How personality plays a role in affirming the self in the field of health behaviours and advertising

How personality plays a role in affirming the self in the field of

health behaviours and advertising

Ivar Schot

Student number: 11877480 Master Thesis

Word count: 8.241

Graduate School of Communication

Master’s Program Communication Science

Supervisor: Nynke van der Laan, PhD.

29 June 2018

Abstract

Self-affirmation as a resistance neutralizing strategy in the field of changing health behaviours has been proven to have promising effects. Yet, in the field of advertising this strategy is only proposed (Fransen, Verlegh, Kirmani, & Smit, 2015) and if personality traits as Extraversion remained to be uninvestigated. In an experiment (N = 150), the effects of self-affirmation on openness and intention regarding health and advertising messages, and if this effect is moderated by the level of extraversion of individuals are tested. Also, it is been examined if use of resistance strategies plays a mediating role in this. Results reveal that self-affirmation does not lead to more openness and intention, and that this effect was not moderated by level of extraversion. Furthermore, use of resistance strategies did not have effect on the relation between openness and intention after self-affirmation. Additionally, it has been found that consumers apply different strategies regarding different persuasive messages. Nevertheless, it could not be confirmed that self-affirmation can have promising effects in the field of

advertising as proposed. Therefore, it cannot be concluded that self-affirmation has an effect on individuals openness and intention when facing persuasive messages, and if this is moderated by people’s personality traits as extraversion.

Introduction

Persuasion is often used to convince people to change their behaviour. For example, changing to a healthier lifestyle as promoted by a health campaign, or to buy certain products via advertisements. However, this has led to consumers experiencing evoked feelings of

resistance which is followed by less openness towards persuasive messages (Knowles & Linn, 2004). Persuasion naturally evokes resistance of consumers whom feel intruded in their freedom of choice (Jacks & O’Brien, 2004), resulting in the evolutionary response resistance which protects our self-concept from being harmed (Friestad & Wright, 1994). Next to that, resistance is a motivational construct of consumers who are not willing to change in an attitudinal and behavioural matter (Knowles & Linn, 2004). Nevertheless, even with this resistance to persuasion, marketers aim to persuade the consumers. Taking this into account, Fransen, Verlegh, Kirmani, and Smit (2015) proposed that when facing advertisements consumers use different resistance strategies. These include: avoidance of the persuasive attempt, contesting the persuasive attempt, or empower the self on beliefs and attitudes regarding the attempt. To overcome, for example, empowerment strategies of consumers, self-affirmation is a resistance neutralizing strategy that addresses resistance indirectly through reducing the need of being resistant, in which it forms a buffer between the self and the persuasive message (Jacks & O’Brien, 2004; Sherman & Cohen, 2002, 2006). By reducing the need to be resistant, affirming the self leads to a more open-minded appraisal of the persuasive message (Sherman & Cohen, 2006) , and will thus lead to more openness towards a persuasive message (hereby referred to as ‘openness’)(Jacks & O’Brien, 2004).

When analysing self-affirmation interventions in a broader perspective, it has shown promising effects. In the domain of health, recent meta-analytic research showed that self-affirmation reduces the resistance against persuasive health messages caused by an increase in message acceptance and intentions to change, making subsequent behaviour change more

likely (e.g. smoking behaviour, screening behaviour) (Epton, Harris, Kane, van

Koningsbruggen, & Sheeran, 2015). In one study, undergraduates acknowledged the risk of HIV when having sex more after a presented educational video due to affirming the self, which resulted in purchase intention and actual buying of condoms (Sherman, Nelson, & Steele, 2000). In the same study, it was found that female coffee drinkers who were at risk for fibrocystic breast disease, intended to drink less caffeine due to greater message acceptance after self-affirmation (Sherman et al., 2000). These effects of self-affirmation were confirmed in different experimental studies on several health behaviours, such as the intention to change behaviour in reducing alcohol consumption (Harris & Napper, 2005), health screening

behaviour (Howell & Shepperd, 2012; Van Koningsbruggen & Das, 2009), quitting smoking behaviour (Harris, Mayle, Mabbott, & Napper, 2007), and sun protection intentions (Good & Abraham, 2011; Schüz, Schüz, & Eid, 2013). Next to the intention of changing behaviour, self-affirmation affected also actual behaviour change in fruit and vegetable intake (Epton & Harris, 2008), and reducing alcohol consumption (Scott, Brown, Phair, Westland, & Schüz, 2013). Yet, since self-affirmation showed promising effects in de domain of health

behaviours, effects of self-affirmation are only hypothesized in the field of advertisement by Fransen and colleagues (2015b). Thus, the usability of self-affirmation to increase openness and intention to perform the advocated behaviour (hereby referred to as ‘intention’)

considering advertising, is still not examined. Therefore, this study will try to conduct evidence on people’s openness and intention when facing advertisements.

Another influencing factor regarding people’s openness towards advertising can be people’s personality traits. According to Hirsh, Kang, & Bodenhausen (2012) tailoring of advertisements based on peoples personality traits is one solution to increase more favourable evaluations of advertisements of consumers. The assumption can be made, that personality plays an influencing role in approaching and evaluating advertisements (Hirsh et al., 2012;

Stysko-Kunkowska & Borecka, 2010). According to the ‘Big Five’ factor model of McCrae and Costa (1987) behaviour and mindset differ depending on where consumers are located on the spectrum of personality traits. This study will focus on the personality trait Extraversion. Extraverts are more associated with positive feelings evoked by ads than introvert, and contain a more positive attitude regarding advertisements in general (Mooradian, 1996). According to recent research, high levels of extraversion also predict a favourable attitude towards online advertisements (Souiden et al., 2017).

Another contribution to the literature shows that recruitment advertisements that were tailored towards the personality of potential employees (wording that described their

personality was either included or not), resulted in higher attractiveness of the advertisements for extravert participants in general (Stevens & Szmerekovsky, 2010). As a result, introverts reported a significantly lower attitude towards advertisements. Introverts might evaluate advertisements more negatively because they perceive the nature of advertisement as being intrusive, annoying, and irritating (Lee & Cho, 2010; Mord & Gilson, 1985; Speck & Elliot, 1997). A reason for this could be that introverts tend more to rely the focus on negativity in general (Baer et al., 2016; Chang, 2001). As they will start from a more negative point toward advertisement, affirming the self, if having an effect, will have more effect in comparison to the extraverts, as they are already more open to advertisements. This is backed up by recent research that has found that participants with high levels of extraversion were more willing to share sponsored content (i.e. sponsored advertisements) on Facebook (Clark & Çalli, 2014). Sharing advertisements is in line with the assumption that extraverts do not experience

advertisements as intrusively as introverts do, and thereby confirms the differences in attitude towards advertisements. Since introverts perceive persuasive messages such as advertising more negatively than extraverts, it can be assumed this has a negative effect on their openness and intention regarding this kind of messages.

A possibility to overcome this evaluation of intrusiveness, and more negative attitudes towards advertisements of introverts, could be self-affirmation. This outlines why different consumers use different resistance strategies when facing persuasive message. This study tries to address this resistance in which self-affirmation serves as a solution to overcome this. With various uses of self-affirmation in the domains of health behaviours, this study aims to present a solid foundation for a more detailed use of persuasion in the domain of

advertisement. According to the retrieved knowledge from other domains it’s possible that it has the same promising effects in the domain of advertisements, and it will lower resistance to advertisements by affirming the self. Thereby, it should provide clear argumentation that targeting persuasion based on personality traits, particularly introversion, can contribute to the effectiveness of advertisement. In line with above made statements, this study will attempt to answer the following research question:

RQ: What is the effect of affirming the self on one’s a) openness, and b) intention, towards a persuasive message and is this effect moderated by the level of extraversion?

Theoretical Framework Self-affirmation Theory

When people face persuasive messages that are not in line with their attitudinal predispositions, they activate the evolutionary response stated as resistance, which protects their self-concept from being harmed (Friestad & Wright, 1994). Defining resistance as a motivational state, it has been emphasized that it serves the goal of retaining peoples current attitude and to mitigate attitudinal or behavioural change (Knowles & Linn, 2004)

When talking about the resistance that persuasive health campaigns and advertising induce, it is proposed, in recent research, that self-affirmation is a resistance-neutralizing strategy that overcomes individuals’ resistance resulting in more openness (Fransen et al, 2015; Fransen et al., 2015). Self-affirmation can overcome feelings of interferes and conflict with peoples’ self, that persuasive messages can evoke (Jacks & O’Brien, 2004).

The fundamental foundation of the Self-Affirmation Theory, is that people are

motivated to be integer, and they want to maintain this integrity regarding their self (Sherman & Cohen, 2006; Steele, 1988), which resembles being morally correct and acting proper according to individuals’ salient beliefs (Sherman & Cohen, 2002). By affirming the self before a persuasive attempt, self-integrity of individuals is confirmed, in which they approach persuasive messages more open-minded (Sherman & Cohen, 2006). When affirming the self, this should happen on a topic that is highly valued by the recipient, yet unrelated to the persuasive message. Otherwise, self-affirmation will not form a buffer between the self and the persuasive message (Jacks & O’Brien, 2004, Knowles & Linn, 2004). The evoked response that induces resistance is subsequently neutralized by this buffer, mitigating recipients from the need to distort the provoking threat (Jacks & O’Brien, 2004). Boundary wise, if self-affirmation is evoked under awareness of participants it has significant less effect (Sherman et al., 2009). In sum, affirming individuals’ self will protect their self-integrity from

being harmed (Friestadt & Wright, 1994), such that self-affirmed people are more open towards persuasive messages (Sherman & Cohen, 2006).

When applying persuasion to the domains of health and advertising, campaigns are set up to change people’s behaviours. Either, these campaigns should persuade people to change health risk behaviours (e.g. smoking, alcohol, screening behaviour, healthy dietary), or persuade individuals intention, and to perform the advocated behaviour (i.e. advertising). When affirming the self of individuals in experimental health behaviour interventions, it proves to be successful in increasing the intention to change behaviour, as well as actual behaviour change. (Epton et al., 2015).

These effects of self-affirmation were confirmed in different experimental studies on several health behaviours, such as the intention to change behaviour in reducing alcohol consumption (Harris & Napper, 2005), health screening behaviour (Howell & Shepperd, 2012; Van Koningsbruggen & Das, 2009), quitting smoking behaviour (Harris, Mayle, Mabbott, & Napper, 2007), and sun protection intentions (Good & Abraham, 2011; Schüz, Schüz, & Eid, 2013). Next to the intention of changing behaviour, self-affirmation affected also actual behaviour change in fruit and vegetable intake (Epton & Harris, 2008), and reducing alcohol consumption (Scott, Brown, Phair, Westland, & Schüz, 2013).

Nevertheless, affirming the self of individuals has yet not been tested in the field of advertising. Fransen and colleagues (2015b) proposed, if advertisers would focus on enhancing consumers’ self-esteem, consumers would approach advertising more openly which can lessen the usage of resistance strategies. Research showed that affirming peoples’ positive self-view can explain why peoples’ perceptions of persuasive intent are reduced, and subsequently reduce evoked resistance (Dolinski, Nawrat, and Rudak 2001)

Therefore, since the effects of self-affirmation have not yet been examined in the field of advertising, this research will try to conduct evidence if self-affirmation can have the same

promising effects in the field of advertising as in the field of health behaviours. Since actual behaviour is hard to measure, this research will measure intention to perform the advocated behaviour as the dependent variable. Since intention is the strongest predictor of actual behaviour according to the widely applied Theory of Planned Behaviour (Conner & Sparks, 2005), this is considered as a valid choice. Thereby, recent research in the domain of health on self-affirmation prove several times to increase intention towards proposed health messages (e.g. fruit and vegetable intake, smoking behaviour, screening behaviour, alcohol

consumption) (Epton & Harris, 2008; Harris et al., 2007; Harris & Napper, 2008; Klein, Harris, Ferrer, & Zajac, 2011). Considering the prior, following hypotheses are proposed: H1a: Individuals whose self was affirmed will have higher openness towards a persuasive

message compared to individuals whose self was not affirmed.

H1b: : Individuals whose self was affirmed will have higher intention to act in line with a persuasive message compared to individuals whose self was not affirmed.

Extraversion

The main reason why people differ in attitudinal perception and forming different opinions on, for example, the daily 3000 advertisements we see each day is grounded in the divergent factors that explain the foundation of personality in individuals. The Five-Factor Model of personality (FFM) states that personality is formed by three core components, namely basic tendencies, characteristic adaptations, and self-concept, sub-component of characteristic adaptations. The basic tendencies that contribute to forming one’s personality are traits labelled as the ‘Big Five’, in particular, Extraversion, Neuroticism, Openness, Agreeableness, Conscientiousness. These traits are stable over time and influence, next to characteristic adaptions which represent intrapsychic and interpersonal features as expressions of these traits, directly the self-concept of individuals (McCrae & Costa, 1996). Additionally,

the FFM is completed by biological bases of individuals, objective biography of individuals (i.e. instance of behaviour), and external influences, which are not influenced by affirming individuals self.

According to the FFM, the distinct in personality traits leads to different subsequent attitudes and mental schemas which define different opinions, which can only be inferred from expressed experiences and real behaviours (Costa & McCrae, 1992). Taken individual differences into account, every individual is somewhere located on the continuum of all of these personality traits. When focussing on the personality trait of Extraversion, it is described as to what extent individuals feel comfortable of engaging with direct social interactions and outgoing behaviours (Costa & McCrae, 1992). Thereby, individuals that score high on Extraversion (i.e. extraverts) seek out to more sensation and prefer higher levels of intensity when, for example, receiving physical stimuli compared to introverts (Eysenck, 1967). Unsurprisingly, extraverts embed an higher threshold for experienced arousal (Zuckerman, 1979), which explains their label as ‘excitement seekers’ (Lee, Lee, & Hansen, 2017). In line with this finding, extraverts and introverts showed a different evaluation of situations and stimuli, such as advertising (Stysko-Kunkowska & Borecka, 2010). The seek for sensation which is experienced as an incentive, explains why extraverts are overall more attracted by, for example, recruitment advertisements regardless of the content that is embedded by the advertisement (Stevens & Szmerekovsky, 2010). This is in line with recent confirmation that favourable attitude towards advertising are moderated by the level of extraversion (Souiden et al., 2017).

Since the differences in attitude and evaluation of extraverts and introverts has been confirmed in recent research (Souiden et al., 2017; Stysko-Kunkowska & Borecka, 2010), this study is trying to conduct evidence on if the level of extraversion moderates effects of a self-affirmation intervention, on openness and intention of self-affirmed individuals when facing

persuasive messages. Since, introverts start from a more negative point towards

advertisement, affirming the self, if having an effect, will have more effect in comparison to the extraverts, due to their already high attitude towards advertisements. Clear argumentation for this can be retrieved from research that states that introvert experience advertising more as intrusive to the self (Lee & Cho, 2010; Mord & Gilson, 1985; Speck & Elliot, 1997).

Thereby, different then extraverts, introverts tend more to rely the focus on negativity (Baer et al., 2016; Chang, 2001), thus, also in advertisements. Therefore, it is assumed that affirming the self can have greater buffering effects for introverts on their self-integrity, which should induce a more open-minded approach as extraverts already do have.

In sum, by affirming the self, bolstering introverts pre-existing basic tendencies can thus directly prevent the self-concept from being harmed, and thus self-integrity from being threatened. In line with this, self-affirmation interventions could induce more openness and intention under introverts towards persuasive messages than under extraverts. Therefore, considering the prior, following hypotheses are proposed:

H2a: The positive effect of self-affirmation on individuals’ openness towards a persuasive message is moderated by the level of extraversion, such that when the effect is self-affirmation is stronger for individuals low (vs. high) in extraversion.

H2b: The positive effect of self-affirmation on individuals’ intention to act in line with a persuasive message is moderated by the level of extraversion, such that when the effect is self-affirmation is stronger for individuals low (vs. high) in extraversion.

Self-affirmation has proven to lower resistance of individuals when facing persuasion, resulting in an increase in people’s openness towards persuasion (Jack’s & O’brien, 2004). In other research self-affirmation led after more acceptance of the message and thus openness, to subsequently to more intention to several health behaviours after self-affirmation (Sherman et al., 2000). From this, it can be assumed that after self-affirmation people are more open towards a persuasive message due to an increase in message acceptance, which than lead to an increase of intention to perform the advocated behaviour (Sherman et al., 2000). To this extent, in this study it is hypothesized that self-affirmation thus lowers use of resistance strategies.

Research states that people’s when use of resistance strategies is high, this predicts lower intentions (Fransen et al., 2015a). When persuasion evokes resistance due to threatening self-integrity of individuals, and thus lowers openness, this will lead to use of a resistance strategy by individuals. Yet, in the field of advertising is only proposed that consumers choice of which resistance strategy will be used, depends on the nature of the persuasive message (Fransen et al., 2015a; Fransen et al., 2015b) According to Fransen and colleagues (2015b), these consumer resistance strategies can be defined as contesting, avoidance, and

empowerment. In this study, we hypothesize that use of a resistance strategy has a mediating effect on the relationship between openness and intention of individuals. It has been proposed in recent research, that due to this study in which a persuasive health message and general advertisement will be shown, concern of deception regarding the messages, empowerment of individuals beliefs regarding the message, ore avoidance of the message are the most relevant resistance strategies to take into account (Fransen et al., 2015b). Reasoning for this

assumption, is that health messages are related to a threat of freedom of recipients (Sherman & Cohen, 2006), since these messages propose behaviour change that is against the

deception can be more attributed to advertisements due to peoples sceptical evaluation and lack of trustworthiness of advertising (Obermiller & Spangenberg, 1998). On the latter, counter-arguing the persuasive elements of the message could be also a reason for concerns of deception (Jacks & Cameron, 2003). Last, avoidance of the message can occur when

persuasive messages do threaten individuals self-integrity to much, to protect the self from being harmed and eliminate the threat (Friestad & Wright, 1994), as in persuasive health messages (Sherman & Cohen, 2006) or advertising (Fransen et al., 2015). It is been

hypothesized that after-affirming the self, the need of using a resistance strategy when facing a persuasive message will be lower than in not affirmed individuals.

In sum, it is been proposed that different strategies are applied by consumers when approaching different persuasive messages. It is been assumed that openness is negatively correlated with expression of resistance strategies. Thereby, use of resistance strategies to their account have also a negative effect on intention to act in line with the advocated behaviour. Research showed that the level of openness towards a persuasive message has showed to have a direct negative effect on evoked resistance, and thus on use of resistance strategies (Jacks & O’Brien, 2004). To that extent, it is proposed that use of resistance strategies do negatively mediate the relationship between openness and intention to act line with the proposed persuasive message, which is retrieved from recent research (Fransen et al., 2015b). Therefore, the following hypotheses are applied:

H3a: Individuals’ openness towards a persuasive message has a positive relation on intention to act in line with a persuasive message.

H3b: Individuals’ openness towards a persuasive message has a positive relation on intention to act in line with a persuasive message, and this relation is further mediated by the use of resistance strategies, such that when the use of resistance strategies is high (vs. low) this effect gets weaker (vs. stronger).

Methods

Study Design

In order to answer the research question, the design of the proposed study was formulated as a 2 (Between-subjects) x 2 (Between-subjects) factorial design, with self-affirmation (self-self-affirmation vs. no self-self-affirmation) and extraversion (high vs. low) which was a quasi-experimental factor, as between-subjects factors. The main experiment was conducted via an online questionnaire spread through social media and it contained two conditions. During the experiment participants were either assigned to the self-affirmation condition or to the control condition (no self-affirmation). The control group was added to operationalize the experiment just as a true experiment and compare base line openness and intention.To enhance internal validity, participants were randomly distributed within one of the conditions.

Respondents

Participants were recruited via Facebook and LinkedIn, the minimum age for participants was 18, and participating in the pre-test was not allowed. A total of 150

participants performed the online Qualtrics questionnaire. Multiple participants were excluded from the experiment. Participants were excluded for not accepting informed consent (N = 9), for not entering demographics (N = 7), and not meeting the inclusion of being at least 18 years old (N = 5). The final sample for analyses contained 129 participants, in which 52.7% was male and 47.3% was female. Participants’ age ranged from 18 to 87 (M = 27.47, SD = 10.53). The participants’ highest level of education was University Master (32.6%), followed by University Bachelor (30.2%) The group of participants consisted of 20 different nationalities, mostly from the Netherlands (75.9%) and Germany (5.4%).

Procedures

Recruited participants were told that the research was investigating personal values and preferences regarding different personalities. Affirming the self was purposefully not mentioned because this would result in significant lower self-affirmation effects (Napper et al., 2009).

After providing informed consent, participants reported their self-esteem. Next, participants had to fill in three items regarding their general attitude towards advertisements. Then, participants were randomly distributed to either the self-affirmation condition or the control condition. Participants in both conditions completed a questionnaire developed by Napper and colleagues (2009) serving as self-affirmation manipulation and control

questionnaire. After this questionnaire, two persuasive messages which represented a general commercial advertisement and a health promotion message were shown in random order to both conditions. This was followed by six items regarding openness towards the messages and the intention to perform the advocated behaviour of the messages. After this, eight items retrieved from the Big Five regarding personality trait extraversion were scored by participants. Subsequently, to finish the experiment in the control condition, five items regarding participants’ current self-esteem were asked to measure self-affirmation effects and were measured on a self-affirmation scale. Finally, the self-affirmation condition was asked if they were aware of the self-affirmation manipulation during the experiment. After finishing the survey participants were debriefed about the purpose of the study and for which aim the self-affirmation condition was manipulated.

Materials

A pre-test was conducted in order to examine whether the stimulus materials, which

were specially designed for this study, were feasible to use in the main experiment. Thus, the health promotion message and the advertisement were perceived as moderately threatening to

the self-integrity of the participants. Recent research showed that self-affirmation could have backfire effects if the message is not persuasive enough (Klein, Harris, Ferrer, & Zajac, 2011). Due to this, confirmation was necessary because in case of a low self-threatening message, this would have reduced self-affirmation effects. Also, when the message would have been extremely self-threatening, the amount of elicited resistance could have led to avoidance of the message and this was not desirable for the present study (Fransen et al., 2015a).

A total of 18 participants (11 men, 7 woman), mostly under graduate master students were asked to rate the presented stimulus materials. Inclusion criteria for participants were a minimum age of 18 years and not participating in the main experiment. The age of the participants differed from 18 to 29 (M = 24.92, SD = 2.62) who were mostly Dutch (N = 16). Participants were recruited via the personal network of the researcher. No cultural differences were reported.

Participants of the pre-test were exposed to a health promotion message and a general advertisement, before they were asked to answer six questions regarding both messages. These questions represented attitude towards the message, message acceptance, openness and intention. Lastly, participants were asked to score both messages on reality and how the perceived them. After answering all questions, participants were debriefed about the purpose of the pre-test.

The stimulus materials consisted of a health promotion message of the World Health Organization (WHO) promoting to eat more fruit and vegetables, which was copied from research of Harris and Napper (2008), and a general ad from Bol.com displaying a mid-season sale incorporating message: ‘Grab your chances, mid-season sale! -50%!’. Findings revealed that persuasion was more pronounced by strong messages compared to weak messages

was highlighted explicitly on the health promotion message itself and before answering the questions regarding the message.

The presented advertisement and health promotion message were rated on a seven-point Likert scale which can be found in the Appendix (E & F). Additionally, since only openness and intention were relevant for this study, only results on these items are discussed. The health promotion message elicited moderate intention (M = 4.09, SD = 1.71) and elicited moderate openness (M = 5.09, SD = 1.56), so no changes had to be made. Furthermore, the ad elicited less than moderate intention (M = 2.81, SD = 1.68), and was eliciting moderate

openness (M = 3.95, SD = 1.99). Therefore, to increase participants’ intention to click on the ad, the message was made more attractive by raising the offer (i.e. -70%), and directed

specifically to the participant (i.e. only for you!). Lastly, the ad (M = 3.72, SD = 1.41) and the health promotion message (M = 3.94, SD = 1.39) were perceived on a five-point Likert-scale, anchored at 1 ‘not as real’ to 5 ‘yes as real’, as almost as real and were in sum usable for the main experiment.

Measures

Self-affirmation manipulation. The self-affirmation manipulation was developed by

Napper and colleagues (2009) which main constructs were: Wisdom and Knowledge,

Courage, Humanity, Justice, Temperance, and Transcendence. The 32 item long questionnaire was developed because other manipulations (e.g. writing an essay on important values) were time consuming, and did not have a high equivalent control task, in which the control

condition responds to the same items as in the self-affirmation condition. In the control questionnaire, instead of focusing on the values of the participants themselves, the items reflected participants thoughts regarding the values and strengths of King Willem Alexander. In the original questionnaire, the control condition responded to David Beckham, but since

most of the participants were expected to be Dutch, it was decided to choose a Dutch person which was not very controversial, such as King Willem Alexander.

Results showed significant positive effects with an average mean of .94 higher on a 0 to 6 scale comparing the self-affirmation manipulation to the control task (Napper et al., 2009). Thereby, a consequence of using this questionnaire was that affirming the self of participants did not need to be on an unrelated topic to be effective (Jacks & O’Brien, 2004).

Big Five Extraversion measure. To measure the level of extraversion, a Big Five

eight-item scale was adopted form research of Benet-Martínez and John (1998), which is also been used in research of Souiden and colleagues (2017). Example of the items that measured level of extraversion which can be found in Appendix C was: “I see myself as someone who is talkative”. All items were measured on a five-point Likert-scale anchored at 1 (strongly

disagree), 4 (neither agree nor disagree), to 7 (strongly agree). The combined means of these

items were used to score participants on the continuum of the personality trait extraversion. A median split was performed at 5.0 to divide participants in two groups. Participants with a mean score above 5.0 were labelled as ‘extravert’ (N = 58), participants with a mean score below 5.0 were labelled as ‘introvert’ (N = 48). The reliability of the scale for measuring level of extraversion was excellent, Cronbach’s α = .90.

Dependent variables

Self-affirmation effects were tested via two variables, namely openness towards a persuasive message and intention to perform the advocated behaviour by a persuasive message. Participants were asked to answer the items directly after the self-affirmation questionnaire.

Openness health message and Ad. The scale to measure openness towards the health

message and advertisement was composed out of two items, which were inspired from research of Jacks and O’Brien (2004), and can be found in Appendix B. The items were: “To

what extent do you feel resistant towards the message?” and “To what extent do you feel open towards the message?”. A PCA was conducted which demonstrated that only one component had an eigenvalue above 1 (E.V. = 1.68), which explained 84.18% of the total variance of the scale. Furthermore, the reliability of the scale for measuring openness was good, Cronbach’s α = .81 (M = 3.79, SD = 1.59).

Intention health message and Ad. The scale for measuring intention was composed out

of two items, which were retrieved from research of Napper and Harris (2008) and Gauzente (2010), which can be found in Appendix B. Firstly, regarding the health message, a PCA was conducted which resulted in the reliability of the scale for measuring intention was poor. Therefore, removing one item out of the scale resulted in Cronbach’s α = .61 (M = 4.72, SD = 1.29), which was sufficient. The used item was: “I intend to eat at least 2 portions of fruit and 250 grams of vegetables each day, in the next 7 days”. Next, regarding the general ad, a PCA was conducted which resulted in only one component that had an eigenvalue above 1 (E.V. = 1.89), which explained 94.24% of the total variance of the scale. Furthermore, the reliability of the scale for measuring intention was excellent, Cronbach’s α = .94 (M = 3.43, SD = 1.83). Example of the items was: “To what extent would you intend to click on the ad?”.

Self-esteem measure. The self-esteem scale which was used for the base line measure

and manipulation check was scored on a seven-point Likert-scale and was adopted from research by O’Malley and Bachman (1983) and Sherman and colleagues (2000). These items were derived because of measuring esteem and used in previous research on

self-affirmation manipulations. Example of the items was: ‘How do you currently feel about yourself?’ from the latter research (Sherman et al., 2000). The remaining items were derived from the former research, with examples of items being: ‘I feel I am a person of worth’ (O’Malley & Bachman, 1983). Since both scales were measuring self-esteem, a new consistent scale was created and both scales were combined into a seven-point Likert-scale

(Appendix C). A PCA was conducted which resulted in only one component that had an eigenvalue above 1 (E.V. = 3.46), which explained 69% of the total variance of the scale. Furthermore, the reliability of the scale for measuring self-esteem was good, Cronbach’s α = .88 (M = 6.93, SD = 1.28).

General attitude towards advertisements. The general attitude towards advertisements

scale included three items measuring participants’ general attitude towards advertisements. These questions were adopted from recent research of Dianoux, Linhart and Vnoučková (2014) and Souiden and colleagues (2017). Example of these items include: “Overall, I do like advertising” (Appendix A). The items had to be answered on a seven-point Likert-scale and were anchored at 1 (I totally disagree), 4 (I feel neutral), and 7 (I totally agree). These three items together measured participants’ baseline attitude towards advertisements. A PCA was conducted which showed that only one component had an eigenvalue above 1 (E.V. = 2.62), which explained 87.28% of the total variance of the scale. Furthermore, the reliability of the scale for measuring general attitude towards advertisements was excellent, Cronbach’s α = .92 (M = 4.02, SD = 1.46).

Manipulation check awareness self-affirmation

For the self-affirmation manipulation to be successful, participants had to be unaware that they were being manipulated (Sherman et al., 2009). Awareness of participants during the experiment would decrease affirmative effects. To check if participants were aware of the purpose of the self-affirmative questionnaire the following question was asked at the end of the experiment which can be found in Appendix D. After answering “yes” four options were provided in which answering “to affirm the self” led to exclusion of the sample. This

manipulation check was adopted from Sherman and colleagues (2009) which provided a list with 12 options for participants to rate if it had influenced their results. All other options and answering “no” on the former question led to inclusion into the final sample of the

experiment. Three participants were excluded due to being aware of the self-affirmation manipulation.

Results

Randomization

Chi-square tests showed that participants in the self-affirmation condition and the control did not differ significantly for gender Χ2(1, N = 118)= .00, p = 0.985, and education Χ2

(5, N = 118)= 7.20, p = 0.206. Also, an independent t-test indicated that participants’ age,

t(116) = .445, p = .657, 95% CI [-3.04, 4.80] did not differ among the conditions. In

conclusion, randomization on condition appeared to be successful, and none of these variables was included as covariate in further analyses.

Self-esteem. To analyse whether differences in level of self-esteem existed among the

different conditions at the beginning of the experiment, a one-way ANOVA was conducted. Levene’s F (1, 116 = 3.34, p = .70) showed no significant inequalities of distribution among the conditions. The ANOVA showed a significant difference in self-esteem F (1, 116) = 5.66,

p = .019, η2 = .047) between the self-affirmation condition (M = 5.56, SD = 1.07) and the

control condition (M = 5.02, SD = 1.38). Therefore, self-esteem at the beginning of the experiment was included as a covariate in the self-affirmation manipulation check, but not in further analyses because this would had have affected the effect of self-affirmation on the individuals intention and openness.

General attitude advertisements. A one-way ANOVA was conducted to examine

whether differences in general attitude towards advertisements between the self-affirmation and the control condition existed at the start of the experiment. Homogeneity of variance assumption had not been violated, Levene’s F (1, 116 = 3.42, p = .067). No significant differences were reported F (1, 116) = 1.32, p = .253, η2 = .011) between the self-affirmation condition (M = 4.18, SD = 1.29) and the control condition (M = 3.87, SD = 1.57). As an

additional check, a one-way way ANOVA was conducted to compare extraverts and introverts regarding their general attitude towards advertisements. The results showed no significant differences on general attitude towards advertisements were reported F (1, 114) = 3.48, p = .065, η2 = .030) between extraverts (M = 4.28, SD = 1.34) and introverts (M = 3.80,

SD = 1.49).

Manipulation check

Self-affirmation manipulation. To check if self-affirmation manipulation was

successful, a one-way ANOVA was used. Levene’s test F (1, 105 = 1.56, p = .215) was not significant. The difference found on the scale of self-esteem between the self-affirmation condition (M = 5.65, SD = .96) and the control condition (M = 5.35, SD = 1.27) was not significant, F (1, 104) = 0.12, p = .728, η2 = .001). Despite using a covariate to correct the significant difference in self-esteem between the self-affirmation condition (M = 5.56, SD = 1.07), and the control condition (M = 5.02, SD = 1.38) at the beginning of the experiment, the self-affirmation manipulation was not successful.

Main effects & interaction effect

In order to test the hypotheses and provide evidence for the main effect, as well as for the interaction effect, to explore to what extent the effect of affirming the self on the

participants’ a) openness, and b) intention, and if this effect is moderated by the level of extraversion, a two two-way ANOVA’s were conducted.

To test H1, which states that individuals whose self was affirmed will have higher openness towards a persuasive message compared to individuals whose self was not affirmed, a two-way ANOVA was conducted. It contained the self-affirmation condition (vs. control condition), level of extraversion (high vs. low), and the interaction effect between the self-affirmation condition (vs. control condition) and level of extraversion (high vs. low) as independent variables on openness as dependent variable. The main effect of self-affirmation

on openness towards showed no significance for the health message F (1, 112) = .84, p = .361, η2 = .007), as well for the ad F (1, 106) = 2.84, p = .095, η2 = .026). Self-affirmed individuals (M = 5.36, SD = 1.09) were not more open towards the health message than not affirmed individuals (M = 5.55, SD = 1.12). Additionally, self-affirmed individuals (M = 3.54,

SD = 1.43) were not more open towards the ad than not affirmed individuals (M = 4.05, SD =

1.71). Levene’s test was not significant regarding both messages. These findings do no support hypotheses 1a, hence, H1a is rejected.

To test H2a, which states that the positive effect of self-affirmation on individuals’ openness towards a persuasive message is moderated by the level of extraversion, such that when the effect is self-affirmation is stronger for individuals low (vs. high) in extraversion, a two-way ANOVA was ran. The interaction effect between the affirmation (vs. no self-affirmation) condition and the level of extraversion (high vs. low) on openness, showed no significant difference regarding the health message F (1, 110) = 1.62, p = .21, η2 = .014), as well for the ad F (1, 104) = 1.17, p = .282, η2 = .011). Thus, the effect of self-affirmation was not moderated by level of extraversion, in which self-affirmed extraverts (M = 5.24, SD = 1.14) did not differ significantly on openness towards a health message from self-affirmed introverts (M = 5.48, SD = 1.04). Furthermore, the effect of self-affirmation was not

moderated by level extraversion on openness towards the ad, in which self-affirmed extraverts (M = 3.50, SD = 1.41) did not differ significantly from self-affirmed introverts (M = 3.58, SD = 1.47). Levene’s test was not significant regarding both messages. These findings do no support hypotheses 2a, hence, H2a is rejected.

To test H1b, which states that individuals whose self was affirmed will have higher intention to act in line with a persuasive message compared to individuals whose self was not affirmed, a two-way ANOVA was conducted with the self-affirmation condition (vs. control condition), level of extraversion (high vs. low), and the interaction effect between the

self-affirmation condition (vs. control condition) and level of Extraversion (high vs. low) as independent variables on intention. The main effect of self-affirmation on intention showed no significance regarding the health message F (1, 110) = 0.01, p = .91, η2 < 0.001), but did for the ad F (1, 104) = 4.19, p = .04, η2 = .039). In conclusion, self-affirmed people (M = 4.73, SD = 1.35) did not have higher intention regarding the health message than not affirmed people (M = 4.71, SD = 1.24). Additionally, self-affirmed individuals (M = 3.06, SD = 1.66) did not show significant less intention regarding the ad than not affirmed individuals (M = 3.81, SD = 1.92). Levene’s test was not significant regarding both messages. These findings do no support hypotheses 1b, hence, H1b is rejected.

To test H2b, which states that the positive effect of self-affirmation on individuals’ intention to act in line with a persuasive message is moderated by the level of extraversion, such that when the effect is self-affirmation is stronger for individuals low (vs. high) in extraversion, a two-way ANOVA was ran. The interaction effect between the self-affirmation (vs. no self-affirmation) condition and the level of Extraversion (high vs. low) on intention was not significant regarding the health message F (1, 110) = .29, p = .593, η2 = .003), as well as for the ad F (1, 104) = 1.66, p = .201, η2 = .016). Thus, the effect of self-affirmation was not moderated by level of extraversion, in which self-affirmed extraverts (M = 4.74, SD = 1.52) did not differ in intention regarding the health message compared to self-affirmed introverts (M = 4.72, SD = 1.19). Also, the effect of self-affirmation was not moderated by level extraversion on intention regarding the ad, in which self-affirmed extraverts (M = 2.98,

SD = 1.72) did not differ in intention compared to self-affirmed introverts (M = 3.15, SD =

1.63). Levene’s test was not significant regarding both messages. These findings do no support hypotheses 2b, hence, H2b is rejected.

Mediation effects

To test H3a, and H3b, which state that individuals’ openness towards a persuasive message has a positive relation on intention to act in line with a persuasive message, and this relation is further mediated by the use of resistance strategies, such that when the use of resistance strategies is high (vs. low) this effect gets weaker (vs. stronger), several mediation regression analyses using PROCESS were conducted. These analyses were checked with 5000 bootstrapping resamples to gather estimates of confidence intervals. In these analyses, openness towards a persuasive message was the independent variable, use of resistance strategies was the mediating factor and intention to perform the advocated behaviour was treated as the dependent variable.

The results indicate no significant mediation of contesting as a resistance strategy, neither on intention regarding the health message, (indirect = -.03, boot SE= .05, 95% BCI [-.17, .06]), nor on intention regarding the ad (indirect = .03, boot SE= .06, 95% BCI [-.07, .16]). Thus, there was no direct relation of contesting as a resistance strategy did on intention regarding the health message (b = .07, t(109) = .90, p = .38). Moreover, no direct relation was found of contesting as a resistance strategy on intention regarding the ad (b = .16, t(102) = 1.65, p = .10).

Furthermore, analyses indicated mediated relation of avoiding as a resistance strategy, neither on intention regarding the health message (indirect = .05, boot SE= .09, 95% BCI [-.11, .24]), nor on intention regarding the ad (indirect = -.04, boot SE= .06, 95% BCI [-.18, .06]). However, a negative direct relation was found between avoiding as a resistance strategy and intention regarding the health message (b = -.27, t(109) = -3.19, p = .002), next to the negative direct relation of avoidance as a resistance strategy on intention regarding the ad (b = -.17, t(102) = 2.04, p = .043). Nevertheless, this direct relation did not confirm a mediated relation of avoidance as a resistance strategy on intention regarding both messages.

Lastly, the analyses demonstrated no significant mediated relation of empowering as a resistance strategy, neither on the intention regarding the health message (indirect = -.01, boot SE= .05, 95% BCI [-.11, .10]), nor on intention regarding the ad (indirect = .04, boot SE= .06, 95% BCI [-.06, .18]). Subsequently, results showed that empowering as a resistance strategy did not have a direct relation with intention regarding the health message (b = -.13, t(109) = 1.87, p = .64), as well as that empowering as a resistance strategy did not have a direct relation with intention regarding the ad (b = .17, t(102) = 1.87, p = .064).

With regards to these results, hypothesis 3a and 3b are rejected. None of the proposed resistance strategies was found to have a mediating effect on the proposed relation between openness towards a persuasive message and intention to eat more fruit vegetables or the intention to click on the proposed advertisement.

Additional analyses

Self-esteem. Comparing the extravert condition to the introvert condition, inequal

distribution of variances on self-esteem were demonstrated, Levene’s F (1, 127) = 10.28, p = .011, η2 = .050). Correction was made for this inequality with the Welch test, in which a one-way ANOVA showed a significant difference between both groups F (1, 127) = 10.28, p = .009, η2 = .050), with a higher mean for the extravert condition (M = 5.64, SD = 1.02) compared to the introvert condition (M = 5.07, SD = 1.40) in self-esteem at the beginning of the experiment.

Resistance strategies. A paired-samples t-test was conducted to compare use of

resistance strategies when individuals face a health message and an ad. First, a significant difference in use of contesting as a resistance strategy between the health message (M = 3.18,

SD = 1.66) and the ad (M = 4.06, SD =1.49); t(106) = -4.58, p < 0.001 was indicated. Also, a

significant difference in use of avoiding as a resistance strategy between the health message (M = 2.98, SD = 1.56) and the ad (M = 4.33, SD =1.58); t(106) = -6.65, p < 0.001 was

reported. Last, a significant difference in use of empowerment as a resistance strategy

between the health message (M = 4.25, SD = 1.66) and the ad (M = 3.78, SD =1.46); t(106) = 2.54, p = 0.013 was found.

Discussion

The aim of this research was to examine if affirming the self has effects on openness towards persuasive messages together with greater intentions to act in line with the advocated behaviour depending on level of Extraversion. The hypothesize was that self-affirmation would induce more openness (H1a) and greater intentions (H1b). As well as, that the effect of self-affirmation was moderated by level of Extraversion, such that individuals with high levels of Extraversion would have less self-affirmation effects compared to individuals with low levels of Extraversion on openness (H2a) and intention (H2b). Lastly, it was hypothesized that individuals’ openness would have a positive effect on intention (H3a), and that this effect was mediated negatively by use of resistance strategies (H3b). In sum, self-affirmed

individuals were not more open, neither showed more intention. Also, the interaction effect of individuals’ level of Extraversion on self-affirmed individuals was not significant. Therefore, H1a, H1b, H2a, and H2b, are rejected. Also, individuals’ openness did not show to have a direct effect on individuals’ intention (H3a). Further this effect was not mediated by use of resistance strategies (H3b). Therefore, H3a and H3b are rejected.

Despite the used self-affirmation manipulation (Napper et al., 2009) to been proven to produce self-affirmation effects in prior research on health behaviours (Schüz et al., 2013; Scott et al., 2013), this was not confirmed in this study. A reason for not finding an effect of self-affirmation on individuals’ openness, or intention, could be that in previous research on alcohol consumption (Scott et al., 2013) and sun avoiding behaviour (Schüz et al., 2013), self-affirmation had only a positive effect on intentions to change their behaviour when

individuals were categorized as ‘high on risk’. Since in this study no such categorization was made this could indicate the alternative outcomes. Another plausible explanation why the

self-affirmation manipulation was not successful can be found in the difference in self-esteem between self-affirmed individuals (M = 5.56, SD = 1.07) and not affirmed individuals (M = 5.02, SD = 1.38) at the beginning of this study. Additionally, this potential cause of

differences in self-esteem could be caused by the higher level of self-esteem of extraverts (M = 5.64, SD = 1.02) than introverts (M = 5.07, SD = 1.40) when starting the experiment. This was not surprising, since Extraversion is strongly correlated with high self-esteem, which is also correlated with Openness (Robins, Tracy, & Trzesniewski, 2001). Starting the

experiment could also have induced feelings of excitement and novelty seeking under extraverts which can explain their higher level of self-esteem than introverts (Lee, Lee, & Hansen, 2017). Nevertheless, this difference in self-esteem does not explain why no moderating effect of people’s level of extraversion on openness and intention towards persuasive messages were found. Future research should determine if this finding is

generalizable. A possibility to achieve this is by examining the role of extraversion in closed experimental setting, in which on forehand would be determined people’s level of

extraversion and self-esteem. This can be considered as a limitation of this study, since in a review of McQueen & Klein (2006) it was confirmed most studies which prove effects of self-affirmation where conducted in lab experiment, measuring not only intention but also actual behaviour change. Another limitation of this study can be that the health promotion message retrieved from research of Epton and Harris (2008) was attempted to be replicated. This health message could have used different elements which influence people’s intention to eat more fruit and vegetables, but also a different self-affirmation manipulation could explain the why self-affirmation in that study was successful. Additionally, since was confirmed that depending on the persuasive message consumers apply different resistance strategies (Fransen et al., 2015b), future research should determine which strategies can be used directly in the field of health and advertising.

Conclusion

In conclusion, this research shows the challenge of establishing online experiments on self-affirmation which should induce effects on individuals openness and intention. Since people empower their own beliefs when facing persuasive health messages, next to

concerning a general advertisements due to deception, this can be confirmed as a limitation of affirmation as only effective in the domain of health behaviours. Even though, tested self-affirmation manipulations are developed (Napper et al., 2009), this research demonstrates that it is not applicable in every research under all circumstances, and openness towards a

persuasive message, and intention to act on in line with a persuasive message in general. To address further research, it should determine for which health and advertising behaviours sell-affirmation can be considered as resistance neutralizing strategy, and which campaigns, for example, do not threatens people’s self. As this would lead to self-affirmation having less effect. Furthermore, despite the differences which do exist regarding the personality trait Extraversion, future research should examine which factors determine extraverts and

introverts openness and intention when facing persuasive messages. This, so health campaigns and advertisements can be more effective when applying resistance neutralizing strategies as self-affirmation.

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Appendix A Base line measures scales

Self-esteem scale at the beginning of the experiment

Variable Items Min/Max score Source

Self-esteem How do you

currently feel about yourself? 1 = extremely negative 9 = extremely positive (Sherman et al., 2000)

General attitude towards advertisement (ATA) scale

Variable Items Min/Max score Source

General ATA 1. Overall, I consider advertising a good thing. 2. My general opinion about advertising is unfavourable. 3. Overall, I do like advertising. 1 = extremely negative 9 = extremely positive (Dianoux et al., 2014; Souiden et al., 2017)

Appendix B Dependent variables scales

Openness towards a persuasive message scale

Variable Items Min/Max score Source: changed

IV/DV accordingly Openness 1. To what extent are

you open towards the message?

2. To what extent do you feel resistant towards this ad?

1 = extremely negative 9 = extremely positive

(Jacks & O’brien, 2004)

Intention to act in line with the proposed health message scale

Variable Items Min/Max score Source:

Intention 1. To what extent do you intend to increase the amount of fruit and vegetables you eat in the next 7 days?

2. I intend to eat at least 2 portions of fruit and 250 grams of vegetables each day, in the next 7 days. 1 = definitely not intend to 9 = definitely intend to 1 = strongly disagree 9 = strongly agree

(Epton & Harris, 2008)

Intention to act in line with the proposed ad scale

Variable Items Min/Max score Source

Intention 1. To what extent would you intend to click on the ad? 2. What are the chances that you will click on this ad in the future? 1 = definitely not intend to 9 = definitely intend to 1 = extremely unlikely 9 = extremely likely (Gauzente, 2010)

Appendix C

Big Five level of extraversion scale

Variable Items Min/Max score Source

Extraversion Introversion 1. I see myself as someone who is outgoing, sociable. 2. I see myself as someone who is talkative. 3. I see myself as someone who has an assertive personality. 4. I see myself as someone who generates allot of enthusiasm. 5. I see myself as someone who is full of energy. 6. I see myself as someone who is reserved. 7. I see myself as someone who is sometimes shy, inhibited. 8. I see myself as someone who tends to be quiet.

1 = strongly disagree 9 = strongly agree

(Benet-Martinez & John, 1998)

Appendix D

Manipulation check self-esteem scale

Variable Items Min/Max score Source

Self-esteem 1. How do you currently feel about yourself? 2. I take a positive attitude toward myself. 3. I feel I am a person of worth. 4. I am able to do things as well as most other people. 5. On the whole, I am satisfied with myself.

1 = extremely negative 7 = extremely positive 1 = completely disagree 7 = completely agree (Sherman et al., 2000) (O’Malley & Bachman, 1983)

Manipulation check awareness self-affirmation

Variable Items Min/Max score Source

Awareness Did you know which purpose the

questionnaire about your personal values had during the experiment?

No/Yes (Sherman et al.,

2009)

Figure 1. Health promotion message

Figure 1. General advertisement

Online Qualtrics Experiment Dear participant,

First of all, I thank you for participating in this study. I would like to invite you to participate in a research study to be conducted under the auspices of the Graduate School of Communication, a part of the University of Amsterdam. The title of the study for which I am requesting your cooperation is ‘Personal values and preferences regarding different personalities'. In the online survey, a

questionnaire has to be filled in regarding your personal preferences. After this questionnaire, an ad and a health message will be shown in which you answer questions regarding these messages. To finish the experiment, eight questions regarding your personality will be asked. The study will take about 12 minutes and has to be finished in once. As this research is being carried out under the responsibility of the ASCoR, University of Amsterdam, we can guarantee that: 1) Your anonymity will be safeguarded, and that your personal information will not be passed on to third parties under any conditions, unless you first give your express permission for this. 2) You can refuse to participate in the research or cut short your participation without having to give a reason for doing so. You also have up to 24 hours after participating to withdraw your permission to allow your answers or data to be used in the research. 3) Participating in the research will not entail your being subjected to any appreciable risk or discomfort, the researchers will not deliberately mislead you, and you will not be exposed to any explicitly offensive material. 4) No later than five months after the conclusion of the research, we will be able to provide you with a research report that explains the general results of the research. For more information about the research and the invitation to participate, you are welcome to contact the project leader Ivar Schot at any time. Should you have any complaints or comments about the course of the research and the procedures it involves as a consequence of your participation in this research, you can contact the designated member of the Ethics Committee representing ASCoR, at the following address: ASCoR Secretariat, Ethics Committee, University of Amsterdam, Postbus 15793, 1001 NG Amsterdam; 020‐525 3680; ascor‐secr‐fmg@uva.nl. Any complaints or comments will be treated in the strictest confidence. We hope that we have provided you with sufficient information. We would like to take this opportunity to thank you in advance for your assistance with this research, which we greatly appreciate.

Kind regards, Ivar Schot

I hereby declare that I have been informed in a clear manner about the nature and method of the research, as described in the invitation for this study. I agree, fully and voluntarily, to participate in this research study. With this, I retain the right to withdraw my consent, without having to give a reason for doing so. I am aware that I may halt my participation in the experiment at any time. If my research results are used in scientific publications or are made public in another way, this will be done such a way that my anonymity is completely safeguarded. My personal data will not be passed on to third parties without my express permission. If I wish to receive more information about the research, either now or in future, I can contact Ivar Schot. Should I have any complaints about this research, I can contact the designated member of the Ethics Committee representing the ASCoR, at the following address: ASCoR secretariat, Ethics Committee, University of Amsterdam, Postbus 15793, 1001 NG Amsterdam; 020‐525 3680; ascor‐secr‐fmg@uva.nl. I understand the text presented above, and I agree to participate in the research study.

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What is your gender?

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What is your highest degree of education?

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In which country were you born?

▼ Afghanistan ... Zimbabwe

What is your age?

________________________________________________________________

Self-esteem at the beginning of the experiment.

The following question asks about your current state. Please answer the following question, choose the answer that most closely reflects you at this moment.

Extremely negative Moderately negative Slightly negative Neither positive nor negative Slightly positive Moderately positive Extremely positive How do you currently feel about yourself?

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General attitude towards advertisements.

The following questions ask about your general opinion towards advertisements. Please answer the following questions, choose the answer that most closely reflects you at the moment.

Strongly disagree Disagree Somewhat disagree Neither agree nor disagree Somewhat agree Agree Strongly agree Overall, I consider advertising as a good thing.

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