The Effect of Using Social Media in the Modern Marketing Communication on the Shaping an External Employer’s Image

: The aim of this article was to determine the signiﬁcance of modern marketing communication channels used in the process of shaping the external image of an enterprise as an employer. An analysis of the world literature on marketing, management, marketing communication and human resource management was used to prepare the theoretical part. The results of the analysis indicate a cognitive and research gap regarding the use of modern communication channels for building the external image of an enterprise in the role of an employer. In order to reduce the gap, empirical studies were conducted among young Polish potential employees, in which the survey method was used to gather primary data. The collected data were subjected to statistical analysis, during which the following methods and statistical tests were applied: the analysis of average values, exploratory factor analysis, Kruskal–Wallis test (KW), Pearson chi-square independence test and V-Cramer coefﬁcient analysis. The results of the analyses conducted indicate, inter alia, that statistically signiﬁcant diversity was identiﬁed in the case of non-professional media in terms of respondents’ opinions on whether the employer’s image created by modern media is better than the employer’s image created on the basis of classical marketing communication channels. In the case of professional and non-professional media, the age of the respondents was not a differentiating feature. Moreover, neither for professional media nor for non-professional media were statistically signiﬁcant dependencies identiﬁed between respondents’ opinions on the impact of actions undertaken by enterprises on shaping their positive external image as an employer and respondents’ opinions on whether the employer’s image created on the basis of modern marketing communication channels is more beneﬁcial than the employer’s image created on the basis of classical marketing communication channels. The results obtained on the basis of the research have a cognitive and applicability value, characterized by originality. Until now, the importance of using modern marketing communication channels in shaping the employer’s external image has not been analysed. This also applies to enterprises operating on the energy market.


Introduction
In order to develop or at least maintain their current market position, contemporary enterprises are forced to constantly search for sources of a relatively long-lasting competitive advantage [1,2]. Extremely important, unique sources of such an advantage are intangible assets, such as employees [3], knowledge [4] and positive image of an enterprise [5][6][7], including the image as an employer. These sources are very important for each enterprise, including energy companies. Competing for talented employees has become almost as important for enterprises as competing for external customers [8][9][10] leading to sustainable development.

The Image of an Enterprise as an Employer
The most general definition of an image is a way of perceiving someone or something or a picture created in a recipient's mind [42]. In the literature on management, company image is treated in terms of a derivative of an organization's identity and the ways in which the organization communicates with its stakeholders [43]. Sometimes the image is wrongly identified with identity or even with a brand. In addition, new "brand image" thinking constructs are created [44,45], whose introduction to the academic discussion only introduces conceptual chaos.
According to Alvesson [46], company image is a holistic picture of an organization in the minds of entities from its surroundings. This picture is a result of shared values of members of a given organization, which are passed on to entities from its surroundings in the form of intentionally designed information. A similar way of defining company image is also presented by Hatch, and Schultz [47].
In turn, Dowling defines image as a "set of meanings that allow a given subject to be identified, described, remembered and referred to" [48]. Image is a direct picture of a given enterprise shaped in the minds of recipients [49].
Therefore, company image can be identified with a set of information and opinions about the company as an employer, a client, a community, a supplier and a participant of a corporation. It is a mental picture which arises in the minds of stakeholders, based on specific activities of the organization [50].
Company image can also be considered as a way of receiving a message of the nature of self-presentation by recipients interpreting the message in a broader context and in relation to their own reference framework [51].
According to Fombrun and Van Riel [52], company image is a result of the assessment of an enterprise by other entities, and the assessment refers to the way the entities perceive the previous and planned activities of the organization and compare them with the activities of its leading market rivals.
Ferrell and Hartline [53] point out that company image may include positive and negative impressions, which result from the company's past and present activity and from the perception of the actions it may take in the future.
The overall company image is the sum of its many sub-images, which include the image as an employer [54]. Minchington [55], defining the essence of the image of an enterprise as an employer, focuses on the perception of an organization as a workplace by its current employees, as well as other entities interested in this issue.
According to Jenner and Taylor [56], the image of an enterprise as an employer reflects the efforts of the organization oriented towards communication with internal and external recipients, as a result of which the enterprise is perceived as a desirable and distinctive employer. Martin [57] also narrows the definition of employer's image to the so-called desired image; according to him, the image is what senior management wants to convey to public opinion about the package of functional, economic and psychological benefits offered by a given company. Martin also emphasizes that this image is characterized by a large dose of subjectivism. This results, among other things, from the fact that the information provided can be received in a different way depending on how important it is to its particular addressees [57]. The analyses so far have focused mainly on a formal shaping of the image by an enterprise as an employer.
A characteristic feature of the image of an enterprise as an employer is the fact that it can be shaped both by internal and external recipients. This bidirectionality evidently affects the effects of shaping the image of an enterprise as an employer. Current employees (internal recipients) perceive an enterprise as an employer on the basis of their personal experience related to horizontal interpersonal relationships (between employees of the same level of organization) and vertical interpersonal relationships (between subordinates and superiors). Positive relations occurring between the organization's members in both of these systems have a positive impact on shaping the image of the enterprise as an employer among current employees. Their opinions reach participants of the external labour market.
Therefore, another area in which an enterprise should shape its image as an employer is its environment, including people appearing in the role of potential employees and people having direct relationships with them [54]. Baruk defines the image of an enterprise as an employer as "a picture (reflection) shaped in the awareness of current and potential employees based on their experience (in the case of people employed in the company) or information reaching potential members of the organization, whose source are people creating a given organization and all types of mass media" [54]. This image, both in the formal and informal dimension, can be shaped by means of classical and modern marketing communication channels, including social media.

Modern Marketing Communication Channels
People responsible for planning communication marketing activities in enterprises have been facing a serious challenge since the beginning of the 21st century. On the one hand, they have at their disposal a significant number of marketing communication channels, and on the other hand, they must skilfully coordinate the channels, creating their proper composition based on constant verification of their applicability. According to many researchers, traditional marketing communication channels, such as radio, television, newspapers, etc., will gradually lose their importance [58,59] for modern communication channels. That is why it is extremely important to define the channels unequivocally.
In the literature on the subject, one can come across many definitions of modern channels and modern media. Some of the definitions emphasize that a group of modern media consists of websites and other forms of digital communication, as well as information channels, in which active consumers are involved [60]. According to Pratt [61], modern (or new) media are inextricably linked with multimedia, and he claims that new media include all multimedia systems on-line, multimedia systems on the disk and multimedia systems connected with the development of technology for broadcasting or recording text, sound and image.
In turn, Manovich [62] points out that in most cases new media are identified with the dissemination and sharing of information by means of a computer. According to him, this way of defining new media is too simplistic and does not fully present the complexity of the issue, which cannot be argued with. New media are distinguished by the following features [62]: (1) numerical coding (the object of new media has a digital record that allows the object to be changed for example by using an appropriate algorithm); (2) modularity (the object of new media is created by a huge number of independent parts, able to function in an autonomous way); (3) automation (the use of an appropriate algorithm allows the entire object to be diametrically changed); (4) volatility (the object of new media may occur almost in an unlimited number of versions); (5) cultural transcoding.
On the other hand, some authors (including Lister, et al. [63]) believe that new media can be seen through the prism of adjectives that allow them to be described. New media are digital, interactive, hypertext, virtual, network and simulated. It is, however, worth emphasizing that not all of the above features must be present at the same time and with the same intensity.
In turn, according to Winer [64], the characteristics of new media can be limited to two features that distinguish them from traditional media. According to this author, these characteristics are interactivity and their digital character.
An interesting definition of new media was proposed by Witczak [65]. According to him, new media should be defined as a digital process of creating and disseminating as well as processing, exchanging and storing some information which is subject to social communication of an individual and mass character. The key technologies that dynamize the development of new media are the Internet and mobile telephony.
As can be seen, taking into account the approaches applied, all definitions of modern (new) media can be divided into the following three basic groups: technological definitions, attribute definitions and process definitions.
Rapid technological development has meant that nowadays practically every recipient of communication activities can post their opinions about a given offeror, including an employer, on the Internet network platforms. The combination of these platforms together with applications enabling the collection of information has made it possible to obtain specific information about the employer immediately, at all times and from almost anywhere on earth [66], being able to respond to them without deferring in time.
Before the emergence of new media, employees were able to express their opinions and share their experience about an employer usually within internal communication systems, which were created and controlled by the employer himself/herself [67]. This meant that the possibility for free expression was limited.
The dynamic development of new media has made marketing communication methods of enterprises with the environment undergo quick changes. More and more organizations are taking advantage of modern marketing communication channels in their activities. This results, among other things, in the increased interest of researchers in issues related to social media marketing, digital marketing and mobile marketing [68][69][70][71][72][73][74].
The results of an analysis of the literature on the subject indicate that research is being conducted on the use of modern marketing communication channels in human resource management, yet it is mainly limited to recruitment activities [75,76]. However, the use of modern marketing communication channels in the process of shaping the image of an enterprise as an employer, especially from the perspective of employees, is still not being analysed.
Marketing channels based on the media include social media. According to Kaplan, and Haenlien, media include "a group of Internet applications based on ideological and technological principles of Web 2.0 and enabling the creation and exchange of usergenerated content" [77]. At this point, it is worth emphasizing that in Web 2.0, unlike Web 1.0, platform users are no longer just recipients of information, but also co-creators [78]. Social media are similarly defined by other authors (including [79]), who identify them with Internet applications based on Web 2.0. Some authors defining social media, however, exhibit more aspects related to information resources that enable interaction and creation of network communities (inter alia [80,81]).
Social media are characterized by openness, fast information exchange and high level of user involvement. They create a virtual environment where one can express and exchange opinions, share experiences, distribute and control other information anywhere and anytime [82,83]. Social media enable social interactions to take place between people who would not make contact in any other way [84]. It means that they change individual and group behaviours [85] in each area of life.
In the case of personnel activity, employees, using social media and running their own blog, can express not only positive but also negative opinions about their employer. This may have a significant adverse effect on company image, both among potential employees and other stakeholders [7]. Despite the fact that an increasing number of enterprises are deciding to take actions aimed at shaping their image as an employer [86], it is worth remembering that social media are much more difficult to manage, as well as control [87,88]. Therefore, enterprises should carefully select social media in which they publish information about themselves, especially in relation to fulfilling the role of employer [89].
The most well-known and widely used social media include Facebook (social networking site), Twitter (microblog), YouTube (site for posting videos), Instagram (portal for posting photos) and specialized social media platforms, such as LinkedIn and Golden-Line (portals with a recruitment and professional-business profile). Research conducted by O'Connor, Schmidt and Drouin [90] showed that 86% of employees have co-workers among friends in social media, and 77% of people use social media while working. From the point of view of the subject matter of this article, it is also important that 44% of people provide information about their work via social media [90]. Additionally, during the financial crisis, Facebook became the main social platform where users sought business contacts and new places of employment [91].
Mobile marketing is another marketing channel based on new media [92]. According to Kaplan, mobile marketing can be described as "any marketing activity carried out by means of the ubiquitous network, with which consumers are constantly connected through a personal mobile device" [93]. Mobile marketing may include actions within enterprise communication with customers using short text messages (SMS), QR codes and websites displayed on mobile devices [94] but also the transmission of picture messages (MMS) and image advertising on the screens of mobile devices.
While SMSs and MMSs have not found wider use as image-creating instruments, mobile social marketing has started to play a significant role in shaping company image as an employer. The creation of mobile marketing was related to the fact that the proliferation of the mobile Internet resulted in a specific combination of mobile communication with the classical Internet. However, the increase in the interest in social media meant that people using portals and social applications, wanting to be in constant contact with other users, started using mobile devices for this purpose [73]. An advantage of this combination was the ceasing of restrictions on the time and place of the receipt of a marketing message. Internet access via mobile devices has meant that enterprises can communicate with their employees not only during their work and travel but also during leisure [38]. The specific inseparable link between an employee and an employer can be treated as a negative consequence of the use of social media in marketing communication, which has a clear image overtone.
However, in practice, social media are still used rather as marketing communication channels regarding an offer of a given company [95]. This is clearly evident on the energy market. Social media are used in this case to identify consumers' attitudes towards renewable energy [96], level of environmental consumers' awareness [97], stakeholders' opinions [98], etc.
Application of social media in personnel policy is very limited, although social media can successfully be used for activities aimed at creating a positive image of an enterprise as an employer. This statement applies to enterprises functioning on different markets, inter alia, energy market where often no attention is paid to employer's image [99]. It is clearly visible even though each energy company acts also as an employer. That is why the aspects connected with creating the employer's image, especially external one, are as important for these firms as for the other companies. In the case of enterprises on the energy market, shaping their image in the role of employer is especially significant because of the importance of this industry for the economy on a regional, national and global scale.
In order to reduce the identified cognitive and research gap, the following research hypotheses were verified: Hypothesis 1. Respondents' attitude towards the use of modern communication channels for image-related purposes is a feature that differentiates opinions regarding activities that affect the shaping of a positive external image of an employer.

Hypothesis 2.
There is a dependence between organizing promotional campaigns on non-professional social media (Facebook, Instagram) showing an enterprise as an attractive employer and respondents' opinions regarding the use of modern communication channels for image-related purposes.

Hypothesis 3.
There is a dependence between organizing promotional campaigns on professional social media (LinkedIn, GoldenLine) showing an enterprise as an attractive employer and respondents' opinions regarding the use of modern communication channels for image-related purposes.

Hypothesis 4.
The age of respondents is a feature that differentiates opinions regarding activities that affect the shaping of a positive external image of an employer.

Research Methodology
Primary empirical research was conducted using the socio-psychological method of a questionnaire developed by the authors of the article. The research was carried out at the end of 2020. Its subjective scope included 430 people aged between 18 and 45 years old (the so-called mobile age) representing Polish users of social media. The selection of the research sample was conducted using quota-sampling and targeting. The population frame was data provided by the Central Statistical Office. Most of the respondents, like in the case of the structure of the general population, were women (58%). In terms of age structure, the majority of respondents had 36-45 years (40%). The rest of the respondents had, respectively, 26-35 years (38%) and 25 years or less (22%). This structure corresponded to the structure of the general population of adult Poles aged 18-45.
The research was Internet-based. The choice of the form of the research was conditioned by the adopted assumption that only active users of the Internet would be included in the study. The Computer Assisted Web Interview (CAWI) method was used, using the option of creating online questionnaires made available on the Google Forms platform.
In order to determine the importance of using modern forms of marketing communication in the context of the perception of an enterprise as an employer by the participants of the external labour market, the research included fifteen activities undertaken by employers in relation to employees. The actions were selected based on the results of a cognitivecritical analysis of the literature on the subject and on the results of unstructured interviews conducted among 25 people before the creation of the authors' original questionnaire. For each activity, the respondents were asked to determine its impact on shaping a positive image of an employer, using the Likert scale, which is one of the most fundamental psychometric tools in the social sciences [100]. In this article, a five-stage version of the Likert scale was used, in which the mark 1 meant that a given activity definitely has no impact; 2-it is unlikely to have an impact; 3-it is hard to say; 4-it is likely to have some impact; 5-it definitely has an impact. In accordance with the approach presented in the literature, among the analysed activities undertaken by employers, professional social media (such as LinkedIn) and non-professional social media (such as Facebook) were treated as two separate categories [101].
The primary data collected were subjected to quantitative analysis including methods and tests of statistical analysis, such as the analysis of average values, exploratory factor analysis, Kruskal-Wallis test (KW), Pearson chi-square independence test and V-Cramer analysis. The application of the Likert scale was a prerequisite for the application of the first two methods. The chi-square test was applied to determine whether there are dependencies between the variables analysed, and the V-Cramer coefficient was applied to determine the strength of the dependencies between the analysed variables.
The Kruskal-Wallis test allows an answer to be found as to whether the diversity in terms of separating individual groups (e.g., respondents' opinions, respondents' age) is statistically significant enough to say that the respondents' opinion determined by the analysed response is significantly different. It is a non-parametric equivalent of ANOVA [102]. It consists in checking whether the number of independent results from a group comes from the same population or from a population with the same median. Individual samples do not have to be of the same number. The input data are an n-element statistical sample divided into "k" of disjointed groups with numbers ranging from n1 to nk.
The explorative factor analysis allows an in-depth analysis of the collected primary data. It is used to reduce the number of variables constituting primary data obtained from surveys and to detect structures in relationships between these variables, that is to classify them. In order to determine the number of common factors (the so-called main components), the Kaiser criterion method was used to leave only those factors with eigenvalues greater than 1. Each factor explains a certain level of overall variability of the system under consideration, determined by a percentage of variance that can be interpreted as a measure of explanation of the problem. Within individual factors, the variables with the highest factor loadings against given factors were distinguished (value ≥0.7 was assumed) [103,104].
Factor analysis does not enable the answer to be found as to whether the diversity in terms of separating individual groups is statistically significant enough to say that the respondents' answers determined by the analysed response are significantly different. The Kruskal-Wallis test is used to answer this question. The higher the value with a satisfactory level of significance, the greater the diversity.
The statistical analysis was performed using the IBM SPSS Statistics Ver. 22 package.

Respondents' Opinions about Communication Activities Undertaken by Enterprises on Shaping Their Positive External Image as an Employer
For all of the fifteen actions analysed, in total more than half of the respondents believed that they exert a greater or lesser impact on the beneficial perception of an employer, and more than 50% of people clearly expressed such an opinion in relation to the organization of paid internships (Table 1). In turn, the highest percentage of the respondents in total claimed that the creation of a positive image of an employer is not affected by organizing promotional campaigns on the radio showing a company as an attractive employer. It was the only activity for which the percentage exceeded 20%, amounting to 23.1%. At the same time, it was the only activity whose average rating was less than 3.50. 1-definitely has no impact; 2-is unlikely to have an impact; 3-hard to say; 4-is likely to have an impact; 5-definitely has an impact.
It is worth noting that both activities involving the use of social media in image-related campaigns also obtained relatively low average ratings not exceeding the value of 3.70. They took respectively the 13th and 9th positions in the overall hierarchy of the activities analysed. It should be added that the use of professional social media gained a clearly lower average rating.
Within the fifteen activities analysed, five of them obtained an average rating exceeding the limit of 4.00, although none of the activities gained an assessment of at least 4.50, despite the five-point scale. Three activities with the largest average ratings had a common feature, which is the creation of conditions for acquiring new skills and/or knowledge by an employer. They were connected with internships programmes, work experience (but only paid) and training. Therefore, it can be assumed that the respondents paid a lot of attention to offering employees opportunities for professional development, noticing the close relationship between the employer's care for those aspects and the employer's image. The two remaining activities, which received average scores of at least 4.00, also referred to an active increase in knowledge, yet with respect to potential employees who are the participants of the external labour market.
On the other hand, the organization of promotional campaigns aimed at shaping the image of a company as an attractive employer obtained average ratings with much lower values, regardless of whether it was about using traditional or modern forms of communication in these activities. In addition, targeting via TV received an average rating with a slightly higher value than the use of professional social media for this purpose, which is of great significance considering the subject matter of this article. It can be concluded that the creation of opportunities for development turned out to be relatively more important from the point of view of the perception of an employer by participants of the external labour market than undertaking typical promotional activities.
The respondents were also asked whether an employer's image created by modern marketing communication channels (including the Internet and mobile applications) is more beneficial than the image built by means of classical channels (including press, television and the radio). It turns out that the majority of respondents in (53.64%) believed that the effect of using modern channels is a more favourable image, although only 7.58% expressed such an opinion. In total, almost every fourth person (23.94%) was of the opposite opinion, claiming that the image built thanks to modern channels is not better than the image shaped using traditional channels. It is worth adding that 4.55% of people categorically expressed such an opinion. It is also characteristic that as many as 22.42% of respondents did not have an opinion on this matter.
The answers to this question only apparently do not confirm the results presented in the previous considerations. It should be remembered that this question concerned the overall image of an employer, without distinguishing the external and internal image, and modern communication channels, without limiting the analysis to social media. Therefore, the question was more general than the question concerning actions taken by an employer analysed before. However, it seems important to identify whether respondents' opinions regarding the comparison of the image obtained thanks to modern and classical communication channels are significant when it comes to the role of individual actions of employers in shaping their external image as offerors of personal values.

Respondents' Structure Depending on Their Opinions on Whether the Employer's Image Created on the Basis of Modern Marketing Communication Channels Is More Beneficial Than the Employer's Image Created on the Basis of Classical Marketing Communication Channels
In order to identify the structure of the phenomenon studied, in particular, to compare the significance attributed to individual activities by the total of the respondents by the respondents who believe that the image shaped by modern channels is more beneficial than the image constructed using classical channels and by the respondents with a different opinion in this regard, an exploratory factor analysis was carried out for each of the three groups of the respondents. In order to conduct the analysis, the indications "definitely yes" and "rather yes" were merged, treating the respondents who gave such responses as one group agreeing that the image constructed by using modern communication channels is more advantageous than the image formed by traditional channels, whereas the indications "definitely not", "rather not" and "hard to say" were merged, treating people who gave such responses as one group of respondents disagreeing with this statement. The Cronbach Alpha test for the total number of the respondents had the value of 0.896, indicating high reliability. For respondents who agreed with the statement presented above, the value was 0.814, whereas for respondents with a different opinion it amounted to 0.799, which also indicates high reliability.
On the basis of the Kaiser criterion, for each of the three groups of respondents mentioned, three factors with eigenvalues greater than 1 were distinguished. They explain, in total, over 60% of the total variability of the system ( Table 2). The first factor, separated for all respondents, has an eigenvalue of 4.423 and explains almost 30% of variability. It includes 4 activities undertaken by employers, in the case of which the factor loading exceeded the 0.7 limit value adopted during the factor analysis (Table 3). These are the same activities which received the highest average ratings, occupying the top positions in the hierarchy of activities, which, according to the respondents, had the greatest impact on shaping the positive external image of an enterprise as an employer. These are internal and external activities based on building knowledge capital. In the case of the respondents who believe that the employer's image created on the basis of modern communication channels is more beneficial than the employer's image built by means of classical marketing communication channels, the first of the factors separated has a slightly higher eigenvalue (4.709) and explains a greater part (31.393%) of the total variability of the system analysed. The factor consists of five variables reflecting the four activities which entered the first factor for the total number of the respondents, accompanied by an activity regarding the establishing and consolidating of contacts with academic communities. It can therefore be said that this factor is characterized by a broader subject range as compared to the first factor identified for the total number of the respondents, also including activities related to building the relational capital.
The internal structure of the first factor is entirely different for the respondents who stated that the image shaped by modern communication channels is not better than the image shaped by classical communication channels. This factor includes four variables referring to activities consisting in conducting promotional campaigns both by means of classical media and modern media, such as social media. It is worth adding that the eigenvalue of this factor is much lower. It also explains the lowest part of the total variability of the phenomenon studied.
As for the second factor identified for the total number of the respondents, it includes four variables analogous to the first factor identified for the respondents who deny the possibility of creating a more favourable external image of the employer thanks to modern communication channels. The second factor, distinguished for the respondents indicating that such an image is better, has a similar structure. On the other hand, the second factor identified in the case of the respondents who have a different opinion is created by two variables concerning the building of knowledge capital within the organization, and in its the environment. The third factor includes one variable for each of the groups analysed, which is the organization of free work experience. This is the same variable for the total of the respondents and for the respondents who claim that the external image of an employer is better if it is built using modern communication channels. However, in the case of people representing a different opinion in this matter, the variable forming the third factor is active participation in job fairs, which is a variable of a completely different nature. It is worth adding that four variables did not enter into any factor for each group of respondents under analysis.
The factors recognized can be identified with the respondent segments characterized by the same attitude towards actions undertaken by employers. It is clearly visible that the factors are analogous to the total number of the respondents and to the respondents believing that the image shaped using modern communication channels is better, whereas they are entirely different in the case of the respondents who have the opposite opinion in this respect. Therefore, it can be assumed that the attitude towards the image-based effectiveness of using modern communication channels is a feature that differentiates opinions on activities which affect the shaping of a positive external image of an employer. tot.-total number of respondents; y-persons who answered "yes"; n-people who answered "no".

Respondents' Differentiation Depending on Their Opinions on whether the Employer's Image Created on the Basis of Modern Marketing Communication Channels Is More Beneficial Than the Employer's Image Created on the Basis of Classical Marketing Communication Channels
In order to verify this assumption, the Kruskal-Wallis test was carried out. It turns out that a statistically significant difference can be distinguished in the case of nine out of fifteen activities analysed, for which the significance level is less than the 0.05 limit (Table 4). These include, among other things, activities that took up key positions in the hierarchy and were included in the first factor for the total number of the respondents and for the respondents who believe that the external image created through modern communication channels is better. Thus, it can be concluded that the hypothesis H1 turned out to be valid for respondents only for the nine actions mentioned. Table 4. Significance of differences between responses regarding actions undertaken by enterprises depending on respondents' opinions on whether the employer's image created on the basis of modern marketing communication channels is more beneficial than the employer's image created on the basis of classical marketing communication channels. However, in the case of activities involving promotional campaigns, statistically significant differentiation was found only for campaigns on social media of the Facebook type. This is confirmed by the conclusion drawn from the results of the factor analysis. Activities of this type carried out in classical media were accompanied by promotional activities carried out in modern media. They were included in the same factor, regardless of whether it was about the total number of the respondents or for any of the other groups of the respondents analysed.
In the next stage of the analysis, dependencies between the respondents' opinions on the impact of activities undertaken by enterprises on shaping their positive external image as an employer and the respondents' opinions on whether the employer's image created on the basis of modern marketing communication channels is more beneficial than the employer's image created on the basis of classical marketing communication channels. As it results from Table 5, only five variables analysed have a significance level of less than 0.05. Therefore, only for these five variables can one talk about statistically significant dependencies between the activities undertaken by employers and the respondents' opinions saying that the external image of an employer created on the basis of modern channels is better than the external image of an employer created thanks to classical marketing communication channels. The five variables do not include any of the two variables that reflect the organization of promotional campaigns in social media. Thus, it can be said that in the case of the respondents, research hypotheses H2 and H3 are not valid. The identified relationships are characterized by low strength, as evidenced by the value of V-Cramer coefficient for individual variables, which is lower than 0.3. It is worth noting that these variables were not included in any factor identified in the factor analysis. Table 5. Dependencies between respondents' opinions on the impact of activities undertaken by enterprises on shaping their positive external image as an employer, and respondents' opinions on whether the employer's image created on the basis of modern marketing communication channels is more beneficial than the employer's image created on the basis of classical marketing communication channels.

Variable
Chi At the end of the analysis, it was checked whether respondent's age is a feature differentiating respondents' opinions about activities undertaken by enterprises which affect the shaping of a positive external image of an employer. The results of the Kruskal-Wallis test indicate that statistically significant differences occurred in the case of eight activities, which is indicated by the value of the significance level of less than 0.05 (Table 6), yet none of the two activities consisting in organizing promotional campaigns on social media. It means that for respondents the statement presented in the research hypothesis H4 is not true in the case these both activities.

Discussion
Based on the research conducted, it can be concluded that the results obtained constitute a significant contribution to theory, especially in the area of building an employer's image by using modern forms of marketing communication with potential employees. The aspects of communication through social media between an enterprise and the participants of the external labour market have so far been analysed in relation to the search for employers and the self-presentation of candidates. These issues were examined, among others, by Chiang and Suen [105], who focused exclusively on one of the specialist media platforms, which is LinkedIn, and Adams [106], who compared the effectiveness of LinkedIn with the effectiveness of Facebook in the process of finding an employer and employees. Adams pointed out that the relative importance of LinkedIn is greater in recruitment activities. Other authors compared in general terms the application of profes-sional and non-professional social media in the process of not only recruitment but also selection [101,107], demonstrating that stronger reactions of candidates occurred in the case of using of professional media. Nikolaou [108] also drew attention to the differences between professional and non-professional social media, but he focused, similarly to Hallam [109] and Yokoyama [110], on the scope of information presented in the recruitment process, without examining the aspects of image. Other authors, including Stopfer and SGosling [111], studied social media, both professional and non-professional, with reference primarily to recruitment and selection activities, indicating their key importance in this respect.
On the other hand, the research results presented in this article indicate that in the case of image-related activities, the importance of social media of the Facebook type was comparatively greater (with a higher value of the average rating). In addition, imagerelated activities undertaken with the help of both types of social media were present in the same factor both for the total number of the respondents and for the other two groups of respondents, which shows that the respondents who noticed the usefulness of taking actions in this area via Facebook also saw the usefulness of analogous actions taken via LinkedIn.
The results of the research presented in this article indicate that the age of the respondents was not a feature that statistically significantly differentiated the responses both in the case of professional and non-professional social media. However, other authors [101] did not find such differentiation in the case of using professional media in recruitment and selection activities, yet they identified differentiation in relation to the application of non-professional social media in the recruitment and selection process, which is a clear difference compared with the application of social media for image-related purposes.
Moreover, research on the attitudes and emotions of potential employees in the role of candidates for work has been conducted so far, but these studies were mainly limited to the perception of the recruitment process itself [112,113] and the tools and methods used in the process (the so-called 'Chan and Schmitt model') [114]). The perception of an employer reflected in the employer's external image has not been taken into account. In contrast to the studies mentioned above, in which differences in the perception of the recruitment process itself were identified, depending on the tools used during the recruitment process, this article did not recognize statistically significant dependencies between the use of professional social media and the external image of an employer. Such dependencies were not identified for non-professional social media, either, although in their case one can speak of statistically significant differentiation of responses among the respondents who believe that the employer's image created on the basis of modern channels is more beneficial than the employer's image created through classical marketing communication channels and the responses among the respondents with a different opinion in this matter. It is worth emphasizing that in the case of energy companies, only a few studies on employer can be mentioned. It should be emphasized, however, that they concerned the other aspects than shaping external employer's image by using social media. For example, Heilmann, Saarenketo and Liikkanen [29] studied the motives and practices of energy companies in the scope of employer branding.
Among the few studies referring to the perception of an enterprise using social media in the recruitment process, research conducted by Priyadarshini, Kumar and Jha [115] can be mentioned. The research showed that the use of social media leads to the perception of an enterprise in a positive light, yet the use of professional and non-professional media was not compared in these studies, treating social media as one group of forms of communication with candidates. In addition, that research was limited to analysing the statements of representatives of this group of participants of the external labour market, that is, the candidates. It had the nature of qualitative research, which made it impossible to conduct statistical analysis.
Therefore, it can be concluded that in the literature on the subject, as regards the relationships between potential employees and the employer, considerations regarding social media are carried out primarily in relation to the recruitment and selection process, and, for example, the image-related aspects presented in this article are omitted. Among the benefits obtained through the use of social media, image-related issues are often neglected, limited to the issues related to better and faster recognition of candidates [116], etc. Although some authors notice the fact that using social media poses new challenges for employers, such as the formation of reputation [110,117] or branding [118] which is close to the issue of image, they do not examine those aspects in detail in the context of image.

Conclusions
The purpose of the research conducted was to determine the importance of using modern marketing communication channels in the process of shaping the external image of an enterprise as an employer. The analysis covered fifteen activities undertaken by enterprises in the area of building their image as an employer, taking into account the views of the respondents on whether an employer's image created on the basis of modern marketing communication channels (e.g., Internet, mobile applications) is more beneficial than an employer's image based on classical marketing communication channels (e.g., press, television, radio). The results of the research indicate that organizing promotional campaigns on social media took a lower position, especially in the case of professional media. A relatively higher rating was obtained in the case of non-professional media, although it was only 9th position.
Among the total number of respondents, a segment of people who consider that undertaking communication activities in traditional and modern media influences the shaping of a positive external image of an enterprise as an employer was distinguished. This segment was also identified among the other two groups of the respondents. However, no segment was identified for people who would attribute an image-creating role only to modern media and to the use of modern media in promotional campaigns.
Statistically significant differentiation with regards to opinions on whether an employer's image created through modern media is better was identified for non-professional media but neither in the case of professional media nor non-professional media age of respondents was a differentiating feature. Thus, as the main conclusion it can be said that hypothesis H1 turned out to be valid for non-professional media like Facebook, and hypothesis H4 turned out to be invalid for both types of social media.
The next important conclusions concern the assumed dependencies. Statistically significant dependencies were not identified either for professional media or for nonprofessional media between respondents' opinions on the impact of activities undertaken by enterprises to shape their positive external image as an employer and respondents' opinions on whether an employer's image created on the basis of modern marketing communication channels (e.g., Internet, mobile applications) is more beneficial than an employer's image created on the basis of classical marketing communication channels (e.g., press, television, radio). It means that for activities connected with organizing promotional campaigns in social media in the case of the respondents, research hypotheses H2 and H3 are not valid.

Implications, Limitations and Directions of Future Research
The results of the research conducted and the conclusions drawn on their basis have a cognitive and application value, allowing the cognitive research gap identified to be reduced. The managerial implications include, for example, the fact that the use of classical and modern compositions of social media is a better solution in building a positive image of an enterprise as an employer, rather than relying solely on one or the other group of media, especially in the case of segments of respondents expressing such expectations. From the point of view of shaping a positive external image of an employer, activities leading to increasing knowledge resources among both current and potential employees by an enterprise are of key importance. Internship, training and work experience (especially paid), as well as the presentation of an individual offer in secondary and higher schools, obtained average ratings of the highest values. Conclusions drawn from the research have particularly big implications for executives and managers of energy companies too. They allow to prepare and conduct appropriate activities in the employer's image field increasing competitiveness of energy companies on the labour market as well as leading to sustainable development. It is very important because energy enterprises should recruit and retain the best specialists, which can be achieved by applying modern solutions in the marketing communications process, including communication via social media.
The results of the research have also social implications, indicating the attitude of potential employees to selected activities undertaken by enterprises in the field of personnel policy and the image-related importance of those activities.
Obviously, the research conducted has some limitations, which include its subjective scope (the research included only adults under 45 years of age), its objective scope (only selected aspects of using social media in shaping the external image of the enterprise as an employer were studied) and its geographical scope (the research included only Polish representatives of young potential employees). In future research, the authors will strive to eliminate those limitations by expanding the subjective, objective and geographical scopes of the research. It is worth emphasizing that although the limitation listed on the first position is an intentionally made assumption (respondents represented the socalled mobile age), in the future, authors want to conduct studies among representatives of other age groups. This will allow, among others, a comparative analysis to be made between representatives of different generations of potential employees and between representatives of various cultural circles illustrating the system of values from various countries. Moreover, it may also be interesting to undertake research on the impact of the COVID-19 pandemic on employer's image in the context of using social media for its creation.