The findings of this study are supported by other researches. Dobele, Toleman and Beverland (2005) and Ferguson (2008) analyzed, through case study research of some of the most successful viral marketing campaigns, the consumers’ responses to viral marketing stimuli in terms of brand awareness and attitudes and motivations regarding the brand.

Ferguson (2008) explored consumers’ responses to eight real life campaigns of well-known multinational companies such as Lego, Dell, Burger King, Dunkin’ Donuts and Procter and Gamble. He interviewed the marketing directors of these companies and the head managers of the online advertising agencies which conducted the viral marketing campaigns. The conclusions of this study are as follows:

• Viral marketing strategies are extremely useful to build brand awareness (e.g.: Burger Kings’ subservient Chicken was seen by 20 millions people).
• Viral marketing campaigns encourage word of mouth which, consequently, leads to trial and acquisition.
• Viral marketing strategies can be used to build effectively consumer loyalty. Viral marketing campaigns may be used to promote loyalty programs.

Dobele and her colleagues (2005) analyzed seven viral marketing campaigns released by international companies as Honda, Pepsi, Sony and Procter and Gamble. They attempted to identify the strategies behind the success of these campaigns and their effects on consumer behaviour.

These researchers concluded that viral marketing campaigns have a significant influence in changing the consumers’ brand image and positioning and increasing trial. They explained this influence by the voluntary nature of forwarding messages which is perceived favourably by the receivers and, consequently, it leads to positive attitudes towards the brand.

References

Dobele, A., Toleman, D., and Beverland, M., 2005. Controlled infection! Spreading the brand message through viral marketing. Business Horizons. 48, pp. 143—149

Ferguson, R., 2008.  Word of mouth and viral marketing: taking the temperature of the hottest trends in marketing. Journal of Consumer Marketing. 25(3), pp. 179-182

The values of this table indicate the order of importance of the source of the viral marketing message. The most important sources are strong-tie sources such as friends and family. On the other hand, weak-tie sources such as companies and unknown people are ranked in the last positions by the respondents. Friends (0.72) are the most important source in order to open an email. They are followed closely by relatives (0.92). Colleagues (1.66) are the third most important source to open an email according to the respondents. Organizations and companies are placed fourth (2.73) and unknown people are the least important source in order to open an email (3.98).

My analysis of the influence of the sources of the viral marketing messages are mainly based on the investigations of Bruyn and Lilien (2008) and Crutzen and his colleagues (2008).

Bruyn and De Lilien (2008) analyzed the influence and effects of viral marketing. They undertook an experiment in which 5134 business students from a US university initiated a chain of e-mails. Researchers invited the students to send an e-mail-based referral to one of their acquaintances, inviting them to participate in the study. The response rate of this experiment was 14%, and the average completion rate reached 25.8%.

They analyzed the influence of the source of viral marketing messages on the receivers of viral marketing communication. They concluded:

• The tie strength. Strong ties have a powerful influence in increasing awareness
• Perceptual affinity. Personal sources, considered by the consumers as similar to them, help to generate interest about the viral message
• Source expertise. Sources perceived by the consumers as experts on a specific area are not specially revelevant in order to influence consumer buying decisions.

Crutzen and his colleagues (2008) studied the persuasion power of the source of the viral marketing message taking into account different variables such as: type of relationship (friends, colleagues and relatives), gender, age and strength of the argument of the viral message. They developed an experiment which involved 236 university students of 18 to 24 years.

The conclusions of this investigation were as follows:

• There is not any interaction or main effect regarding gender.

• The invitation of a friend was more effective than any other source to attract young adults (18-25) to an Internet-delivered intervention.

• The strength of the argument used in the viral message is not as relevant as the source that sends the message.

• Viral marketing messages are more effective when they include an incentive.

References

Bruyn, A.,  De Lilien,  G., L., 2008.A multi-stage model of word-of-mouth influence through viral marketing. International Journal of Research in Marketing. 25 pp 151–163

Crutzen, R., de Nooijer, J., Brouwer, W., Oenema, A., Brug, J., and de Vries, N., 2008. Effectiveness of online word of mouth on exposure to an Internet-delivered intervention. Psychology & Health. 99999, pp. 1-11

The findings of this research point out that the type of email message which is most susceptible to go viral is videos. Although viral videos (including adverts) are not the type of message most received, they are the kind of email which is most forwarded. Moreover, YouTube and other broadcast sites ease the diffusion of this type of message which does not require any special attachment, only the link to the broadcast site where the video is posted.

Jokes are the second type of email messages most received and most forwarded. This second position may be due to the email contents most likely to be opened: funny and entertaining messages.

Corporate messages are by far the type of email most received by the Internet users. In addition, they are ranked in the third position in order of preference to be forwarded. Corporate emails may contain important information to the receivers; thus, it explains why they are frequently spread through the Internet.

They found that messages that spark strong emotions -humour, fear, sadness, or inspiration- are likely to be forwarded. Emails which contain information and relevant data about important events (warning, crime), and good causes are frequently forwarded and, also, opened by the receivers.

Other findings of this study were the principal reasons why people send emails. These researchers classified the reasons why consumers pass along emails into four categories: enjoyment and entertaining, relax, keeping in touch with people and helping other people.

Based on the findings of Phelps and his colleagues I undertook a research on consumers motivations to forward email messages. I carried out a survey  to evaluate how consumers rate the content of the emails in order to pass along these messages.  The results of this survey are as follows:

The chart above indicates the order of preference of the email contents according to the respondents of the survey. Emails perceived by the respondents as ‘important’ are the most likely to be opened. The second email content most likely to be opened is ‘funny’ emails, which are followed very closely by entertaining emails (third). ‘Helpful’ emails are ranked by the respondents as the fourth type of content most likely to be opened. The fifth email content most likely to be opened is ‘exciting’ emails. Finally, ‘relaxing’ emails are ranked by the respondents as the last type of email contents in order of preference.

References:

Phelps, J., E., et al, 2004. Viral Marketing or Electronic Word-of-Mouth Advertising: Examining Consumer Responses and Motivations to Pass Along Email. Journal of advertising research. December, pp. 333-348

Helm (2000 p.159) defines viral marketing as “a communication and distribution concept that relies on customers to transmit digital products via electronic mail to other potential customers in their social sphere and to animate these contacts to also transmit the products”. She stated that viral marketing is a marketing communications tool which may build word of mouth.

Modzelewski, on the other hand, argues that viral marketing differs from word-of-mouth in the value of the virus to the original consumer which is directly related. The message is not altered during the communication process because it is spread from person to person exactly how it was designed by the sender.

In 2006, Kirby and Marsden (2006) set up clearly the boundaries between word of mouth and viral marketing. They studied the different types of connected marketing (buzz, viral marketing, word of mouth marketing, etc.) and explained the differences among them. Kirby and Marsden (2006) define viral marketing and word of mouth as follows:

“Viral marketing is the promotion of a company or its products and services through a persuasive message designed to spread, typically online, from person to person”.

“Word of Mouth is the promotion of a company or its products and
services through an initiative conceived and designed to get people talking
positively about that company, product or service”.

These definitions are extremely useful to clarify the boundaries between these concepts. Whilst viral marketing is focused on how the company message is spread to the audience, WOM is intended to promote that people talk positively about product or brand in order to change or reinforce consumers’ attitudes and behaviours.

Ferguson (2008) goes further and distinguishes between viral marketing and word of mouth as cause and consequence. He argues that while WOM embraces all interpersonal communications in which is included the Internet; viral marketing has developed as a critical electronic extension of WOM, which is intended to build awareness and cause positive word of mouth.

References
Ferguson, R., 2008.  Word of mouth and viral marketing: taking the temperature of the hottest trends in marketing. Journal of Consumer Marketing. 25(3), pp. 179-182

Helm, S., 2000. Viral Marketing – Establishing Customer Relationships by ‘Word-of- mouse’. Electronic Markets. 10 (3), pp. 158–161

Jurvetson, S., and Draper, T.,1997.  Viral Marketing. [Online] Available from: http://www.dfj.com/news/article_26.shtml (accessed on 15  June 2009)

Jurvetson, S., 2000. From the ground floor: What exactly is viral marketing? Red Herring Communications. May, pp. 110-111

Pastore, M., 2000. The Value of Word of Mouth. Available at: http://adres.intemet.com/ feature/article/0,1401,8961_395371,00.htm, Accessed on June 4th  2009
Modzelewski, F.,M., 2000. Finding a Cure for Viral Marketing. Direct Marketing News. September (11)

Kirby, J. and Marsden, P. 2006. Connected Marketing: the Viral, Buzz and Word-of-mouth Revolution. 1st Edition. Oxford, UK: Butterworth-Heinemann

Kiecker, P., and Cowles, D., 2002.  Interpersonal Communication and Personal Influence on the Internet:A Framework for Examining Online Word-of-Mouth.Journal of Euromarketing.11(2), pp. 71-88

Viral marketing as virus can be spread according to two archetypes: densely knit groups and ramified networks (Boase and Wellman 2001).

Viral Communication Model

In densely knit groups, most members know each other, are in frequent contact with each other, but they have little contact with outsiders. On the other hand, in ramified networks few members are in contact with each other and a large portion of interactions are with outsiders. Viral marketing messages can be spread across a small group of people, in which members are closely bounded, or several groups of people which maintain weak ties.

References

Boase, J., and Wellman, B., 2001. A Plague of Viruses: Biological, Computer and Marketing. Current Sociology. 49(6), pp. 39-55

Johnson Brown and Reingen (1987) examined, from an interpersonal network perspective, the role that tie-strength may play in WOM processes. They concluded that strong-ties sources such as close relatives or friends are from whom most people obtain information. They also claimed that the role of weak-ties sources is not as important as it was though.

Herr, Kardes and Kim (1991) investigated the mediation of WOM effects on consumer’s persuasion. They attempted to identify additional moderating variables which may influence the degree of persuasion of WOM on the audiences. The results of their investigation indicated that WOM communications often have a strong impact on product judgments because information received in a face-to-face manner is more accessible than information presented in a less vivid manner.

Dunhan and his colleagues (1997) supported the findings of Herr, Kardes and Kim and added new information about other factors which affect word of mouth communication. They concluded that the likelihood of choosing strong-tie sources is influenced by task difficulty and prior knowledge, and the likelihood of choosing weak-tie sources is influenced by the importance of instrumental cues and subjective prior knowledge.

Figure : General Model of Recommendation Source Choice

Source: Duhan et al. 1997

Word of mouth plays an important role in influencing consumer attitudes and, consequently, affecting consumer choice, loyalty and brand switching (Wangenheim and Bayon 2003). Wangenheim and Bayon (2003) studied how WOM influences switching decisions. They concluded that expertise and similarity have an effect not only on perceived influence and attitudes, but also on subsequent decision making.

In an attempt to explain the key determinants of persuasion power of word of mouth and how WOM influences consumers’ attitudes and perceptions, behaviours Sweeney, Soutar ad Mazzarol (2008) developed the following model:

Figure: Model of WOM impact

Source: Sweeney, Soutar and Mazzarol 2008,

The personal attributes of the sender and the receiver, the type of relationship between them (tie strength, homophily), the message characteristics and the situational characteristics where this form of communication is developed, affect the way the word of mouth message is perceived by receivers. The degree and the nature of the word of mouth influence determine consumer’s perceptions, attitudes, beliefs and motivations towards the product or brand.

References

Dichter, E.,1966. How Word of Mouth Advertising works. Harvard Business Review. 44(6), pp. 147-161

Dichter, E.,1966. How Word of Mouth Advertising works. Harvard Business Review. 44(6), pp. 147-161Sweeney, J., C., Soutar, G., N., and Mazzarol, T., 2008. Factors influencing word of mouth effectiveness: receiver perspectives. European Journal of marketing. 42(3/4), pp. 344-364

Johnson Brown, J., and Reingen, P., H., 1987.Social Ties and Word-of-Mouth Referral Behavior. Journal of Consumer  Research.14 (Diciembre), pp. 350-362

Herr, P., M., Kardes, F., R., and Kim, J. 1991.Effects of Word-of-Mouth and Product-Attribute Information on Persuasion: An Accessibility-Diagnosticity Perspective. Journal of Consumer Research. 17(March), pp 454-462

Duhan, et al.1997. Word-of-Mouth Recommendation. Journal of the Academy of Marketing Science.25(4), pp. 283-295.

Lazarsfeld and Katz (1955) investigated the role of the personal influence in the daily household purchase decisions. They found that members of interpersonal communication networks (family, friends and colleagues) were the most important source of influence in the purchase of household goods and food products. They concluded that personal influence, which was called later “ word of mouth” by Ditcher (1966) and Merton (1968), was seven times as effective as newspapers and magazines, four times as effective as personal selling, and twice as effective as radio advertising in influencing consumers to switch brands.

Merton (1968) was one of the first authors who coined the term word of mouth communication. He defined this concept as a process of personal influence, in which interpersonal communications between a sender and a receiver can change the receiver’s behaviour or attitudes. The influence of personal sources as friends, relatives or colleagues plays a fundamental role in affecting perceptions and attitudes.

Since the 1960s several studies have documented the importance and determinant influence of word of mouth on consumer behaviour . Customers pay more attention to word of mouth because it is perceived as a reliable source of information. The senders of the message (friends, relatives, colleagues, etc.) are seen by the consumer as having no self-interest in promoting a product or a brand.

Nowadays, new technologies such as mobile phone and Internet have changed the scenario where the interpersonal communications are developed. This new scenario requires a more comprehensive definition as the one provided by The Word of Mouth Marketing Association: “The act of a consumer creating and/or distributing marketing-relevant information to another consumer”. This is more suitable definition of the concept of word of mouth in the current context.