“Marketing research in the context of trust in the public sector: A case of the digital environment”

Trust in public services is a driving force of socio-economic development. It ensures effective dialogue between citizens and government and becomes especially relevant in the digitalization. The lack of trust in the public sector can make reforms ineffective and the achievement of the goals of the Ministry of Digital Transformation within the framework of the State Strategy for Regional Development of Ukraine until 2027 in question. For this reason, marketing tools in public services should be directed toward achieving greater trust in those services and the government. This paper analyzes the current research on public sector marketing and its role in building trust as a foundation for the country’s digital development. Implementing multi-level bibliometric (Scopus tools), network (VOSviewer), and comparative (Google Trends) analysis, this study traces the development of marketing research on the process of public services delivery transformation from traditional to digital. 922 studies published between 1968 and 2022 were analyzed. The results show that public sector marketing is a multi-disciplinary field of scientific research that is actively developing. Cluster analysis demonstrated that its modernization and the relationship between marketing in services and consumer behavior are the smallest and newest spheres of research. Researchers consider relationship marketing the principal mechanism for building trust in the public sector. This study found little research on the impact of marketing tools on consumers’ trust in public services. The comparative analysis confirmed the hypothesis of the need to change marketing tools due to the massive shift from offline to online services.


INTRODUCTION
The current state of the public administration system is characterized by an increased emphasis on finding new and effective marketing strategies and tools.This reflects the rapid digitalization of society and the public sector.First, the digitalization of the public sector is convenient for citizens and a synonym for anti-corruption.Second, the digital transformation process ensures equal access for all Ukrainians to the country's information and service resources.Digitalization has become a top priority of Ukraine's State Strategy for Regional Development until 2027.The document also foresees the introduction of an electronic document reception system and the possibility of requesting public services through online services and electronic queues.In these conditions, consumers' trust in public services is the key to effective interaction between the population and public authorities.Thus, meeting the needs of consumers reflects the efficiency and appropriateness of the structure of government agencies.
According to the Rating group data, the state-in-a-smartphone program, implemented by the Ministry of Digital Transformation and other ministries and international organizations, is rated the highest by Ukrainians among the main areas of government activity; 64% of respondents trust it (Rating group, 2021).In addition, when assessing changes in the implementation of digital technologies at the state level, 49% of respondents felt an improvement in this area (Rating group, 2021).However, almost half of the sample is unsatisfied with digital government services or do not use them.The lack of public trust in public services hampers the promotion of innovative ideas and limits the potential of administrative reforms.Changing consumer behavior with state-of-the-art devices and technologies creates new challenges to building trust.The shift from offline public services to online public services, which, according to the Minister of Digital Transformation Mykhailo Fedorov, will add 10-12% to the country's GDP, requires increased digital awareness (Government Portal, 2021).The existing marketing tools of the public sector cannot fully satisfy the needs of ensuring trust in public services and hinder the digital transformation.Such circumstances require the state's implementation of new modern marketing tools and approaches to increase trust in the public sector.However, their effectiveness will depend on the availability of academic support in theoretical and methodological foundations and empirical research.

LITERATURE REVIEW
There is a large volume of published studies describing the role of digitalization.Different theories exist in the literature regarding the positive and negative consequences of digital transformation in society (Martins et Kwilinski et al., 2020).Some of these studies were directed at investigating the differential impact of digitalization on banking products and services from a customer-oriented perspective (Prokopenko et al., 2022), while others discussed digital shifts in the financial industry in general (Kolodiziev et al., 2021;Volosovych et al., 2021;Kolodiziev et al., 2022).At the other end of the spectrum of academic research, there is a discussion about the link between the digital divide and the level of economic development of regions (Deineko et al., 2022;Melnyk et al., 2022) or country macroeconomic stability (Petroye et al., 2020;Tiutiunyk et al., 2021;Wang et al., 2022).Other researchers, however, who have looked at macroeconomic stability, despite a critical role in the technological evolution of Industry 4.0, have identified other determinants.They include social (Didenko et al., 2020), economic (Leonov et al., 2014;Bilan et al., 2020), behavioral (Didenko et al., 2020), and healthcare aspects (Kuznyetsova et al., 2021).Yarovenko et al. (2021) highlighted that changes in information technology could lead not only to macroeconomic developments but also to risks.Kobushko et al. (2021) expanded their perspective by stating that technological developments, similar to data mining, bifurcation, gravitational and intellectual data analysis, could be used to reduce the risks associated with money laundering.
A great deal has been written on public sector marketing.These studies have been devoted to the development trends of public service marketing in European democracies, transformations in strategy and tactics, and changes in marketing tools in digitalization.Public applications and limits of public marketing within this framework for the four classical marketing instruments (product development/improvement, price, promotion, and place) have been established (Kaplan & Haenlein, 2009).In-depth research has shown that public marketing (that is, the application of marketing concepts and tools to public administration) has already been a reality in various countries (Kaplan et al., 2007).Florescu et al. (2003) have mainly been interested in how marketing processes and tools can be used to meet the public interest.Others have highlighted the relevance of a custom blend of the four Ps (product (or service), place, price, and promotion) as well as other marketing techniques to transform communications with public service consumers (Serrat, 2017;Kaplan & Haenlein, 2009).Lamb (1987) and Yula et al. (2020) have attempted to draw fine differences in the marketing strategies of private firms and public organizations, as well as the solution to marketing problems that create these differences.Much of the available literature on govern-mental marketing deals with the use of the 4C and 7P concepts in the public sector (Scheibe, 2013).However, Kollet (2019) is much more concerned with the marketing behavior of public authorities, which forms the public organization's image and allows public services to adapt to the needs of the target market.
Given the latest trends in scientific research, the use of bibliometric analysis tools (VOSViewer, Scopus and Web of Science instruments, Publish or Perish, and Google Trends) has become quite popular.It forms and provides a theoretical basis for determining the main trends in developing the studied concepts (Khomenko et  It should be noted that a bibliometric analysis of public sector marketing was conducted earlier (Matos et al., 2020).This study focused on finding marketing mechanisms in four public sector groups: education, health care, social economy, and urban policy.However, the relationship between the development of marketing tools and trust in the conditions of global digitalization still needs to be identified.Thus, apart from Matos et al. (2020), research related to the theoretical background of public sector marketing is underrepresented in academic circles.Moreover, previous studies do not distinguish the connection between trust in the public sector and the tools to ensure it.Therefore, studying the scientific landscape regarding these goals, their synergistic effects in light of the challenges of global digitalization, and the prospects for implementing government interventions in public services is an important task that can be solved based on bibliometric analysis tools.
This paper aims to examine the current state of research on public sector marketing and its role in building trust in the public sector as a foundation for the country's digital development.

METHODOLOGY
Bibliometric tools have been used extensively in the past to study patterns and features of scientific works already published in the marketing area.Rowley and Slack (2004), using deduction-based analytical methods, offered a structured method-ology for scanning academic literature.Adopted similar approach, this study used a five-step methodology for data collection and analysis to identify and argue that trust in the public sector and digitalization are contemporary trends in marketing research.
Based on a comprehensive review of the literature, the following combination of keywords was chosen for data collection and the initial search: "marketing AND public AND sector.".In the scientific literature, the main search word "public sector" is equated in meaning with "state", "stateowned", "government", and "public administration".But, despite being synonymous, they are different.The meaning of the word "public sector" is broader and includes all organizations and industries owned or controlled by the government (Cambridge Dictionary).Moreover, the phrase "public sector marketing" is used as a permanent expression.
The initial search result in the Scopus database showed a total of 4171 articles, conference papers, books, and chapters of books in the period from 1968 through 2022.Refinement of the search results took place by selecting all open-access publications; such studies can be freely read, downloaded, copied, distributed, printed, and used in education, significantly increasing the citation and FWCI rates (Field-Weighted citation impact).Refinement of the search results and discarding irrelevant search queries resulted in 922 unique papers.It should be noted that such a shortening did not lead to a reduction in the research period.Therefore, the analysis is conducted from the first comprehensive study in the field of public sector marketing and covers the period 1968-2022.
Since this study is also designed to determine how marketing methods and strategies in the public sector have changed with the advent of digitalization, it should use a technique that allows considering consumer trends in society, e.g., Google Trends.To search for keywords, the study focused on the methods of delivering public services to citizens.There are two ways of obtaining them today: digital (via an application or an Internet platform) and traditional (in centers for providing administrative services and other state institutions).That is why "Digital public service" AND "Traditional public service" were identified as key queries for comparative analysis.The maximum period covered by Google Trends is from 2004 to the date of the user's request.The study deliberately shortened the analyzed period to 2017-2022, as it wanted to demonstrate how consumer attitudes changed with the advent of digital transformation in the public sector.So, until 2017, citizens only showed interest in traditional public services.
In order to evaluate the productivity of the publications in the field of public sector marketing, the number of publications was analyzed according to the year and the field through the application of integrated Scopus tools.The second method used in the study was directed to measure publication influence and involved analysis of the number of citations, i.e., country citations measurements, countries co-authorship measurements, spatiotemporal measurements.To analyze the results in greater depth, the paper utilized a graphical mapping of the bibliographic material by applying the VOS viewer software version 1.6.10.In the identification of public interest patterns and comparative analysis, Google Trends was used.A description of each methodological tools, the specifics of their use for the current study, chosen keywords, and available periods for each instrument are shown in Table 1.
Deep bibliometrics includes defining key terms and relevant research areas and finding the most influential studies, authors, journals, and new research groups.That is why it is proposed to divide the analysis into the following stages: • selection of a key query "Marketing AND public AND sector" in the Scopus database for the initial search and clarification of the search results (publications that are All Open Access are included in the analysis); • use of built-in Scopus tools for initial analysis of documents published between 1968 and 2022; • importing information about publications from the Scopus database in CSV Excel format into the VosViewer program (922 academic studies); • primary analysis of 423 keywords through VOSviewer, manual exclusion of keywords from other fields of science, irrelevant and repeated terms from the list of keywords.35 keywords were selected for VOSviewer overlay visualization; • processing of received information through VOSviewer for cluster analysis, country citations, countries co-authorship, and spatiotemporal measurements (unit of analysis: all keywords); • content analysis of clusters and intercluster connections; • selection of keywords "Digital public service" AND "Traditional public service" and time period 2017-2022 for Google Trends.Comparative analysis, and identification of trends of public interest conducting.

Google Trends
Google product that analyses part of all Google Search web queries and other affiliated Google sites.The statistics are presented on a graphical basis.

RESULTS
In the largest abstract and citation database of peer-reviewed literature, Scopus, the relevant publications have been chosen according to the keywords "marketing AND public AND sector."The combination of keywords has brought to light a total of 922 academic studies in All Open Access published between 1968 and 2022.This study covered 179 authors, 163 journals, and 92 countries.
The initial analysis of documents provides statistical information and an overview of published scientific articles, conference materials, and books in a certain field of research.This stage of the analysis includes the determination of development stages of scientific interest in public services marketing and the industry structure analysis.Figure 1 shows the dynamics of the number of scientific publications on public sector marketing.The number of published studies has grown moderately since 1990, and in 2003, the first boom of scientific interest in this field took place.However, the research did not stop there; the trend line shows the increasing dynamics of the number of publications; in 2021, their number was 97.This indicator is twice as much as in 2017 and three times as much as in 2009.Thus, scientific interest in public sector marketing development takes place at a galloping pace.
Thus, based on the amplitude of Figure 1, the following stages of research development in the area of public sector marketing can be distinguished: • Stage I (1968-1991) -lack of scientific interest in the topic.
• Stage II (1991-2002) -the emergence of theoretical and practical interest in public sector marketing.Volatility in the number of scientific publications is characteristic of this stage.
For ten years, the number of published scientific studies ranged from 0 to 10. Public sector marketing applies to all spheres of state regulation, including the healthcare system, education, protection of citizens' rights, business and entrepreneurship, and others.Thus, the industry structure analysis can provide important information about the level of diversification of research into the marketing of public services (Figure 2).
Figure 2 shows that nearly 25.3% of all research is conducted in medicine and health.One of the most cited studies in this field is a publication on the secondary use of health data outside healthcare.Researchers suggest using such information for marketing research and analysis of information about the quality of public healthcare services (Safran et al., 2007).The second largest share (14.4%) of research is in the field of social sciences.
Influential studies are related to the use of official mass media as an element of the state's marketing strategy (Hays et al., 2013) and the development of marketing partnerships between the state and private sector (Buhalis, 2000).Business, management, and accounting rank third in the sectoral structure of public sector marketing research.With 8.1% of all research, such publications are related to management and marketing strategies of the public sector and related industries (Fornell et al., 1996;Leonidou et al., 2013).Natural, agricultural, and economic research obtained at most 8% for each branch in the overall structure of the number of publications.Thus, the initial analysis of public sector marketing documents by subject area demonstrates a significant diversification of research and confirms the hypothesis about the multidisciplinary nature of the studied concept.
In the Scopus database, the relevant publications have been chosen according to the keywords "marketing AND public AND sector."The combination of keywords has brought to light 922 scientific publications in this area.Using VOSviewer software calculations, 35 keywords were broken into 6 groups (Figure 3a).The largest cluster (red) comprises eight keywords related to customer satisfaction with public services: customer satisfaction, service quality, service marketing, government services, branding, brand equity, and loyalty.The green cluster comprises public sector marketing components (relationship marketing, internal marketing) and concepts needed to develop a gov-Source: Compiled by authors via Scopus in-built instruments.ernment marketing strategy (trust and innovation).
The blue cluster has six keywords that describe the state's marketing policy (local government, government, stakeholders, decision-making, and economic and social impact).The yellow cluster represents the government's marketing policy reform related to the development of the Internet, information technology, social media, and the overall digitization of the public sector.Finally, the purple cluster explores the communication process in marketing and the blue relationship between marketing in services and consumer behavior.
As shown in Figure 3b, public sector marketing uses the concept of relationship marketing, which links consumer trust with service quality, loyalty, and satisfaction of service consum-  For many years, a central theoretical question that dominated public services related to trust in public sector bodies.Van de Walle and Bouckaert (2003) considered public trust in government as the basis for public sector modernization.Thus, the efficiency of public administration has a particular impact on confidence in government because public distrust is often the consequence of the poor quality of public services.However, despite the importance of trust in public organizations' concept, there still needs to be more research on marketing tools for building a high level of trust in public institutions and their services.This reflects the complexity of the concept of trust (Mayer et al., 1995).This paper explores marketing tools to influence consumer trust in digital (online) and traditional (offline) public services.
A co-authorship geographic analysis (Figure 5) revealed that the centers of public sector marketing research and associated trust are the United Kingdom, the United States, Australia, and Canada.The largest cluster by co-authorship is the red cluster, which includes Canada, Denmark, China, Germany, Greece, Mexico, Norway, and Spain.Thus, scientists from these countries often worked together to research aspects of marketing in the public sector.
Territorial-geographical analysis of citations (Figure 6a) showed that the most cited are the works of scientists from the United States, the United Kingdom, and Australia, to a lesser extent.In addition, leading positions were also taken by Spain and Canada.Thanks to the spatio-temporal analysis (Figure 6b), we can conclude that the leading countries in citation were the first in public sector marketing research; later, research on this topic began in Germany, Canada, and Greece.The study of public sector marketing remains a new topic for Brazil, Portugal, Sweden, Switzerland, and China.
Taken together, these studies support the notion that marketing research in the public sector was developed in response to contemporary trends in the socio-economic environment and technology implementation.The evidence reviewed here suggests a pertinent role of marketing tools in public services for enhancing the greater trust in those services and the government.However, these   studies remain narrow to determine if there is any difference between the marketing tools used for traditional and digital public services.
As shown by the cluster and spatio-temporal analysis, the latest research in public sector marketing is focused on implementing digital technologies in public services.That is why to identify the main trends for the scientific development of public sector marketing, it is offered to consider a comparative analysis of the search queries "Digital public service" AND "Traditional public service" in Google Trends.Visualization of the dynamics of public interest in the proposed concepts is shown in Figure 7.
The comparative analysis was carried out over the last five years to demonstrate how consumer attitudes have transformed in the field of public affairs.As can be seen from the amplitude in Figure 7, until 2020, interest in traditional public services prevailed among public requests.Still, consumer preferences changed with the advent of the pandemic and general quarantine.As a result, interest in online services increased almost twice; they surpassed traditional public services in available dynamics.Thus, 2020-2021 can be called the period of digitization of the public sector.Although governments have been gradually implementing the transformation process for a long time, the turning point in the development of public services was the COVID-19 pandemic.That is why the public sector marketing trend is searching for new tools to deliver digital services effectively.

DISCUSSION
Prior studies highlighting the importance of marketing tools in the public sector have shown that a set of marketing processes and tools can be used to meet the public interest (Florescu et al., 2003).However, as mentioned in the literature review, most published articles on marketing at the governmental level deal with the use of the 4C and 7P concepts in the public sector (Kaplan & Haenlein, 2009).
The basis was Matos et al.'s (2020) study, which conducted a bibliometric analysis of public services marketing.However, the difference in results lies in the ultimate goal of the study.Matos et al.
(2020) provided an up-to-date outline of public sector marketing (education, health care, social economy, and urban policy).In this study, the ultimate goal is to recognize the theoretical connections between the development of public sector marketing tools and trust in the public sector in the context of global digitalization.These connections have not previously been described and can be used in further scientific discussions as a road map for building trust in the public sector through traditional and digital government services.
An interesting finding of the study was that the peak of scientific activity fell from 2017 to 2022, and most of these publications relate to the medical field and the healthcare system.This finding was confirmed by subject area analysis.This situation may be associated with the general popularity of marketing tools In addition, the results of the cluster analysis turned out to be unexpected.However, the digitization process has been going on for more than ten years, and the cluster describing the modernization of the sphere of public services to the population is one of the smallest.This state of research can become a problem for the development of public administration.In most countries, paper document circulation still works, services are provided offline, no government internet platforms, and the government ignores the possibilities of technology.This study supports evidence from previous observations (e.g., Lindgren et al., 2019;Kuhlmann & Bogumil, 2021), that indicates the lack of digital reforms of marketing strategies in the public sector may be due to an insufficient theoretical basis for their implementation and required skills for citizens and public officials.In addition, governments are afraid to implement new technologies in marketing public services due to the non-availability of trust.This fear is also well-founded, based on the results of cluster analysis of network connections.
The Ukrainian government is actively trying to implement digital technologies in the public services system.The Ministry of Digital Transformation aims to ensure the provision of 100% of all public services online by 2024, create Internet coverage for 95% of all highways and social facilities, and increase the share of IT companies in Ukraine to 10% of the GDP.This study supports evidence of Ukraine's State Strategy for Regional Development until 2027 and can become a theoretical basis for implementing and updating public sector marketing strategies.
This paper analyzes the readiness of the scientific community to create prerequisites for the progressive implementation of public sector marketing, studying its role in building trust in the government as a basis for the country's digital development.
For this purpose, a bibliometric analysis of the scientific literature on public sector marketing was conducted from 1968 to 2022.The study used several special methods and tools, including built-in Scopus tools, VosViewer software, and Google Trends.
The initial analysis of studies revealed five stages of the development of scientific interest in the marketing of public services, while the most scientific literature was published from 2017 to 2022.The industry structure analysis showed a significant diversification of research and confirmed the hypothesis about the multidisciplinary nature of public sector marketing.Bibliometric analysis of marketing research in the public sector has identified 6 clusters, two of which relate to the modernization of the sphere of public services and the relationship between marketing in services and consumer behavior.
This study revealed the scientific community's unpreparedness to develop and implement marketing tools to ensure trust in the public sector in the face of digitalization.However, trends analysis showed that the transition to online public services is inevitable.Therefore, developing marketing mechanisms and strategies is necessary for public administration.The findings reported here shed new light on public sector marketing and add to the rapidly expanding field of digital public services.Furthermore, the results of this study have several practical implications.Policymakers could use the theoretical basis in marketing strategy to enhance consumer trust in public services, and for researchers, this paper is a meaningful literature review of public sector marketing.

Figure 2 .
Figure 2. The initial analysis of documents by subject area ers and is part of the marketing strategy in the public sector.The time perspective (change from blue to yellow, where yellow is the most recent research and blue is the earliest research) presented in Figure 3c suggests that the emerging areas of public sector marketing research are customer loyalty.According to Figure 4, investigators have recently been studying the impact of digitization on public services.Several studies suggest that the digital transformation of the public sector is an essential step toward more citizen-and user-centric service delivery (Kuhlmann & Bogumil, 2021; Aswar et al., 2022).Consequently, it allows to delay paper forms, and repeated provision of information can be eliminated (Lolich & Timonen, 2022) through different marketing tools.Source: Based on VOSviewer analysis.

Figure 3 .
Figure 3. Graphic visualization of research on public service marketing c)

Figure 4 .Figure 5 .
Figure 4. Overlay visualization map of spatio-temporal measurement of research on public sector marketing according to the Scopus database
Source: Compiled by authors via Google Trends.