading through lots of reports and understanding all existing city indexes and rankings. This is, therefore, not a scalable situation.

Hence, this forms the motivation of this paper, that is, to look into the six existing major smart city indexes and their rankings, highlighting how they address existing problems, how they perform their measurements, comparisons and rankings. Comparisons are then made on these 6 smart city indexes to yield further insights and recommendations. These six indexes and rankings are chosen because they are produced by major organisations, not individual researchers, and their reports are produced and made available annually.

2 CURRENT INDEXES

In this paper, the author examines 6 major indexes and rankings. They are (1) IMD-SUTD Smart City Index, (2) AT Kearney Global Cities Index, (3) IESE Cities in Motion Ranking (CIMI), (4) Cities of the Future Index (CFI) by EasyPark Inc., (5) Mori-Foundation Global Power City Index (GPCI), and (6) SECI Index by SmartEcoCity Ltd.

2.1 The IMD-SUTD smart city index (I-SCI)

The IMD-SUTD [REF4] introduces a smart city index to capture the economic, humane and technological aspects of smart cities. The humane aspects refer to quality of life, environment, and inclusiveness. To derive this index, IMD-SUTD performed survey on hundreds of citizens from 118 cities in July 2021 and asked questions on their cities across 2 categories, that is, structures and technology and within each category; there are 5 key criteria to be evaluated, namely (a) health and safety, (b) mobility, (c) activities, (d) opportunities and (e) governance.

IMD-SUTD then introduces a methodology for quantifying the performance of a smart city. The Human Development Index (HDI) is used. The United Nations has created HDI to include people and their capabilities as the ultimate criteria for assessing the development of a country, not just economic growth factor alone. As shown in Figure 1, HDI has three elements, namely:

(1)
life expectancy at birth,
(2)
expected years of schooling and mean years of schooling, and
(3)
GNI (Gross National Income) per capita [9].

Details are in the caption following the image — **FIGURE 1**
Open in figure viewer PowerPoint

Human development index (source Ref. [9])

The GNI per capita is used to reflect the standard of living in the city.

In the IMD-SUTD approach, cities are first classified into 4 groups based on the HDI scores. Then within each HDI group, cities are assigned a ‘rating scale’ (AAA to D, 4 grades) based on the perceptions-score of a given city, compared to the scores of all other cities within the same group. Scores for each component of the structure and technology category are done numerically. The scores are obtained from residents who had participated in the city's survey. Structures refers to existing infrastructure of the cities while technology refers to technologies and services available to residents. Both structures and technology applications category are evaluated over 5 key criteria: (1) health and safety, (2) mobility, (3) activities, (4) opportunities, and (5) governance. As shown in Table 1, different questions are asked for each component of structures and technology. Under health and safety, questions asked in the structures category are related to sanitation, recycling, public safety, air pollution, medical services and housing. But for the technology category, the questions asked are related to city maintenance problems, mobile app for residents to give away unwanted goods, public WiFi, CCTV for public safety, app to monitor air pollution, and online reservations of medical appointments. It is unknown and unclear why these questions are chosen and why they are considered representative for each key criterion. Further justifications are therefore necessary.

TABLE 1. The specific components of STRUCTURES and TECHNOLOGY groups in IMD-SUTD SCI index. Within each group, there are 5 criteria and 39 indicators

STRUCTURES	Technologies
■ Health & safety	■ Health & safety
• Basic sanitation meets the needs of the poorest areas	• Online reporting of city maintenance problems provides a speedy solution
• Recycling services are satisfactory	• A website or app allows residents to easily give away unwanted items
• Public safety is not a problem	• Free public wifi has improved access to city services
• Air pollution is not a problem	• CCTV cameras has made residents feel safer
• Medical services provision is satisfactory	• A website or app allows residents to effectively monitor air pollution
• Finding housing with rent equal to 30% or less of a monthly salary is not a problem	• Arranging medical appointments online has improved access
■ Mobility	■ Mobility
• Traffic congestion is not a problem	• Car-sharing apps have reduced congestion
• Public transport is satisfactory	• Apps that direct you to an available parking space have reduced journey time
	• Bicycle hiring has reduced congestion
	• Online scheduling and ticket sales has made public transport easier to use
	• The city provides information on traffic congestion through mobile phones
■ Activities	■ Activities
• Green spaces are satisfactory	• Online purchasing of tickets to shows and museums has made it easier to attend
• Cultural activities (shows, bars, and museums) are satisfactory
■ Opportunities (work & school)	■ Opportunities (work & school)
• Employment finding services are readily available	• Online access to job listings has made it easier to find work
• Most children have access to a good school	• IT skills are taught well in schools
• Lifelong learning opportunities are provided by local institutions	• Online services provided by the city has made it easier to start a new business
• Businesses are creating new jobs	• The current Internet speed and reliability meet connectivity needs
• Minorities feel welcome
■ Governance	■ Governance
• Information on local government decisions are easily accessible	• Online public access to city finances has reduced corruption
• Corruption of city officials is not an issue of concern	• Online voting has increased participation
• Residents contribute to decision making of local government	• An online platform where residents can propose ideas has improved city life
• Residents provide feedback on local government projects	• Processing identification documents online has reduced waiting time

For the year 2021, I-SCI ranks 118 cities globally by capturing the perceptions of 120 residents in each city. The final score for each city is computed by using the perceptions of the last 3 years of the survey, with the weight of 3:2:1 for 2021:2020:2019. Hence, a city's previous performance does affect its current ranking. While this chosen weightage reflects progression, it may not favour cities who had not done well in previous years but have progressed tremendously in the current year. The ratio of 3:2:1 clearly shows the previous 2 -year performance equates to the same weightage as the current year. To prove this, we highlight the top 10 rankings of cities done by IMD-SUTD for the last 3 years since its inception (see Table 2). Clearly, Singapore and Zurich have consistently stayed in the top two places. Note that London, New York, and Paris are missing from the 2021 and 2019 rankings.

TABLE 2. IMD-SUTD city rankings. Singapore and Zurich have consistently stayed in the top 3

As mentioned earlier, within each HDI group, cities are given a ‘rating scale’ (AAA to D), based on the perception scores of a given city compared to the scores of all other cities. Hence, the grading is a relative score, against the scores of all other cities. For group 1 (highest HDI quartile), the scale is AAA–AA–A–BBB–BB. For group 2 (second HDI quartile), the scale is A–BBB–BB–B–CCC. For group 3 (third HDI quartile), the scale is BB–B–CCC–CC–C and finally, for group 4 (lowest HDI quartile), the scale is CCC–CC–C–D. As shown in Table 3, a score of AAA in structure and technology for Singapore in 2021 yields an effective grade of AAA. But for Zurich and Oslo, an AAA for structure and A for technology yields an AA for the effective grade. Although both Zurich and Oslo have the same effective grade of AA, Zurich is ranked higher than Oslo due to its previous ranking in 2020 (Zurich 3^rd while Oslo 5^th). IMD-SUTD Index is a relatively young index and has not yet been widely accepted.

TABLE 3. ITU-SUTD top 15 city rankings for 2021 based on evaluating structures and technology in each city and their past rankings (Source: Ref. [10])

Smart city ranking for 2021	City	Smart city rating 2021	Structure 2021	Technology 2021	Smart city ranking for 2020	Change
1	Singapore	AAA	AAA	AAA	1	–
2	Zurich	AA	AAA	A	3	+1
3	Oslo	AA	AAA	A	5	+2
4	Taipei city	A	A	A	8	+4
5	Lausanne	A	AAA	A	–	–
6	Helsinki	A	AA	A	2	−4
7	Copenhagen	A	AA	A	6	−1
8	Geneva	A	AA	A	7	−1
9	Auckland	A	A	A	4	−5
10	Bilbao	BBB	A	BBB	24	+14
11	Vienna	BBB	A	BB	25	+14
12	New York	BBB	BB	BBB	10	−2
13	Seoul	BBB	B	A	47	+34
14	Munich	BBB	AA	BBB	11	−3
15	Zaragoza	BBB	A	BB	48	+33

2.2 AT Kearney Global Cities Index (GCI)

The second index to be discussed is the Global Cities Index (GCI) [11] introduced by the company AT Kearney. It is one of the oldest existing smart city indexes introduced, starting from 2008. As shown in Table 4, GCI measures how globally engaged cities are using 29 indicators across 5 criteria, namely (1) business activity (30%), (2) human capital (30%), (3) information exchange (15%), (4) cultural experience (15%), and (5) political engagement (10%).

TABLE 4. GCI uses 5 Criteria and 29 indicators to evaluate global cities

Business activity	Human Captial	Information exchange	Cultural experience	Political engagement
1. Fortune 500	1. Foreign born population	1. Access to TV news	1. Museums	1. Embassies and consulates
2. Top global services firm	2. Top universities	2. New agency bureau	2. Visual and performing arts	2. Think tanks
3. Capital markets	3. Population with tertiary degree	3. Broadband subscribers	3. Sporting events	3. International organisations
4. Air freight	4. International student population	4. Freedom of expression	4. International travellers	4. Political conferences
5. Sea freight	5. Number of international schools	5. Online presence	5. Culinary offerings	5. Local institutions with global reach
6. ICCA conferences	6. Medical universities		6. Sister cities	5. Local institutions with global reach
7. Unicorn companies

In GCI, cities are ranked according to all 5 criteria. These 5 criteria are elaborated below. Business activity refers to a city's capital markets, the number of Fortune 500 companies headquartered there, the number of international conferences held there, the flow and volume of goods that pass through the city. This was given a weightage of 30%, reflecting that a city's economy is almost a third of the total score. Human capital refers to how well a city attracts diverse talents. This includes the number of foreign-born population, quality of universities, number of international schools, number of university degree graduates, and number of international students. This criterion carries a weightage of 30%, on par with that of a city's economy, and recognising the importance of people in the city. The information exchange dimension refers to how well information is disseminated within and outside the city. Hence, it includes the number of international news bureau, the level of censorship, the proportion of international news in local newspapers, and the broadband (Internet) subscription rate. This criterion is given a weightage of 15%. The fourth criterion is cultural experience. This refers to the variety of attractions for city residents and foreign visitors, such as sports events, museums, arts evets etc. This carries a weightage of 15%. Finally, the fifth criteria is political engagement. This refers to the degree where a city can influence global policy-making and dialogues. Specifically, this criterion measures the number of embassies, consulates, think-tanks, international organisations, and the number of political conferences a city host. This criterion has a weightage of 10%. GCI derives sources from publicly available city data. Based on computed numeric scores, cities are then ranked.

In the recent AT Kearney 2021 Global Cities Report, GCI has included a city's responses to COVID19 as part of the evaluation, such as resilience and adaptive capacity. However, it was not mentioned which criterion has included this. Up to 156 cities are considered in the 2021 ranking. Since GCI has started its ranking since 2008, it is meaningful to look at its rankings over the 11-year period. As shown in Table 5, New York, London, Paris and Tokyo have consistently been ranked in the Top 4 places. Hong Kong has consistently stayed in the 5^th place, with the exception of 2021 and 2020. Los Angeles has also been consistently staying at the 6^th place, with the exception of 2017, 2019, and 2020. However, it moves up to the 5^th place in 2021. Singapore was first ranked on the 7^th place in 2008, but has gradually moved down to 9^th place (2014), 8^th place (in 2015 ans 2016), 6^th place (2017 and 2019) and finally settled on the 9^th place (2020 and 2021).

TABLE 5. 2021-2008 Global Cities Index (GCI) rankings. From 2017 to 2021, New York, London, Paris and Tokyo have consistently been ranked as the top 4 cities

Acronyms: SG: Singapore; WAS: Washington D.C. Note: No rankings for Year 2013, 2011, and 2009.

An interesting point to note is that Beijing has risen to displace Hong Kong, being ranked 5^th place in 2021. For a period of 11 years, GCI ranking for the top 5 cities have been quite consistent, and it has included Asia Pacific cities (Tokyo, Hong Kong, Singapore, and Seoul) right from its inception in 2008. Washington D.C., Brussels, Seoul, Toronto, Seoul, and Sydney have all dropped out of the top 10 ranking in 2021.

2.3 IESE Cities in Motion Ranking (CIMI) by IESE

IESE CIMI [REF:7] uses 9 criteria and 101 indicators to evaluate cities (see 6a), namely [1] human capital, [12] social cohesion, [9] economy, [10] urban planning, [2] environment, [11] international protection, [13] technology, [14] mobility and transportation, and [6] governance. IESE provides a thorough and comprehensive evaluation into each of the criteria, along with providing sources where data can be obtained for each indicator. Due to the excessive narration available for each indicator from IESE, this paper will only summarise the essentials. Readers can consult the reference for further reading.

TABLE 6. IESE CIMI uses 9 criteria and 101 indicators to evaluate global cities. [13]

Table 6a
1. Human capital	2. Social cohesion indicators	3. Economy
1. Secondary or higher education	1. Female friendly	1. Collaborative economy
2. Schools	2. Hospitals	2. Ease of starting a business
3. Business schools	3. Crime rate	3. Mortgage
4. Expenditure on education	4. Slavery index	4. Motivation that people have to undertake early-stage entrepreneurial activity
5. Per capita expenditure on leisure and recreation	5. Happiness index	5. Number of headquarters
6. Expenditure on leisure and recreation	6. Gini index	6. Purchasing power
7. Movement of students	7. Peace index	7. Productivity
8. Museums and art galleries	8. Health index	8. Hourly wage
9. Number of universities	9. Price of property	9. Time required to start a business
10. Theatres	10. Homicide rate	10. GDP
	11. Death rate	11. GDP per capital stimated GDP
	12. Female employment ratio
	13. Suicide rate
	14. Unemployment rate
	15. Terrorism

4. Urban planning	5. Environment	6. International protection
1. Bicycles for rent	1. Solid waste	1. Number of passengers per airport
2. Number of completed buildings in the city	2. Future climate	2. Number of hotels per capita
3. Number of people per household	3. CO₂ emissions	3. Restaurant index
4. Percentage of the urban population with adequate sanitation services	4. Methane emissions	4. Number of McDonald's restaurants per city.
5. Buildings over 35 m high	5. Environmental performance index	5. Number of international conferences and meetings that are held in a city.
	6. CO₂ emission index	6. Number of photos of the city uploaded online
	7. Pollution index
	8. PM10
	9. PM2.5
	10. Percentage of the population with access to the water supply
	11. Renewable water resources

Table 6b
7. Technology	8. Transport & mobility	9. Governance
1. 3G coverage	1. Bicycle rental	1. Government buildings
2. Innovation index	2. Moped rental	2. E Government development index (EGDI)
3. Internet	3. Scooter rental	3. Embassies
4. Online banking	4. Bicycles per household	4. Employment in the public administration
5. Online video calls	5. Bike sharing	5. Strength of legal rights index
6. LTE/WiMAX	6. Traffic inefficiency index	6. Corruption perceptions index
7. Mobile phone penetration ratio	7. Exponential traffic index	7. ISO 37120 certification
8. Personal computers	8. Traffic index	8. Research centres
9. Social networks	9. Length of the metro system	9. Open data platform
10. Landline subscriptions	10. Number of metro stations per city	10. Democracy ranking
11. Broadband subscriptions	11. High-speed train	11. Reserves
12. Telephony	12. Number of commercial vehicles in the city.	12. Reserves per capita
13. Mobile telephony	13. Number of incoming flights (air routes) in a city
14. Internet usage away from home and/or office
15. Internet speed
16. Web index
17. Wi-Fi hotspots

Human capital here refers to the level of education, access to culture and recreation. Social cohesion refers to the level of coexistence between groups of people in the same city with different income, culture, age and profession. Economy refers to strategic industrial plans, cluster generation and entrepreneurial initiatives. Urban Planning refers to the design and thought process where each necessary component required for the construction of a city is made. Planning allows a city to be efficiently constructed while fulfiling a high standard in the quality of life. Citizens, social organisations, public and private sectors, multilateral organisations and academia are all are important players. Environment concerns the sustainable developments of a city. It refers to the development that meets the needs of the present without compromising the ability and continuity of future generations. Green technologies, green buildings, renewable energy, efficient waste management, reliable water and fuel supply, and methods to counter climate change are essential. These measures determine the long-term sustainability of smart cities.

International projection refers to how a city project itself to the outside world. Hence, a city's reputation in the world is important. It needs to promote its brand, attract tourists to visit, attract foreign investments etc. Technology refers to technological penetration within the city. It includes the use of social media, personal computers, presence of high speed Internet and usage, wireless access (including WiFi and 5G) etc. Transport–Roads, highways, bridging infrastructures, public transportation, and air transportation impact the quality of life of city residents. They are crucial to business activities within the city too. Transportation for the last mile such as bicycle or motorbike rental services are increasingly popular. Governance describes the effectiveness, quality and guidance of city government's intervention. Good governance includes public and business leaders' participation.

IESE CIMI index was first started in 2014. Since 2020, it has taken into account COVID crisis and recovery. The 2020 index has included a total of 101 indicators to reflect both objective and subjective data and offer a comprehensive view of each city. The top 10 cities in 2020 are ranked based on CIMI numeric scores. They are 1. London, 2. New York, 3. Paris, 4. Tokyo, 5. Reykjavik, 6. Copenhagen, 7. Berlin, 8. Amsterdam, 9. Singapore, and 10. Hong Kong. As shown in Figure 2, London has scored highly for human capital and international outreach. For all other indicators except environment, it has mostly scored above 80. New York is strongest in economy, transport, and urban planning. Paris is strongest in international projection and transport. Finally, Tokyo is strongest in economy, technology and social cohesion.

As shown in Table 7, the global city rankings from 2014–2020 is tabulated and compared. From 2015–2020, the top 2 places have been London and New York but London has most recently been ranked top. The third city that has been frequently selected is Paris (except for 2019, 2015, and 2014). The fourth city has not been consistent but most recently it is Tokyo. In the fifth place is Reykjavik (for the last 3 years). For the sixth to tenth places, the chosen city was different in each year (except for the 9^th place, Berlin and Singapore had appeared twice; for the 10^th place, Amsterdam had appeared twice from 2014–2020). Hence, for the period of 7 years, New York and London are the two cities that have constantly been placed in the top two places.

TABLE 7. IESE CIMI rankings of global cities from 2014–2020

2.4 Cities of the Future Index (CFI) by EasyPark Inc.

Cities of the Future Index (CFI) [14] focusses on how cities are adopting new technologies to create a more sustainable and livable present and future for citizens. The CFI index is created by EasyPark Group, a company located in Stockholm, Sweden. The 4 criteria assessed by CFI are (1) digital life, (2) mobility innovation, (3) business technology infrastructure, and (4) sustainability, see Table 8.

TABLE 8. Factors within each criterion, with a total of 50 indicators to be scored on

1. Digital life	2. Mobility innovation	3. Business technology infrastructure	4. Sustainability
● Citizen Adoption (2)	● Parking innovation (5)	● Business Innovation (5)	● Green Energy (2)
1. Number of startups in the healthcare, lifestyle and Internet service sectors in each city, both in absolute terms and on a per population basis	1. The overall number of parking spaces per capita	1. Healthcare	1. Share of nationwide energy consumed from renewable sources
2. Number of app downloads and ranking in food, navigation, travel, education and financial services categories, excluding reference and utility apps	2. The number of parking spaces capable of accepting digital payments	2. Internet services	2. Share of electricity consumption from renewable sources
	3. The number of parking technology providers operating in the city	3. Financial services
	4. Civilian adoption of parking technology	4. Lifestyle services
	5. The level of parking technology implementation	5. Media
● Government Adoption (3)	● Traffic Management (3)	● E-payments (6)	● Green Buildings (4)
1. National digital infrastructure indices	1. Congestion levels	1. Percentage of the population that is in favour of a cashless society	1. Number of certified green buildings
2. Digital economy score	2. Time spent in traffic during a commute	2. Percentage of the population that has been cashless since the beginning of the pandemic	2. Building activities
3. Development of eGovernment services	3. Dissatisfaction due to long commute times	3. Number of cashless retail transactions per 1000 adults	3. Activities per square foot
		4. Credit card ownership	4. Percentage of total buildings certified as green
		5. Debit card ownership
		6. Percentage of the population that paid bills or bought something online in the past year
● Healthcare innovation (3)	● Clean Transport (3)	● Internet Connectivity (4)	● Waste Management (3)
1. Healthcare quality and access index	1. Electric cars per capita and new electric car sales	1. Median download and upload speeds	1. Waste generated per capita
2. The number of startups in the healthcare sector in each city, both in absolute terms and on a per population basis	2. Electric car charging stations per capita	2. 5G deployment and government efforts to promote 5G	2. Waste collection coverage
3. Number of app downloads and ranking in the healthcare and medical categories, excluding reference and utility apps	3. CO₂ emissions	3. 5G availability in major cities	3. The recycling rate in each country
		4. Number of 5G providers per city
● Teach Education (2)			● Climate Response (5)
1. Highly ranked universities for computer science degrees			1. Estimated percentage increase in greenhouse gas emissions
2. Highly ranked universities for engineering degrees			2. Total CO₂ emissions from fuel combustion
			3. Expenditure on environment protection
			4. Change in CO₂ emissions per capita over time
			5. Number of climate laws, policies and targets in place

Digital life refers to the prevalence of world-class technology, educational facilities and healthcare innovation systems present, and the amount of technology that has been adopted by a city on an individual and governmental level. Mobility innovation refers to the quality of parking innovation, traffic management and how green (environment friendly) the transportation is. Business technology infrastructure of each city include business innovation, the prevalence of e-Payments and the overall Internet connectivity. Sustainability refers to each city's environmental footprint. It includes responses to climate change and the handling of overall waste management, the number of green buildings and the usage of green energy.

Cities are separated into different groups, according to the population size. Large cities are those with populations 3+ million people. Medium-sized cities are those with populations between 600,000 and 3 million. Finally, small cities are those with populations between 50,000 and 600,000 people. Over 1000+ cities are evaluated by CFI.

Similar to IESE CIMI, EasyPark CFI computes scores based on counts of physical entities and not through residents' survey. Cities that perform well in the 4 criteria will be ranked higher than those who have not. Table 9 shows the city rankings for years 2017, 2019 and 2021. As shown, London, New York and San Francisco are the top 3 cities, followed by Singapore, Berlin, and Rotterdam. However, the past two earlier rankings are significantly different. London and New York were never in the top 10 for 2017 and 2019. Also, Paris has never been ranked among the top 10.

TABLE 9. The top 10 rankings of global big cities made by EasyPark Group

There exist great fluctuations in CFI rankings. For example, Singapore was ranked 2^nd in 2017 but dropped to 9^th in 2019 and back to 4^th in 2021. This indicates signs of instability in the rankings. This can be attributed to its criteria and indicators. There are only 4 criteria but 50 indicators. For medium-sized cities (population 600,000–3 million), the rankings for 2021 are 1. Copenhagen, 2. Stockholm, 3. Oslo, 4. Amsterdam, 5. Zurich, 6. Gothenburg, 7. Helsinki, 8. Boston, 9. Utretcht, and 10. Edinburgh.

2.5 Mori-Foundation Global Power City Index (GPCI)

Started in 2008, Global Power City Index (GPCI) [6] has ranked global cities according to 6 criteria, namely (1) economy, (2) R&D, (3) cultural interaction, (4) livability, (5) environment, and (6) accessibility. Each criterion is further broken down into indicators. A total of 70 indicators are used, and the average score for each indicator within a criterion are combined to compute a city's function-specific rankings, which are then totalled to determine its comprehensive ranking. Table 10 shows the criteria and set of indicators used.

TABLE 10. Six criteria and 70 indicators are used in Mori-Foundation's GPCI. [6]

1. Economy	2. R&D	3. Cultural interaction
1. Nominal GDP	1. Number of researchers	1. Number of international conferences
2. GDP per capita	2. World's top universities	2. Number of cultural events
3. GDP Growth rate	3. Research and development expenditure	3. Cultural content export value
4. Economic Freedom	4. Number of international students	4. Art market environment
5. Stock market capitalization	5. Academic performance	5. Tourist Attractions
6. World's top 500 companies	6. Number of patents	6. Proximity to world heritage sites
7. Total employment	7. Winners of prizes in science and technology	7. Nightlife options
8. Employees in business support services	8. Number of startups	8. Number of theatres
9. Wage level		9. Number of museums
10. Availability of skilled human resources		10. Number of stadiums
11. Variety of workplace options		11. Number of hotel rooms
12. Corporate tax rate		12. Number of luxury hotel rooms
13. Political, economic and business risk		13. Attractiveness of shopping options
		14. Attractiveness of dining options
		15. Number of foreign residents
		16. Number of foreign visitors

4. Livability	5. Environment	6. Accessibility
1. Total unemployment rate	1. Commitment to climate Action	1. Cities with direct international Flights
2. Total working hours	2. Renewable energy rate	2. International Freight flows
3. Workstyle Flexibility	3. Waste recycle rate	3. Number of air passengers
4. Housing rent	4. CO₂ emissions per capita	4. Number of Arrivals and departures at the Airport
5. Price level	5. Air quality	5. Station density
6. Number of murders	6. Comfort level of temperature	6. Public transportation use
7. Economic risk of natural disaster	7. Water quality	7. Travel time to Airports
8. Life expectancy	8. Urban greenery	8. Commuting time
9. Social Freedom and equality	9. Satisfaction with urban cleanliness	9. Traffic congestion
10. Risk to mental health		10. Ease of mobility by taxi or bicycle
11. Number of medical doctors
12. ICT readiness
13. Number of retail shops
14. Number of restaurants

By economy, GPCI refers to market size, attractiveness, economic vitality, human capital, and ease of doing business. For R&D, GPCI refers to academic resources, research environment and innovation. For cultural interaction, it refers to tourism, cultural activities and international interactions. For livability, it refers to cost of living, ease of living, working environment, security and safety, and well-being. For environment, it includes sustainability, air and water quality, and urban greenness. Finally, for accessibility, it refers to transportation (air and land) and traffic congestion.

As shown in Table 11, GPCI has been ranking cities since 2008. New York, London, Paris, Tokyo and Vienna were the top 5 cities in 2008. However, from 2009 to 2011, the rankings for the 5^th place had changed to Singapore instead of Vienna. The top 4 places remain unchanged. Change in the first place happened from 2012–2015, where London became the top city, followed by New York, Paris, Tokyo and Singapore. Finally, from 2016–2020, the rankings remained the change except the top 3^rd and 4^th places, where Tokyo is now third and Paris is fourth. Overall, one can see that from 2009–2020, the top 5 cities have essentially stayed in the top 5 positions, with London and New York constantly within the top 3 positions while Singapore has constantly stayed at the 5^th place.

TABLE 11. GPCI cities top 5 ranking from 2008–2020

Table 12 shows the spectrum of cities from top 6th to 10^th places over a period of 12 years. As can be seen, the commonly selected cities are Seoul, Amsterdam, Hong Kong, Berlin, and Sydney. Frankfurt, Vienna, Shanghai, and Zurich are less frequently selected over the years.

TABLE 12. GPCI city rankings of top 6–10 places from 2009–2020

Ranking/Year	6	7	8	9	10
2020	Amsterdam	Berlin	Seoul	Hong Kong	Shanghai
2019	Amsterdam	Seoul	Berlin	Hong Kong	Sydney
2018	Amsterdam	Seoul	Berlin	Hong Kong	Sydney
2017	Seoul	Amsterdam	Berlin	Hong Kong	Sydney
2016	Seoul	Hong Kong	Amsterdam	Berlin	Vienna
2015	Seoul	Hong Kong	Berlin	Amsterdam	Vienna
2014	Seoul	Amsterdam	Berlin	Hong Kong	Vienna
2013	Seoul	Amsterdam	Berlin	Vienna	Frankfurt
2012	Seoul	Amsterdam	Berlin	Hong Kong	Vienna
2011	Berlin	Seoul	Hong Kong	Amsterdam	Frankfurt
2010	Berlin	Amsterdam	Seoul	Hong Kong	Sydney
2009	Berlin	Vienna	Amsterdam	Zurich	Hong Kong

2.6 The SECI index by SmartEcoCity Ltd.

SmartEcoCity is a private organisation that analyses global and Asian cities. Its smart ecocity index (SECI) [15] evaluation is based on 7 categories: (1) transport and mobility, (2) sustainability, (3) governance, (4) innovation economy, (5) digitalisation, (6) living standard, and (7) experts' perception. SECI performed ranking of world cities based on smart, eco, and city criteria, which are explained below.

Smart (Equity): Improving the quality of life for citizens, social inclusion, public access, balanced development for all, making the city more attractive and fairer.
Eco (Environment): Reducing the environmental impact for better livability, sustainable city operations and activities, protecting the environment with minimal usage of energy, mobility, and water resources.
City (Economy): Involving citizens in bottom-up co-creation of growth initiatives, city-led government (instead of technology companies), clear vision, open innovation, resiliency plan to minimise impact of natural disasters, crime, virus pandemic, accidents and pollution.

Each criterion has a different weightage; transport is highest at 22.5%, followed by digitalisation (17.5%), governance (15%), sustainability (12.5%), living standard (10%), cybersecurity (7.5%), innovation economy (5%) and finally experts' perception (10%). The final score is the summation of all criteria scores. The 2018 global cities ranking is shown in Table 13.

TABLE 13. SECI 2018 ranking of global cities according to smartness, eco-friendly, and city performance

Surprisingly, the SmartEcoCity World Index has New York as top, which is similar to the Kearney GCI index. London was somehow missing from its top 10 rankings for 2018. Paris was ranked third, similar to other indexes. Singapore was placed on par with Paris, and the ranking is followed by Cleveland, Barcelona, Dubai, Berlin, Vienna, and Shanghai. Since there were a lot of cities with the same score, smartness and eco-friendliness precede those of others that have a lower score.

Note that since 2018, SmartEcoCity has not released any new reports or rankings. From its website, it has moved to focus more on Asian cities [15].

3 COMPARISONS OF INDEXES, CRITERIA, INDICATORS AND RANKINGS

It is important to do comparisons, as each smart city index creator claims that his/her index is the most appropriate, useful, and accurate. In this section, the six indexes are compared in terms of:

(a)
popularity,
(b)
evaluation criteria and indicators,
(c)
methodologies used and
(d)
cities' ranking.

3.1 Popularity comparisons

Before diving into detailed comparisons, the popularity of each of the six indexes are first examined using Google Search. As shown in Table 14, representative keywords are used to search for each index on the Internet. EasyPark Cities of the Future (CFI) Index yields the highest hits at 636,000, followed by Kearney Global Cities Index at 521,000, IESE Cities in Motion Index at 37,400 hits, and Mori-foundation GPCI at 12,700 hits. Finally, IMD-SUTD Smart City Index and SmartEcoCity SECI index have hits of 5460 and 5350, respectively. Based on this, IMD-SUTD and SmartEcoCity indexes are less frequently sought and cited on the Internet.

TABLE 14. Popularity comparisons: Google Search counts using keywords for the 6 smart city indexes

Keywords	Google Search hits (as of 11 Nov 2021)
EasyPark cities of the future index (CFI)	636,000
Kearney global cities index (GCI)	521,000
IESE cities in motion index (CIMI)	37,400
Global power city index (GPCI)	12,700
IMD-SUTD smart city index (I-SCI)	5460
SmartEcoCity index (SECI)	4640

While web search generates how frequently an index is sought on the Internet, it does not reveal which index is more authoritative than the others. Also, popularity does not imply universal acceptance. Hence, it remains to be seen which index will be more widely used and accepted in the future. Future work should include survey with world governments to understand which indexes are used or consulted and which are not.

3.2 Comparisons of evaluation criteria

Each index is created by different organisations and at different times. Hence, it is useful to compare their characteristics, allowing a better understanding of their commonalities and differences. As shown in Table 15, GPCI is one of the earliest indexes in existence, followed by GCI, IESE CIMI, SECI, and I-SCI. Evaluation criteria are used to quantitatively measure the performance of smart cities.

TABLE 15. General Comparisons of the six indexes. GCI 2008 and 2009 reports are not publicly available

	Indexes	Creator	Year started	Number of criteria	Remarks on acceptance and usage
1	IMD-SUTD smart city index	IMD school of business (Switzerland) and SUTD (Singapore)	2019	5	Created jointly by two universities
2	AT Kearney Global cities index (GCI)	AT Kearney Inc.	2008	5	Created by AT Kearney, a consulting management firm and GCI has been around for over 10 years. Its GCI is regarded as one of the oldest
3	IESE cities in motion (CIMI)	IESE school of business, university of Navarra (Spain)	2014	9	Created by a university business school
4	Cities of the future index (CFI)	Easypark Group Ltd.	2021	4	Easypark Group is a company involved in transportation business in Sweden
5	Global power city index (GPCI)	Mori-foundation of Japan	2008	6	Created by institute of urban studies, Mori-foundation of Japan. Its city ranking is among the oldest
6	SmartEcoCity index (SECI)	SEC Ltd.	2018	7	SEC Ltd. is a privately-owned consultancy company based in Beijing. Its index is less well known

Among the six indexes, SECI and CIMI use a higher number of evaluation criteria as compared to others. Note that criteria are grouping terms. Within each criterion, there are specific parameters (or commonly called indicators) to be measured and scored. I-SCI and CIMI are created by academic institutions while CFI, GCI and SmartEcoCity are created by industries. Only GPCI is created by a foundation. To date, there is no government entity that has created its own smart city index, neither has the ITU. Regardless of the origin of creators, all indexes evaluate cities based on a set of criteria and create a final score to rank cities.

As shown in Table 16, we compare in detail the evaluation criteria used by the six indexes. Since each index uses their own criteria, it is important to know which are common, essential and important. The various criteria are grouped into 8 types, namely (1) health, (2) transport, (3) living (people), (4) economy, (5) environment, (6) governance, (7) sustainability, and (8) digitalisation.

TABLE 16. Comparisons on the different evaluation criteria used by the six indexes (‘X’ means included)

IMD-SUTD I-SCI has 5 criteria: health and safety, mobility, activities, opportunities and governance. The use of criteria such as ‘activities’ and ‘opportunities’ may not be easily understood. These are very broad terms. Activities, in their perspective, refer to how easy it was for people to seek and enjoy entertainment and relaxation. For this, I have included it as part of ‘living’. Opportunities, however, refers to schooling and work opportunities. Hence, this is related to business and economy, which is why ‘opportunities’ have been marked under ‘economy’, as shown in Table 16. Nonetheless, I-SCI does not include sustainability, digitalisation, and environment.

AT Kearney GCI also has 5 criteria: business activity, human capital, information exchange, cultural experience, and political engagement. It uses the criterion ‘human capital’, which generally refers to human talent and assets. The assets being the experiences and skills the talent can bring to an organisation. Hence, the inclusion of human capital seems to imply that the larger the number of talents in a city, the better it is. This obviously is not entirely true. A city also needs diversity in people. Hence, to evaluate a smart city based on the number of highly capable talents do not quite reflect how smart a city is. GCI also uses the criterion ‘cultural experience’ to evaluate a city. Experiences are very much tied to how a person feel, and hence there is a personal preference and emotional aspect of it, which is hard to quantify. Measuring experiences is subjective, not objective. In addition, different countries and cities have different cultures, and hence it seems inappropriate to expect people to like cross-cultures. Finally, GCI also uses ‘political engagement’. This criterion is not clearly defined by AT Kearny. Co-incidentally, AT Kearny also uses this same criterion for their Globalisation Index [7]. Hence, the appropriateness of this criterion is questionable (unless it refers to governance but political engagement refers to both sides, i.e. the citizens and the government). Hence, in these aspects, GCI uses broadly defined criteria for its index. GCI did not cover health, transport, living and most importantly sustainability.

IESE CIMI has the highest number of criteria among all five indexes. Its 9 criteria are governance, urban planning, technology, environment, international projection, social cohesion, human capital, mobility/transportation, and economy. Technology and economy are the more generally mentioned criteria. However, there are 4 less frequently used and understood criteria. The first is urban planning. Why is urban planning a criterion and how could one go about measuring urban planning? Urban planning is a process, not an outcome and for smart city indexes, one should be measuring outcome. The next criterion is international projection. This refers to a city's global reputation and its global outreach. Often, this is tied to the city ‘branding’, tourism, marketing etc. However, why is ‘branding’ related to how smart or well performed a city is? Hence, this criterion is debatable. Next is the social cohesion criterion, which refers to the level of intermix or coexistence among people with differences in ethnicity, job nature, age, income etc. Again, why is this important or tied closely to how well a smart city will perform? This is a city people composition issue and is not tied to the outcome of a smart city. Finally, CIMI uses the human capital criterion, which is also used by GCI. However, as mentioned earlier, the quality of people or talents in a city does not directly reflect its performance. Hence, CIMI lacks sustainability, health, and living criteria.

EasyPark CFI uses only 4 criteria to derive its index. They are digital life, mobility innovation, business technology infrastructures and environmental sustainability. The criterion digital life does not refer to quality of the lives of people. Rather, it refers to the use of digital technology in people's daily lives. Hence, this is part of digitalisation. Next, the criterion mobility innovation is a mixture of transport and digital innovation since it covers traffic management issues and the use of digital technologies for transport. Hence, this criterion is included under both transport and digitalisation. The third criterion business technology infrastructure refers to business technology and Internet connectivity (which is digitalisation). Regrettably, it does not refer to the economy of a city. Hence, this criterion is grouped under digitalisation. The final criterion is environmental sustainability, which refers to staying green and reducing waste. Hence, this criterion is classified under both environment and sustainability. As can be seen, CFI does not include economy, health and governance.

Mori-foundation GPCI uses 6 criteria to evaluate global cities. They are 1) economy, (2) R&D, (3) cultural interaction, (4) livability, (5) environment, and (6) accessibility. Economy is a commonly used and accepted criterion in other indexes. As for R&D, it includes innovation, which is also part of digitalisation and technology. As for cultural interaction, it is unclear why this is important. As for livability, this criterion is essential as it concerns lives of residents. Environment here includes greenness and sustainability. Hence, it has factored sustainability into the environment criterion. Finally, accessibility here refers to transport. Table 16 reflects the criteria present in GPCI. However, GPCI lacks health and governance.

Finally, SmartEcoCity SECI introduces 7 criteria for a smart city. They are transport and mobility, sustainability, governance, economy, digitalisation, living standard, and experts' perception. The 2 criteria that are different from other indexes are living standard and experts' perception. By living standard, SECI defines it as the quality of life of people. By expert perception it refers to how smart city experts view the overall wellness of a smart city. While quality of life criteria makes good sense, experts' perception is dependent on the number and quality of experts. This again is a subjective criterion since SECI does not list or name these experts nor outline the credential requirements of these experts. Hence, SECI lacks the health criteria.

Overall, as shown in Table 16, none of the indexes include all 8 criteria. Only I-SCI specifically include health. Most indexes agree that transport is an essential criterion (except GCI). Only I-SCI, SECI and GPCI specifically considers people/living as important. All indexes consider economy (except CFI) and digitalisation (except I-SCI) as requirements. Only CIMI, GPCI, and CFI specifically consider environment and only CFI, GPCI, and SECI consider sustainability. Finally, all indexes (except GCI, GPCI and CFI) consider governance as a required criterion in evaluating smart cities. Overall, CIMI uses the largest number of evaluation criteria of 9, but urban planning, social cohesion, human capital and international projection are not commonly found among other indexes. This is followed by SECI with 7 criteria, but it lacks the essential health criterion.

3.3 Comparisons of methodologies used

All the six indexes use a set of criteria followed by a long list of indicators to evaluate global cities. The number and type of indicators used are different for each criterion while others have commonalities (see Table 17).

TABLE 17. Comparisons of the Methodologies, number of criteria and indicators used by the six Indexes

	Indexes	Methodology used	Remarks
1	IMD-SUTD smart city index (I-SCI)	Final score depends on the performance of previous 2 years (i.e. ratio of 3:2:1)	Scoring based on 5 criteria with 39 indicators. Each criterion is scored based on questions stated in a survey and completed by residents. Past 2 years of performance affects the final score
2	AT Kearney Global cities index (GCI)	Final score is obtained by adding the weighted scores from each of the 5 criteria	Scoring based on 5 criteria with 29 indicators. Each criteria carries different weightage. Scores are not based on survey but on actual physical entity count
3	IESE cities in motion (CIMI)	Final score is derived from scores obtained for each indicator within each criterion	Numeric scores are given to 101 indicators found in the 9 criteria used. The index does not rely on surveys
4	EasyPark cities of the future index (CFI)	Final score is derived from scores obtained for each indicator within each criterion	Numeric scores are given to 50 indicators found in the 4 criteria used. The index does not rely on surveys
5	MORI Global power city index (GPCI)	Final score is derived from scores obtained for each indicator within each criterion	Numeric scores are given to 70 indicators found in the 6 criteria used. The index does not rely on surveys
6	SmartEcoCity index (SECI)	Final score is obtained by adding the weighted scores from each of the 7 criteria	Numeric scores are given to the 7 criteria: transport, sustainability, governance, economy, digitalisation, living, cyber security, and experts' perception. Note that experts' perception is a form of survey

In some indicators, actual physical count is used to derive the score (example, the number of gas stations in a city). Some rely on available data from city agencies. SECI, for example, relies on experts' perception to derive scores. IMD-SUTD SCI also uses surveys to gather scores, but their survey population is rather limited (in the order of hundreds). Also, it is unclear what and how questions are created for residents to answer. While some have used simple summation of each criterion score to yield the final score to rank cities, IMD-SUTD uses a city's past 2 years performance (ratio of 3:2:1) to yield final score for ranking. This ratio will result in cities who had been poorly ranked in the last 2 years to not be able to move significantly up in the ranking, despite having done extremely well in the current year. All the methodologies used are created by the individual index organisations and are not vetted upon by third parties. Hence, it is insufficient to conclude if one methodology is more superior or more universally accepted than the others.

3.4 City ranking comparisons

Each year, each index ranks cities based on their established criteria. Hence, it is useful to examine if their rankings are similar and if not, how different. In our comparisons, we would like to look into (a) appropriateness and (b) accuracy of these indexes so as to gain common grounds and insights that could be universally accepted among all indexing creators.

As shown from Table 18, GCI CIMI, GPCI and CFI all point to 2 cities in common as top cities, namely London and New York. GCI and CIMI both have Paris as the top third city while I-SCI has chosen Oslo, CFI has chosen San Francisco and GPCI has chosen Tokyo as third. GCI and CIMI both have Tokyo as the top fourth city while I-SCI has chosen Taipei, CFI has chosen Singapore and GPCI has chosen Paris as fourth. Finally, all indexes have different cities for the fifth place. I-SCI has chosen Lausanne, while GCI has chosen Los Angeles, CIMI has chosen Reykjavik, CFI has chosen Berlin, and GCPI has chosen Singapore for the fifth place.

TABLE 18. Comparisons on city rankings by the six indexes. London and New York have appeared top among the four indexes (GCI, CIMI, CFI, and GPCI)

It is unknown why San Francisco is being shortlisted as top three in CFI despite not being selected in other indexes. Finally, the I-SCI ranking has clearly deviated from the other 5 rankings. Singapore, Zurich and Oslo were never listed among the top 3 for GCI, CIMI, GPCI and CFI rankings. Hence, the I-SCI ranking has far deviated from the other rankings, raising doubts about the accuracy and reliability of its ranking. Since SECI only ranks global cities in 2018 and not thereafter, it is not appropriate to compare it with other city indexes.

4 SUGGESTIONS AND FUTURE WORK

Indexes, be it created by universities or industries or consortiums or foundations, must be widely accepted and recognised by city governments and the community. Without this universal acceptance status, these indexes tend to have a limited impact and will still receive scepticism on neutrality, accuracy and reliability. City government needs to judge the performance of its city and big countries with multiple cities need to collectively judge the performance of all its cities. This is a critical and non-trivial task and a universally accepted approach of evaluation and ranking is needed.

Since late 2019, many global cities have been ‘invaded’ by COVID19. These include top cities like London, Paris, and New York. In fact, the fatality and severity of these cities are alarming. As of November 2021, London has over 1,192,075 cases (current and past) and over 16,059 deaths. New York City has a total of 2,658,501 cases and 57,186 deaths while Paris city has 27,527 cases and 4821 deaths. Coincidentally, London and Paris are both capital cities. And the countries with top 3 deaths are USA, Brazil, and India. It is widely known that the epic-centre of the USA COVID19 crisis is in New York City. Hence, in this aspect, for 2020 and 2021, New York City is far from top given it performed very badly during the COVID19 crisis. Hence, current smart cities are not well equipped to deal with sudden pandemics.

Health attack (example virus) can bring down a city's economy, cripple its transport, digitalisation, living etc. Hence, such an event will bring down most cities' performance indexes. This chain of events will dramatically scale down the economy and quality of life of city residents. The confinement and isolation strategy executed by some countries (China, UK etc.,) have brought pains and complaints from city residents. This brings up the question on what is the right formula and index for smart cities? What proportion should health weigh against economy, transport etc.,? Being a top smart city but defenceless against a COVID or virus attack is unacceptable. A smart city's set of criteria must, therefore, include health.

NEC Japan has introduced a Safe City Index [16]. They examined 5 aspects: (1) digital security, (2) health security, (3) personal security, (4) environmental security, and (5) infrastructure security. While existing smart city indexes have included criteria such as health, transport, living, economy, sustainability, environment, technology and governance, the safety aspects have largely been undermined. After the occurrence of COVID19, the author suggests that the following considerations are necessary:

R: RESILIENCE of a city against attacks or crisis
A: ADAPTABILITY in times of attacks or crisis
R: RECOVERY from the traumatic event

There are 2 possible approaches to include RAR (resilience, adaptability and recovery). One is to include RAR within existing criteria of health, transport, living, economy, sustainability, environment, technology, and governance, since the onset of a traumatic event can impact all the existing criteria. An alternative is to create a new criterion called RAR to specifically evaluate and measure a city's resilience, adaptability and recovery ability against attacks and disasters. Future work should include:

(1)
harmonisation of smart city indexing bodies,
(2)
convergence to a set of widely agreeable criteria and indicators,
(3)
openness in the availability of city data for sharing and learning,
(4)
wider dissemination of cities' rankings, and
(5)
using the ranking to improve a city's smartness and the quality of life of residents.

5 CONCLUSION

Smart cities have been in development in many countries throughout the world for over a decade now. However, there exists no universal and widely accepted index to rank global cities accurately and reliably. Currently, the existence of multiple indexes and rankings from different sources can add to confusion and tedious readings, with no convergence in sight. In this paper, 6 existing indexes originated from major organisations are discussed in detail, especially on their chosen criteria, indicators, methodologies used, and their cities' rankings over the last decade. In-depth comparisons are made among these 6 indexes, highlighting their commonalities, differences, comprehensiveness and shortcomings. Key and essential criteria found in these indexes are health, living, transport, economy, environment, technology, governance, and sustainability. Consistency in city rankings exists, with London, Paris and New York being ranked the top 3 cities. This investigation has pointed out that using past few years of ranking outcomes to evaluate a city current year ranking can put a city at a disadvantage, especially if the city has not performed well in the last few years. This paper has also revealed the need for global attention to participate and converge onto a commonly and universally accepted smart city index and criteria. Similar to the Olympics games, where players are ranked accordingly to specific rules and measures, global cities need to be ranked to reflect their true status, abilities, weaknesses and offerings. The final outcome of such a ranking is not for prestige or marketing purposes but rather to accurately reflect which city has a higher quality of life and a greener environment for its residents while at the same time achieving sustainability. Policy makers and government can then use these findings to improve on their cities. Rankings allow cities to learn from each other and make progress. Finally, in addition to the key essential criteria identified by this paper, RAR (resilience, adaptation and recovery) is recommended as a new additional metric to equip world governments with the ability to measure vulnerability, assess readiness from external attacks, and provide means to deal with pandemics, natural disasters, sudden hazards and being able to quickly recover from them.

CONFLICT OF INTEREST

The author declares that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported.

Smart city indexes, criteria, indicators and rankings: An in-depth investigation and analysis

Abstract

1 INTRODUCTION

2 CURRENT INDEXES