Today's world is an interconnected global village. Communication and business transactions are increasingly conducted in non-native languages. Literature suggests that biases are present when communicating in non-native languages; that a truth bias is present in first language communication, and a lie bias in second language communication. Less than 10% of South Africa's population identifies with English, the lingua franca of the country, as a first language. Not much research in the presence of bias in second language communication has been published in the South African multi-lingual context. This study evaluated the presences of bias within deception frameworks such as the Truth Default State and the veracity effect. This study investigated whether deception detection can be improved by modifying the conditions under which statements are given by placing statement providers under cognitive load. The accuracy of veracity judgment language profiling software, LIWC2015, using published deception language profiles was compared against the results of the participating veracity judges. Results of the study were mixed. It was consistent with extant literature in a presence of a truth bias overall, but mixed in terms of a lie bias. The results supported the Truth Default Theory and veracity effect frameworks. LIWC2015 performed marginally better than human judges in evaluating veracity.

Nous sommes tous familiers avec les notions de tromperie et de détection du mensonge Nous admettons volontiers que mentir n’est pas un acte acceptable moralement. Le mensonge a toujours posé un problème moral. Par exemple, Aristote disait que « le mensonge est en soi méchant et coupable », Kant considérait la vérité comme un « devoir inconditionnel en toutes circonstances ». Machiavel a adopté une position différente en louant le mensonge au service de soi. Après avoir été un problème moral et juridique pendant des millénaires, la question du mensonge et de sa détection est devenue depuis une soixantaine d’années une question de recherche. Comment les gens réussissent-ils à tromper les autres ? Comment sont-ils susceptibles de croire les mensonges des autres ? Sont-ils capables de détecter lorsque quelqu’un leur ment ? Si oui, comment ? Pourquoi les gens sont-ils dupés ? Ces questions sont toujours d’actualité et cette thèse s’inscrit dans la continuité des recherches sur la détection du mensonge, dans le cadre de la détection sans instruments spécialisés.Les parutions scientifiques issues de la littérature sur la capacité humaine de détection du mensonge sont pessimistes et montrent que les individus font rarement mieux que le hasard. Si des explications ont été apportées, de nombreuses interrogations persistent encore, comme l’influence de certains aspects de la personnalité et de la cognition sur la capacité à détecter les mensonges. Nous avons ainsi mené plusieurs études expérimentales dans le but de répondre à certaines questions encore présentes. L’ensemble de nos résultats suggèrent que les traits de personnalité associés à une sensibilité aux émotions des autres nuisent à la bonne détection du mensonge. Nos résultats montrent, pour la première fois, que des fonctions cognitives, comme la reconnaissance de la prosodie, l’attention et la compréhension du discours sont impliquées dans la détection du mensonge. Enfin, ce travail de thèse a également examiné si des aspects de la personnalité et de la cognition influencent la capacité de détection de membres des forces de l’ordre. / We are all so familiar with the notions of deception and lie detection. We readily admit that lying is not morally acceptable. Lying has always been a moral problem. For example, Aristotle said that "falsehood is in itself mean and culpable" or Kant regarded the truth as "unconditional duty which holds in all circumstances.” Machiavelli has taken a different position by praising deceit in the service of self. After having been a moral and legal problem for millennia, the question of lies and their detection has become a question of research for about sixty years. How do people deceive others? How are people likely to believe the lies of others? Are they able to detect when someone is lying to them? And if yes, how? Why are people fooled? These questions are still relevant, and this thesis is part of the continuity of research on the detection of lies, in the context of detection without a specialized instrument.Scientific publications from the literature on the human capacity to detect lies are pessimistic and show that individuals rarely do better than chance. If explanations have been made, many questions still persist, such as the influence of certain aspects of personality and cognition on the ability to detect lies. We have conducted several experimental studies to answer some of the questions. All of our results suggest that personality traits associated with sensitivity to the emotions of others interfere with the capacity to detect lies. Our results show, for the first time, that cognitive functions, such as recognition of prosody, attentional processes and discourse comprehension, are involved in the detection of lies. Finally, this thesis also examined whether aspects of personality and cognition influence the detection ability of police officers (French Gendarmes).

The aim of this study was to investigate people’s ability to detect deception and if variables such as birth order, personality and suspiciousness affect this ability. The study was conducted at Växjö University with students as participants (n = 278). A film of two people arguing both for and against their own personal opinions was constructed and participants assessed credibility on a categorical scale (Honest/Dishonest). Neither birth order nor level of suspiciousness revealed significant differences as pertains to credibility attribution. In this study, personality traits showed small differences in that a low degree of Conscientiousness and possibly a high degree of Openness can predict lie bias (more correct classified lies). This study also showed that a truth and lie bias is predicted by positive respectively negative opinions. / Syftet med denna studie var att undersöka eventuella skillnader mellan människor och deras förmåga att upptäcka vilseledande information. Syskonplacering, personlighet och misstänksamhet ställdes mot deltagarnas trovärdighetsklassificeringar. Studien genomfördes på Växjö universitet och deltagarna bestod av studenter (n = 278). En film med två personer vilka argumenterade för och emot sina personliga åsikter konstruerades där deltagarna bedömde trovärdighet genom en kategorisk skala (Ärlig/Oärlig). Inga skillnader fanns mellan varken syskonplacering eller misstänksamhet och trovärdighetsbedömning. Personlighet gav små skillnader i trovärdighetsbedömning genom att låg grad av Conscientiousness och eventuellt hög grad av Openness predicerade lögnbias (fler korrekt klassificerade lögner) i denna studie. Studien visade även att sannings- och lögnbias prediceras av positiva respektive negativa åsikter i talarens påståenden.

<p>The aim of this study was to investigate people’s ability to detect deception and if variables such as birth order, personality and suspiciousness affect this ability. The study was conducted at Växjö University with students as participants (n = 278). A film of two people arguing both for and against their own personal opinions was constructed and participants assessed credibility on a categorical scale (Honest/Dishonest). Neither birth order nor level of suspiciousness revealed significant differences as pertains to credibility attribution. In this study, personality traits showed small differences in that a low degree of Conscientiousness and possibly a high degree of Openness can predict lie bias (more correct classified lies). This study also showed that a truth and lie bias is predicted by positive respectively negative opinions.</p> / <p>Syftet med denna studie var att undersöka eventuella skillnader mellan människor och deras förmåga att upptäcka vilseledande information. Syskonplacering, personlighet och misstänksamhet ställdes mot deltagarnas trovärdighetsklassificeringar. Studien genomfördes på Växjö universitet och deltagarna bestod av studenter (n = 278). En film med två personer vilka argumenterade för och emot sina personliga åsikter konstruerades där deltagarna bedömde trovärdighet genom en kategorisk skala (Ärlig/Oärlig). Inga skillnader fanns mellan varken syskonplacering eller misstänksamhet och trovärdighetsbedömning. Personlighet gav små skillnader i trovärdighetsbedömning genom att låg grad av Conscientiousness och eventuellt hög grad av Openness predicerade lögnbias (fler korrekt klassificerade lögner) i denna studie. Studien visade även att sannings- och lögnbias prediceras av positiva respektive negativa åsikter i talarens påståenden.</p>

Language is one of the main means of acquiring information about the world. An important debate in social psychology, linguistics and philosophy is how we come to believe information contained in statements we hear and read. Are we capable of assessing it and filtering it out, in case it is erroneous? Or do we rather tend to believe it? The experimental studies described in this thesis suggest that we strongly tend to believe statements we hear and read, even if we are aware of their falsity. Truth bias, as this tendency has been called, was detected both at the level of people’s memory and at the level of their judgments. Specifically, in a fake judicial context participants who read or listened to statements explicitly designated as true or false about a perpetrator tended to misremember false statements as true. Additionally, they were influenced by the false statements’ content in judgments they made about the perpetrators. Chapter 1 encompasses 5 Studies, all pointing to a strong truth bias, that, contrary to what is often assumed, may operate even in the absence of increased cognitive load (Studies 1–2). Studies 3–5 in Chapter 1 were methodologically-oriented, primarily aimed at testing the validity of the generalized truth bias established in Studies 1–2. Chapter 2 examines potential vigilance triggers that may reduce the truth bias. Manipulating the source of the false information (by informing participants that the speaker is either a defense attorney or prosecutor; Study 1), rendering participants accountable for their judgments (Study 2) or asking real judges to accomplish our experimental task (Study 3) did not reduce the truth bias. Nevertheless, offering participants financial incentives for providing an accurate judgment, eliminated both the memory-based and the judgment-based truth bias (Study 4). Based on the present experimental findings, I develop a model predicting that the truth bias is an intrinsic element of linguistic communication and hard to override. / Doctorat en Sciences psychologiques et de l'éducation / info:eu-repo/semantics/nonPublished

This study examined the ability of students to correctly discern between truthful and deceptive messages from a group of second language English speakers. Recent studies have found a ‘lie bias’ when making veracity judgments towards second language speakers. This lie bias may be problematic in a country such as South Africa where the majority of the population communicate, to a greater or lesser extent, in their second language. In this study participants (n=64) made classifications of 24 messages as either truthful or deceptive. The messages were created by second language English speakers who were asked to describe a truthful or deceptive event. The results revealed that there was a significant difference between the way that first and second language participants made their judgments. It is argued that this difference can be attributed to the notion that second language participants require more cognitive effort, than their first language counterparts, to understand and classify messages. / Psychology / M. A.(Psychology)