Introduction

Retail has been assuming increasing importance in academia as a result of the transformations caused by the emergence of new digital technologies that promise to change the way people related to consumption. New phenomena addressing channel strategy, consumer behavior, shopper experience, innovation, digital technologies, new operational processes, among others, providing new opportunities to researchers focused on initiating investigations in a brand new retail marketing area.

According to Juaneda-Ayensa et al. (2016), omnichannel is defined as "more than a configuration of channels design or technological systems," as a result of digital transformation experienced by the global retail market. The aim is providing perfect shopping experiences, free of barriers or operational friction presents in the most common shopping processes. This model is made possible by the merger of physical and digital channels through a complex integration of operational, technological, and logistical systems that is complemented by the availability of user-friendly applications for consumer interface (Rigby, 2011).

The theme omnichannel aroused attention to its exploration in this article because it is already present in business conferences, agendas of sectoral journals, i.e., publications to managers and professionals working in the retail sector and companies that have the final consumer as the primary objective.

The initial step was to select journals with a more significant impact in order to analyze the scientific production on omnichannel, and it was immediately verified that this is an emerging theme that lacks conceptual construction to achieve theoretical robustness. This study, therefore, proposes a broad investigation in the most significant impact publications with mapping what has most aroused interest to researchers in the approach to the omnichannel theme.

Web of Science and Scopus were databases used for investigation from the term omnichannel, in business, which has generated a formerly selection of about 115 publications, resulting in 80 papers after adjustments, analyzes through systematic review and quantitative content analysis.

The research in the selected publications reveals that the physical store remains the most significant reference for the retail activity. However, such physical stores will start interacting with more accessible and user-friendly digital technologies, such as smartphones, tablets, connected clocks, and virtual reality goggles. This study aims to recognize the innovative changes in global retail, identified from the analysis of publications conducted in high-impact journals.

The work has grouped the main study subjects of listed authors into categories demonstrating how retailers may work to make feasible an omnichannel retail strategy and transform their business in a disruptive way. This model should develop a complete harmonization between service delivery and channel engagement, allowing consumers to choose different ways to buy across channels.

Literature revision

The evolution of the research brought new definitions for retail omnichannel, influenced by the approach chosen by the authors. In different cases, definitions are noticed for distribution channels and, at the other extreme, those that approach the subject with consumer views. Interpretations are becoming more varied and, consequently, more productive from the conceptual point of view.

The review is organized by type of approach, seeking to group definitions by areas of identified knowledge, such as operations, technologies, consumer behaviors.

Beck and Rygl (2015) define omnichannel as “The set of activities involved in the sale of goods or services through all broadcast channels, whereby the consumer can activate the full channel interaction and or the retailer can control the complete channel."(p.174). The authors consider two sources of origin, consumers when they start a process of omnichannel purchases or retailers when they motivate customers by offering omnichannel models to carry out their purchases.

Juaneda-Ayensa et al. (2016) argue that the advancement of the internet and new technologies in the last decade have transformed the retail landscape. More and more channels are springing up, causing consumers to change their shopping habits and behavior. An omnichannel strategy is a form of retail that, by allowing real interaction, allows customers to shop on-the-go anywhere, at any time, providing them with a seamless, complete, and seamless shopping experience that divides barriers between channels.

There are already advances in more recent publications that propose conceptual models like Saghiri, Wilding, Mena, and Bourlakis (2017) that aims to coordinate processes and technologies in the channels of supply and sales. The proposed model can be applied to a wide range of retail supply chains, helping managers to develop, execute, and monitor omnichannel systems. This case demonstrates the search for tools and models to be applied by managers in their companies, given the urgency with which the subject circulates in the guidelines of business decisions.

Other studies indicate a strong influence of information technologies in retail and omnichannel as presented by Piotrowicz and Cuthbertson (2014) in which the authors highlight the use of smart mobile devices (smartphones) and social networks of That the growing importance of technology solutions in online stores creates new opportunities and challenges for retailers. As we have a fine line between physical and online ones, a new approach to the integration of these channels is emerging-the omnichannel, which aims to offer a customer experience “perfect " regardless of the channel.

The authors advance on the role of information technology in retail, new business models, and the future role of traditional stores as e-commerce and, in particular, m-commerce develops. The authors also point out that the main problems that emerged from the discussion included the need for channel integration, the impact of mobile technologies, the growing role of social media, changing the role of physical stores, the need to respond to the different requirements the dilemma between personalizations and privacy, and finally, the redesign of the supply chain. Thus, the authors' work converges on the issue of information technologies in the same way as Brynjolfsson, Hu, and Rahman (2013) who assert that the distinctions between the physical and the online are disappearing with the advances of technologies in smartphones and in which retailers must compete in a new and innovative way.

In an attempt to define an operational model, retail omnichannel has the following characteristics (Cummins; Peltier & Dixon, 2016): a) Selected shopping trips run by the consumer; b) Development of channels to act in synergy, unlike channels being developed in isolation, from beginning to end of the process; c) Inclusion of digital channels in the store's offer as a natural extension of the online service; d) Sophisticated segmentation of consumers, no longer segmenting into groups or clusters, assuming that each engages with a single preferred channel; (e) developing a single universal image and a portfolio of products and services covering all channels, as opposed to different brand channels with different offerings;

(f) Increased service modulation to allow channel transitions as opposed to an individual lock- in obligation for individual channels; g) Development of online complements for services based on the supply of physical goods.

One of the business processes that most catches the attention of companies is buying online with the withdrawal of purchase in the physical store. Gao and Su (2017a), explain that many retailers have recently begun to offer customers this purchase option. However, often, the impacts of such a deployment are not thoroughly evaluated. The authors present three findings that impact the operation of stores, in first, not all products are suitable for collection in the store, for example, low value-added products, second, the process allows retailers to conquer new customers and Thirdly, there is the possibility of sharing the sales result between the channels involved in order to avoid conflicts.

Gallino, Moreno, and Stamatopoulos (2017) demonstrate the omnichannel functionality that is the online purchase delivery in the closest store chosen by the customer. It is based on the hypothesis that retailers prioritize the transportation of products for which local demand is high, causing the sale of other products to be impaired by their absence in the pon-to-de-sale. The model promotes increased sales dispersion and suggests the readjustment of the inventory level.

In an approach about the customer buying experience, Hansen and Sia (2015) indicate that many organizations realize that they need an online presence to serve digital customers. However, offering a seamless customer experience across online and offline channels is increasingly challenging, corroborating the work of Juaneda-Ayensa et al. (2016). The study by Hummel, a European sportswear company, according to Hansen and Sia (2015), overcame the challenges and successfully passed the omnichannel retail. Based on this case, the authors provide insights to guide organizations with similar ambitions and implications for their CIOs (Chief Information Officer).

Rigby (2011) is more emphatic about retail processing. Today, e-commerce is well established, and digital retailing is already highly profitable. Still, the author commenting on the evolution of digital retailing and that the rapid transformation leads to something so different that requires a new name: omnichannel retail. This name reflects the fact that retailers will be able to interact with customers through numerous channels, websites, physical stores, kiosks, direct mail and catalogs, contact center, social networks, mobile devices (smartphones and tablets), Games, televisions, networked devices, home services, among others. Still, according to the author, if traditional retailers expect to survive, these should adopt the omnichannel retail and also transform the large Internet retailers that do not have stores, from liability in an asset. They must transform the purchases in a fun, exciting, and emotionally engaging experience by skillfully mixing the physique with the digital. They must also hire new types of talents, move away from outdated success measures, and become adherents of rapid test and learning methodologies-agile and frictionless. A successful omnichannel strategy should not only ensure the survival of a problem-free retailer in today's environment but also deliver a revolution in customer expectations and experiences.

In more rigorous research, Herhausen, Binder, Schoegel, and Herrmann (2015) examine the impact of offline retail integration, defined as the integration of access and knowledge about the offline channel in an online channel. Although channel integration (CI) has been recognized as a promising strategy for retailers, its effects on customer reactions to retailers and different channels are unclear. Based on technology adoption research and diffusion theory, the authors conceptualize a theoretical model where the perceived quality of service and the perceived risk of the Internet store mediate the impact of CI, while the Internet shopping experience of clients moderates the impact of CI. The authors then test the indirect and conditional effects of HF on search intentions, purchase intentions, and willingness to pay. Importantly, they differentiate the effects of the retailer level and the channel level, thus controlling the interdependencies between different channels. The results of the studies provide convergent evidence and show that CI leads to a competitive advantage through channel integration and enhances synergies rather than channel cannibalization. Customer buying experience over the internet moderates the impacts of channel integration. These findings have direct implications for marketers and retailers interested in understanding whether and how the integration of different channels affects customer outcomes.

For Bell, Gallia, and Moreno (2014), customers are increasingly omnichannel - implementing online and offline channels - into their thoughts and behaviors. To win in this new environment, just like Rigby (2011), retailers should also be omnichannel. This means having clear strategies for the channel's two core functions-delivering product information and product realization-and, delivering the right mix of experiences for customers. Bell et al. (2014) developed a customer-centric structure to deliver these strategies, based on empirical research with off-first retailers such as Crate & Barrel and online retailers such as Warby Parker. Traditionally or offline, retailers need to leverage the online channel not only for the achievement but also as a place for delivery of prices, inventory, and other information desired by customers. Using data from an experiment conducted at Crate & Barrel, a retailer of furniture, home décor, and home appliances (cookware, dinnerware), the authors show that by providing accurate pricing and inventory information online, a traditional retailer can significantly increase sales and traffic to offline stores.

Similarly, Warby Parker, a New York-based retailer specializing in eyewear that started selling online, sells products with features that some customers wish to experience offline. Bell et al. (2014) describe how the retailer experienced significant benefits when developing an offline presence. For Warby Parker, offline showrooms that provide product inventory to customers to prove increased sales through the online channel. Also, they observe the authors, when online retailers develop offline channels to provide information, this allows customers to rate more on the channel that best suits them. The authors also argue that the omnichannel strategies that discuss-strategies that balance the customer's need to obtain quality information and timeless satisfaction are the key to brand building and retail success. This, according to the authors, is true for traditional retailers, internet retailers focused on one product (pure-play) and hybrid retailers.

Corroborating with Warby Parker's model as the most innovative retailer by the National Retail Federation (NRF), Bell, Gallino, and Moreno (2018), the National Retail Federation focused on the relatively unspecified domain, the introduction of showrooms (physical locations where customers can see and experience products). The question was how showrooms benefit the two most fundamental objectives of retail: demand generation and operational efficiency? The result shows an increase in the sales of the retailer that starts to adopt the showrooming in general, both in the physical store and online; promotes the spillover effect for other channels, that is, it promotes the sale also in associated channels. Increases the convergence of purchases, that is, of the total number of customers that begin the purchase process, a more substantial portion of the purchase, and finally, the increase in the demand for expansion of the operational benefits provided to the customers. Sure, have a real environment where they can touch, experiment, or test products physically present, even if cannot take them immediately.

The article by Juaneda-Ayensa et al. (2016) is a work that is in an area that involves constructs of social psychology and information systems being much used in consumer behavior. It aims to identify the factors that influence the behavior of omnichannel consumers through the acceptance and intention to use new technologies during the purchasing process. To this end, a model was developed to explain the buying behavior of the omnichannel based on the variables used in the UTAUT2 model (Venkatesh, Thong & Xu, 2012) and two additional factors: social innovation and perceived security. The model was tested with a sample of 628 Spanish customers from the Zara chain of stores (Inditex Group) who used at least two channels during their last shopping day. The results indicate that the main determinants of the intention to buy in an omnichannel context are in order of importance: personal innovation, the expectation of effort, and expectation of performance.

In this same line, Gao and Su (2017b), in a second study, evaluate that the "information solves two types of uncertainty because in order to minimize the uncertainty of omnichannel consumers from the online and offline information supply efficiently. They get the product in the store, but they can end up returning when they buy it online) and uncertainty of availability (i.e., visits to the store are useless when consumers are faced with a lack of the product).” (p.2490). They present as results the importance of physical showrooms for retailers to reduce inventories, on the other hand, can reduce profits if there is excessive migration of customers to the virtual model due to its higher costs.

Another work, also Spanish, approaches the omnichannel in public services (Rey-Moreno & Medina-Molina, 2016), which attribute countless benefits to the application of electronic government, both for public organizations (higher efficiency, cost savings) citizens (accessibility, availability). According to the authors, for Spain, this has brought a generalized commitment from most governments to its implementation. Although the population is generally very satisfied with these new technological products, their adoption rates have stabilized. At the same time, the levels of use of traditional channels of interaction remained the same or, depending on the goal, increased. The main reason for this is possible that citizens see these new channels as a complement to traditional channels and not as an alternative, which can replace them. In order to gain widespread acceptance and use of electronic government, it is necessary to begin to know the needs of citizens. The marketing field has proposed different strategies to respond to this challenge. These range from multichannel management to multichannel marketing and an omnichannel experience. This paper presents the current situation of the development of electronic government in Spain, showing the real applicability and effectiveness of the strategies mentioned above to increase the rate of use of citizens concerning traditional management channels.

With this brief review of the literature it can be observed that the term omnichannel has its origin in the availability of new information technologies in retailing to meet a new customer who has an "omnichannel" thinking, since he adopts, in his day-by-day, strategies like Bring Your Own Device (BYOD) equivalent to entertainment onboard airlines like the App Latam Entertainment (LATAM) and Gogo Entertainment (GOL).

Method

A systematic review, in conjunction with quantitative content analysis (Krippendorff, 2014), serves as a guideline and constitutes the study object of this article. It is a method that assists in the organization, identification, and qualification of information contained in academic publications and, in parallel, uses a variety of tools and methods to study the content of textual information. In this way, the questions of Krippendorff (2014) are used, such as: What data are analyzed? How are they defined? What is the population from which they are drawn? What is the context in which the data are analyzed? What are the limits of the analysis? Moreover, finally, what is the target of inferences.

This article reports a systematic review of studies using quantitative methods of content analysis to examine papers on omnichannel in the Web of Science (WoS) and Scopus databases from 2011 to 2019. Was searched omnichannel studies published in journals peer-reviewed, identifying 56 articles in WoS and 59 articles in Scopus that meet the inclusion criteria. In this amount, there were 35 repeats, which resulted in 80 articles (56 from WoS and 24 from Scopus).

Was examine various attributes of the articles and analyze the differences over time. The use of systematic review techniques with quantitative content analysis makes a decisive contribution to the definition of the periodical publication lists and allows the analysis of future trends and demands. The analysis must accompany the scientific evolution of the publications of the various researchers on the same theme. Methods of a systematic review with quantitative content analysis can, however, be used qualitatively. The systematic review in this research delimits the field of research in the databases of web of science and Scopus facilitating the access and the organization of the articles collected and creating the opportunity to expand the studies related to the theme, using indicators that allow the comparison between the information obtained and allows estimating the occurrence of words of the scientific texts researched, the area of concentration, keywords in a given scientific text, the occurrence of words allows automatic thematic indexing, analysis of citations that allows grouping the bibliographical references included in publications by which authors and articles exert more significant influence or relevance (Price, 1965; Araújo, 2006).

The study was conducted from access to Web of Science (2018) and Scopus (2018), the survey was conducted on November 13, 2018, following the following path:

Step 1: Searches were performed with the word "omnichannel," without the delimitation of date, of the core collection of Web of Science, namely SCI-EXPANDED, SSCI, A&HCI, CPCI-S, CPCI-SSH, ESCI, delimiting only the field of research for Business, Economics, Management, and Business Finance. Thus, information about the total number of publications, thematic areas, types of publications, authors, titles, and their sources, institutions (universities), years of publications, languages, and countries were collected. The search originated the selection of 56 publications related to the searched topic. Similarly, Scopus's base for the "Business" sub-area was consulted, resulting in 59 articles.

Step 2: From the original 115 articles found, more relevant publications were selected on the topic omnichannel, eliminating redundancies (35 articles in the two datasets). Thus the final result corresponds to 80 articles.

Step 3: Quantitative content analysis by means of data mining tools with statistics such as: co-occurrence networks, that is, a distributional principle that refers to the possibility of distinct linguistic units occurring in combination with one another; hierarchical analysis of clusters; multidimensional scaling (MDS); Factorial analysis in order to visually represent the academic production in the subject. The citation evolution of the 80 articles; relationships of journals with higher impact; list of countries that have published the most articles on the subject; relations of the universities that publish the most; related to the theme are some of the analyzes. Step 4: Completing the analyses, we used the additional research on the authors, through bibliographical analyses, as well as total and partial readings of the leading articles. Although the research uses only secondary data, the study does not lose credibility as long as it uses reliable sources that guarantee the quality and the result of the study. Regardless of the reading of the articles, in this type of analysis, the keywords, the quotes, the abstracts, titles, periods, and authors are transformed into illustrations that enable the complementation of the analysis. It is used a set of R language packages for its execution, including TM, NLP, FactoMinerR, SnowballC, Wordcloud, cluster, among others.

An important point for text mining (frequency distribution of VRAs) is that our analysis was validated for the Zipfian distribution, with 247 keywords of the authors, which resulted in the following regression 2.963-0, 575X. For Lotka Law (0.709 + 3, 586X) with r. of 0.897 and P-value of 0.699.

Results and analysis

Through this systematic review with quantitative content analysis, it is possible to verify that there is a growing interest in omnichannel topics. This fact can be observed through the increasing academic production of articles, intensified in recent years. Some exogenous factors, such as the Internet boom (Rigby, 2011), the growth of e-commerce, and new formats adapted to these new markets, are aspects that prove the academic relevance of the theme.

Some critical data can thus be summarized for the 80 articles: 48 different journals, 282 Keywords-Plus (WoS exclusive), 247 author keywords, the average citation per article is 6.15, which demonstrates the youth of the topic as a research area. The total number of authors is 181, and only 17 of them produced isolated articles (a single author), and the other 164 worked cooperatively. The number of articles per author is still low (0.442), with an average of 2.26 authors per article and a collaboration index of 2.65. Production is recent, starting with an article in 2011 (Rigby, 2011), three in 2013 and 2014, five in 2015, and growing to 14 in 2016, 19 in 2017, 34 in 2018. An article from 2019 (Ovezmyradov & Kurata, 2019).

It is pertinent, for a systematic review with quantitative content analysis, to highlight the leading journals, or sources of publication, that contribute to the studies on the topic omnichannel. The primary sources of publication in the theme are (Impact Factor, JCR 2017, in parentheses): Harvard Business Review - HBR (4,374); MIT Sloan Management Review - SMR (2,583); Management Science (3,565); Journal of Retailing and Consumer Services (2,919); Journal of Business Research (2,509); Journal of Interactive Marketing (3,864); Journal of Retailing (5.48); MIS Quarterly Executive (1,862); Business Horizons (2,588); Journal of Innovation & Knowledge (Not available); Apparel (not available); Journal du Textile (not available); International Journal of Retail & Distribution Management (not available) and Marketing and Management of Innovations (not available). Thus, there is evidence that publication vehicles are diversified in a nascent area of research. The fact that HBR and SMR are more prominent for market and managers is because the theme arouses greater interest in management-oriented journals and less academic ones. Magazines such as the North American Apparel and Printing Impressions in the UK, such as Drapers and the International Journal of Retail & Distribution Management and the French Journal du Textile, help spread the word about omnichannel. Similarly, there are articles in business magazines such as Forbes, as well as consultancies such as McKinsey (Bianchi, Cermak & Dusek, 2016) as well as Rigby's article (2011) linked to Bain & Co.

Concerning the languages of publication, English is the majority. Among those in a non- English language, and in Portuguese, Webber, Vanin, and Severo (2016), which is in agreement with the literature on omnichannel. According to the authors, "The process of retail innovation (...) has been able to identify the use of technologies as innovative tools to promote new consumer shopping experiences and the importance of the areas of marketing and information technology, as well as the alignment of distribution channels identified as omnichannel” (p.3377).

In relation to the countries that publish the most on the subject, the United States has a total of 25 articles, followed by China with five, Brazil, Poland, Switzerland and the United Kingdom with three each, and, finally, Australia, Georgia, Germany, Italy, Sweden and Ukraine with two each. Here an absolute predominance of texts in American magazines and authors. In relation to the citations the United States continues in the lead as 211 citations, followed by Switzerland with 66, Georgia with 28, Denmark with 18, United Kingdom with 13, China with eight and Spain with only four citations, for a country that counts on Zara fashion retailer that should be one of the motivations of production on omnichannel in that country. As for the production of articles among multiple nations, Denmark is the one with the most significant participation (100%) followed by China (60%). The greatest endogeny is with Brazilian, Polish, Italian, Ukrainian, Japanese, and Korean authors all without international partners.

Regarding the universities and research centers related to the topic, we have the University of Pennsylvania, Dartmouth College, Northwestern University, Babson College, Georgia Institute of Technology (Georgia Tech), Temple University, Bentley Univ., and Carnegie Mellon Univ., all Americans. Among the Europeans is the Copenhagen Business School (Denmark), Stockholm Univ. (Sweden), Cambridge and Oxford (England), Univ Lodz (Poland), Univ. St. Gallen (Switzerland), from Asia to Univ. Sci. & Technology (China), Chinese Univ. Hong Kong (China), City Univ. Hong Kong (China), and Curtin Univ. (Australia). There is work from Cisco Systems (United States).

Georgia Tech owes the lead in the work on the subject to Professor Yu "Jeffrey" Hu, current Program Director of China, Co-Director of the Center for Business Analysis and Associate Director of Master of Analytical Studies at the Georgia Institute of Technology Scheller College of Business. He is also a member of the MIT Digital Economy Initiative. He specializes in big data, business analysis, e-commerce, mobile commerce, social media, consumer behavior, and online advertising. Their researches use empirical and analytical models to study social media, mobile commerce, e-commerce, omnichannel retailing, assortment/variety decision of retailers' products, consumer behavior in online and offline shopping. He also wrote articles on pricing models for online advertising and protecting the privacy of online consumers. Professor Hu is the co-author of a classic of the area (Brynjolfsson, Hu & Rahman, 2013). According to the Web of Science (2018), "Business Economics" has 34 articles, followed by "Operations Research & Management Science" with nine articles, and "Computer Science" with seven articles. This highlights the importance of not only the business area but also of Computer Science, as well as studies in operational research. On the one hand, there are more theoretical works on a theme under construction.

In relation to the most productive authors: Gao and Su (2017a, 2017b, 2018), Mo-Reno (Bell, Gallia & Moreno, 2014, Gallino, Moreno & Stamatopoulos, 2017, Bell, Gallino & Moreno, 2018), Bell (Bell, Gallia & Moreno, 2014; Bell, Gallino & Moreno, 2018; Castillo, Bell, Rose & Rodrigues, 2018), Dzyabura (Dzyabura & Jagabathula, 2018), Gallino (Gallino, Moreno & Stamatopoulos, 2017; Bell, Gallino & Moreno, 2018), Ieva (Ieva & Ziliani, 2018), Jagabathula (Dzyabura & Jagabathula, 2018), Li (Li et al., 2018, Shen et al., 2018), Pelton (Dai & Pelton, 2018) and Ziliani (Ieva & Ziliani, 2018). A critical analysis is the articles with the highest number of citations. Brynjolfsson, Hu and Rahman (2013) is the most cited followed by Herhausen, Binder, Schoegel and Hermann (2015), Rigby (2011), Bell, Gallia and Moreno (2014), Savelsbergh (2016), Hansen and Sia (2015),Gao and Su (2017a), Saghiri, Wilding, Mena and Bourla-Kis (2017), Gallino, Moreno and Stamatopoulos (2017), Bell, Gallino and Moreno (2018), Gao and Su (2017b), Chatterjee and Kumar (2017) and Parise, Guinan and Kafka (2016). The work of Sa-Velsbergh (2016) on logistics challenges was maintained in our analysis. Among the most cited is the role of dissemination of journals such as the MIT Sloan Management Review and the Harvard Business Review for the theme in addition to the Journal of Retail and the International Journal of Retail & Distribution Management. Figure 1 presents the factorial map of the most cited articles in the research field and consists of three clusters.

Cluster # 1 represented solely by Shen et al. (2018) with work on quality of channel integration, perceived fluency and use of omnichannel service: The classification functions of experience mode of internal and external use.

Cluster # 2 represented solely by Li et al. (2018) with an article on the customer's reaction to the integration between channels in the omnichannel retail: the mediators of the retailer's uncertainty, the attractiveness of identity and the costs of exchange.

The third cluster # 3, more diversified, consists of the following articles: He-Rhausen et al. (2015) on the integration of physical stores with clicks: Results at the retailer level and the channel level of the integration of online and offline channels. Saghiri et al. (2017), with an article on the directions towards a three-dimensional structure for the omnichannel; Gao and Su (2017a) in an article on online and offline information for omnichannel retail; Gao and Su (2017b) in an article on omnichannel retail operations with buy-online-and-pick-up-in-store. Bell et al. (2014) on how to win in an omnichannel world, again Bell et al. (2018) in working on demand and operational benefits of the offline showrooms in the Omnichannel retail, and finally Gallino et al. (2017) an article on the integration of channels, Sales and inventory management. Another way of looking at the research area is by the authors who constitute its conceptual basis, its roots, the most referenced authors.

Brynjolfsson, Hu and Rahman (2013) also leads in this regard, followed by Verhoef, Kannan and Innan (2015), in a special issue on multichannel retail in the Journal of Retailing, Cao and Li (2015) on the impact of cross-channel integration on retail sales growth, Piotrowicz and Cuthbertson (2014) in another special issue on information technology in retail and the omnichannel of the International Journal of Electronic Commerce, Gallino and Moreno (2014) in an article about the integration between online and offline retail channels, Rigby (2011), Neslin et al. (2006) in an article about challenges and opportunities in multichannel customer management, Bell et al. (2014), Herhausen et al. (2015), Verhoef, Neslin and Vroomen (2007) in an article on multichannel client management, Zhang et al. (2010) in an article on integrated multichannel retail strategies, Avery et al. (2012) on cross-channel elasticity prediction and Beck and Rygl (2015) in a paper categorizing multichannel retail, cross-channel and omnichannel for retail. For the frequency of words, we have, as shown in Figure 2, omnichannel (43), retail (30), management (14), mobile (10), channel (9), Customer (8), multichannel operations (7). Marketing (7), integration (6), the consumer (6), strategy (6), experience (5), technology (5), eCommerce (5), and e-commerce (5).

Specifically concerning the correlation between the words, the software was refed several times with terms of the previous rounds and with the Pearson correlation (r > 0.25), and thus, we obtained the association between the most relevant words. Here are some of these associations and their Pearson coefficient. With omnichannel, you only have retail (0.31) and multichannel (0.29). For the word Mobile has: apps (0.76), purchasing (0.75), Commerce (0.58), information sharing (0.53), sharing (0.53), social (0.35) and information (0.27). For the word channel has: integration (0.65), cannibalization (0.55), Integration Channel (0.55), Pay (0.55), willingness (0.55), Supply Chain (0.55), Visibility (0.55), synergies (0.37), online (0.28), and, with R = 0.26, for channel correlation with Following words: Dispersion long, empirical, sales, tail, fluency, usage experience, empowerment, responses, S-O-R (Stimuli- Organism-Response) framework, consumer returns, ship to store and booking. For the word journey, we have the following correlations: interaction (1.00), the customer (0.57), Choice (0.49). For the word experience, you have: customer, intentions, and services with R = 0.75, loyalty (0.52), attributes, interface, marketing operations, methods, quasi-experimental, showrooms, interaction, booking, and choice with r = 0.36. For touchpoints, you have: Loyalty (1.00), class, cluster, latent segmentation, intentions, and services all with 0.70 and, finally, with 0.39, customer, and analysis.

Regarding quantitative content analysis, we started by data reduction techniques (Cooper & Schindler, 2016). The Multidimensional Scaling (MDS) (Figure 3) of the keywords is displayed. To analyze the limited data, where each document contains a small number of words, and each word appears only in a limited number of documents. MDS takes a set of dissimilarities and returns a set of points so that the Euclidean distances between these points are roughly equal to the differences. In Figure 3, from right to left you to have: omnichannel and retail (retailing) following for management, mobile, channel, customer, multichannel, operations, marketing, integration, consumer, strategy, experience, technology, e-commerce, commerce, Logistics, Value, model and final choice. The emphasis is on the management of the mobile, the channels, and its integration towards the consumer and its experience, new models of value delivery compared to the traditional.

Hierarchical cluster analysis is a data mining tool for dividing a multivariate dataset into "natural" clusters. We use methods to explore whether previously undefined clusters may exist in the dataset. Cluster analysis is used when we believe that sample units come from an unknown number of distinct populations or subpopulations. We also assume that sample units come from several distinct populations, but there is no a priori definition of these populations. We aim to describe these populations using the observed data.

When presenting the dendrogram in six clusters (Figure 4), we can see that it corroborates with the previous analysis. Omnichannel and retail (includes retailing) constitute their cluster, such as mobile. Another significant cluster is the integration of channels as technology management and operations. Finally, a sixth cluster wherefrom the consumer/customer, we have the definitions of e-commerce strategies and multichannel marketing.

As seen, the adoption and management of the Internet and the technologies are means, as well as the management of operations. With the increase of the technologies, we can offer more products online, and here the role of the mobile happens to be of first greatness. The technology has enabled the creation of a model that provides different channels of purchase where the experience has its value effect. The distribution allows new retail. Traditional marketing is challenged by the consumer "omnichannel." The big challenge for the retailer is to shop online on a mobile device.

The creation of a network diagram (Figure 5) shows the words with similar pattern patterns, that is, with high degrees of co-occurrence, connected with lines. Because words are connected with lines, it may be easier to understand the co-occurrence structures of words, compared to multidimensional scaling (Figure 3), which outlines the words. This analysis corroborates the previous ones in a more emphatically way.

For the network metrics, Keywords Plus was used in this research as a parameter for capturing the content and scientific concepts presented in the articles, according to Zhang et al. (2016). These metrics can be summarized as: size (282); Density (0.043); Transitivity (0.484); Diameter (5); Degree of centrality (0.171); Centrality Closeness (0.007); Centrality Betweenness (0.094); Eigenvector centrality (0.842); Average Path Length – APL (2.66). Some metrics were also used, such as PageRank score, hub score, authority score, as shown in table 1.

These metrics have implications such as the impact of the omnichannel (Cao & Li, 2015), the importance of journal special issues such as the work of Verhoef, Kannan and Innan (2015) and Piotrowicz and Cuthbertson (2014), as well as the importance of multi-channel client management such as the work of Neslin et al. (2006) and Verhoef, Neslin and Vroomen (2017). They are complementing the analysis of the importance of the concepts of supply chain and the technologies involved with e-commerce as well as behavioral models.

Conclusion

This article was dedicated to the academic production of omnichannel between 2011 and 2019, through a systematic review carried out together with quantitative content analysis, in order to identify how retail innovations have been registered by scientists when the subject is omnichannel. We analyzed 80 articles selected in Web of Science and Scopus from the use of the search term and delimitations, and the result was analyzed with the help of text mining techniques and quantitative content analysis.

In a world where retail impacts the behavior and lifestyle of consumers and new technologies focused on mobile devices and, in particular, smartphones, the shopping experience plays a vital role. The evolution to the omnichannel goes through the question of channel strategy, starting in the physical stores that become part of the shopping experience evolving to a combination of channels (e-commerce, apps, email), cross-channel making them work together by further impacting marketing planning. Finally, the omnichannel with the simultaneous use of more than one channel placing the consumer at the center of the shopping experience. In addition to the question of relationship, analytical techniques are required for new management models.

The analysis highlighted words like customer and experience. Omnichannel, according to this analysis, is a strategy centered on the consumer buying experience, built for him, so the perceived value of it resides in perceiving an advantage in the purchasing experience compared to those supported only in physical stores or in online retail. The literature associates the Omnichannel retail strategy with the channel strategy, with a lot of customer proximity and experience. This finding suggests the construction of an omnichannel retail strategy from the redesign of the retailer's channel strategy.

Omnichannel as a new retail strategy based on the use of on-and off-line channels (store) and mobile technology targeted at your client. We have the experience, straight retailing, multichannel customer management, online, and information technology, demonstrating what the omnichannel strategy has on its base. Based on different approaches in the articles analyzed, retail innovation goes through the omnichannel strategy that focuses on the proposition of new and perfect experiences for retailers ' customers, leaving in the condition to help other terms identified in the research.

Every evolution present in human inventiveness seeks to shorten the path to achieving consumer satisfaction with consumption, and from then on, guaranteeing gave could fidelity concerning the brands with which it identifies, without other factors being able to influence this relationship negatively. Many of the most impactful studies are based on journals such as HBR, SMR, in addition to the role of consultancies and journals in Computer Science, which demonstrates the youth of the theme. Behavioral studies begin to emerge in research. Future studies should advance in the issue and provide new findings until the consolidation of a theory capable of delineating the complete omnichannel marketing strategy for an omnichannel consumer.

The techniques used, be it bibliometrics or quantitative content analysis (text analytics), open up many possibilities for insights that may have been overlooked by the authors. We sought to use sophisticated analysis techniques based on the web of science and Scopus. However, because it is a new area of research, many trial materials or white papers from consulting firms or information technology can bring new subsidies. As for the methods of analysis, many were not used in this research, especially their visualization outputs. Factorial maps of the most significant contributions of the field, co-word analysis, co-citation networks, collaborative network among countries, author collaboration network, coupling network, more detailed network statistics , h-index of authors, self-organizing maps (SOM), word association maps, feelings analysis, machine learning algorithms for modeling topics such as LDA (Latent Dirichlet allocation) or CTM (Correlated Topic Model). Like research in omnichannel, these research methods are in their infancy.

Among some research, topics are the issue of the consumer behavior, the shopping journey, the shopping experience, the services, the channels, the technologies, the Internet, the loyalty, engagement, the e-commerce, the multichannel customer management, the Analytical tools, and algorithms.

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