Over the past decade, the networked information environment has increased consumers’ autonomy and brought radical change to the advertising industry. Now individual consumers can reach millions of others around the world and advise them on well-known brands through home-produced video-ads, which was not as accessible in a previous era dominated by one-way marketing. The overall objective of this thesis was to examine the attitudinal, behavioural and recall effects of consumer-generated advertising (CGA) on viewing audiences. This was achieved by implementing an exploratory sequential mixed method design. During an initial qualitative phase with focus groups, seven determinants of CGA effectiveness were identified: recognition of consumer-generated advertising; advertising quality; product involvement; perceived expertise of ad creators; motivations of ad creators; scepticism towards CGA; and consumer’s creativity. The Salience-Involvement model of CGA effects was then developed and tested in two subsequent empirical studies. Study One used a 2 x 2, between-subjects experimental design in which levels of advertising Source Salience (consumer-generated vs. company-generated) and Product Involvement (low vs. high involvement) were manipulated. Results reveal a largely negative impact of salient CGA when the consumer source was not disclosed. However, under high involvement conditions, amateur CGA was more entertaining and more likely to be electronically shared with others. Meanwhile, under low involvement, brands from consumer-generated ads showed higher levels of recall. Study Two investigated how the outcomes of professional and amateur CGA change after source disclosure using a 3 x 2 x 2, between-subjects design. In this experiment, levels of Source Awareness (consumer-generated ads vs. company ads vs. no source indicated) were manipulated in addition to Source Salience and Product Involvement. Findings show that Source Awareness produces an interactive effect with Source Salience and Product Involvement, which is significant only on the Cognitive component of Attitude towards the ad and the Attractiveness component of Credibility. Thus, disclosure of consumer source is likely to enhance ad evaluations when the CGA is professionally produced and involvement is low. Meanwhile, attribution of amateur CGA to consumer source is likely to have a negative impact. Conversely, attribution of an amateur ad to company source has a favourable attitudinal effect under high involvement. In summary, this research demonstrates that in the context of CGA, the communicator-receiver similarity does not necessarily guarantee a positive response. Most importantly, the CGA’s outcome is moderated by Source Salience. Since Source Salience specifically characterises the consumer source in this context, it could potentially add another dimension to the traditional conceptualisation of the information source.

This survey focuses on the attitude of the consumers towards a particular brand (Starbucks) and their intention to buy before and after their exposure to consumer generated advertisements. These advertisements include both positive and negatives messages using only verbal arguments. / Αυτή η έρευνα επικεντρώνεται στη στάση των καταναλωτών προς μια συγκεκριμένη μάρκα (Starbucks) και την πρόθεσή τους να αγοράσουν πριν και μετά την έκθεσή τους σε διαφημίσεις που δημιουργούνται απο καταναλωτές. Αυτές οι διαφημίσεις περιλαμβάνουν τόσο θετικά οσο και αρνητικά μηνύματα χρησιμοποιώντας μόνο λεκτικά επιχειρήματα.

This study examines the potential influence of consumer generated advertising on consumer’s trust in brands. In particular it focuses on consumer’s behavior before and after their exposure on consumer generated videos, which share their product experience (positive & negative). The study begins with a detailed literature review of previous academic research and theory. From this emerged the research objective and aims. Two different questionnaires were given to students and graduate students, before and after their exposure to consumer generated videos, so as to explore their influence to them. Interesting results and insights are presented, which represent the need for companies to gain a deeper understanding of the potential power of social media and consumer generated advertising and how it may be harnessed. / Η μελέτη αυτή εξετάζει την πιθανή επιρροή της διαφήμισης που παράγουν οι καταναλωτές απέναντι στην εμπιστοσύνη τους στις ευρέως γνωστές μπράντες. Συγκεκριμένα εστιάζει στην συμπεριφορά του καταναλωτή πριν και μετά την έκθεσή τους σε βίντεο (θετικά & αρνητικά) με εμπειρίες καταναλωτών σε διάφορα προιοντα. Η μελέτη ξεκινά με θεωρία σχετικά με τα social media απ'όπου προκύπτουν και οι αντικειμενικοί στόχοι της εργασίας. Συνεχίζει με το εμπειρικό κομμάτι όπου 2 διαφορετικά ερωτηματολόγια δίνονται σε καταναλωτές για να συμπληρωθούν, το πρώτο πριν από την προβολή των βίντεο και το δεύτερο μετά την προβολή ώστε να εξετάσουμε την πιθανή επιρροή στη συμπεριφορά τους. Τα ευρήματα είναι πολύ ενδιαφέροντα τόσο για τους καταναλωτές και τα ανερχόμενα social media όσο και για τις εταιρείες και τα προϊόντα τους.

This study explores how consumer’s attitudes towards consumer-generated advertising (CGA) have changed over time. The study measures consumer attitude changes of the winning contributions from Doritos Crash the Super bowl between the years 2007-2014 on YouTube. The study conducted in total 995 comments that was analysed with Leximancer Software, a research tool for making content analysis to determining the presence of words or concepts in collections of textual documents. Findings didn’t show a distinct change of consumer’s attitudes towards CGA over time. The study gave extended knowledge about consumers attitudes towards CGA and what factors that contribute to positive attitudes towards CGA. Were three main factors was notice, first, the fact that they managed to do an ad on a very low budget seemed to impress other consumers. Second, consumers had a tendency to defend CGA when the ad was criticized. Third, the fact that a company did not make the ad was impressive for many of the viewers.