Galit Nahari

Interacting personality traits? Smoking as a test case

We question whether it is profitable to look at smoking (both smoking status and the number of cigarettes smoked a day): (1) in terms of the personality traits of Extraversion, Neuroticism and Psychoticism; (2) in terms of their pairwise interactions; (3) with respect, rather, to impulsivity or sensation seeking; or (4) taking into consideration both these levels of analysis. Our sample comprised 121 smokers and 111 non‐smokers (mostly students). No interactions were predictive of smoking. Both Psychoticism and impulsivity were found to be central traits—thereby providing support for the notion that it is a better strategy to look at smoking in terms of both these levels of analysis. Copyright

Applying the Verifiability Approach to insurance claims settings:exploring the effect of the information protocol

Purpose Lie detection in insurance claim settings is difficult as liars can easily incorporate deceptive statements within descriptions of otherwise truthful events. We examined whether the Verifiability Approach (VA) could be used effectively in insurance settings. According to the VA, liars avoid disclosing details that they think can be easily checked, whereas truth tellers are forthcoming with verifiable details. Method The study experimentally manipulated notifying claimants about the interviewers intention to check their statements for verifiable details (the ‘Information Protocol’). It was hypothesized that such an instruction would (1) encourage truth tellers to provide more verifiable details than liars and to report identifiable witnesses who had witnessed the event within their statements, and (2) would enhance the diagnostic accuracy of the VA. Participants reported 40 genuine and 40 fabricated insurance claim statements, in which half the liars and truth tellers were notified about the interviewers intention to check their statements for verifiable details. Results Both hypotheses were supported. In terms of accuracy, notifying claimants about the interviewers intention to check their statements for verifiable details increased accuracy rates from around chance level to around 80%. Conclusion The VA, including the information protocol, can be used in insurance settings.

Are you as good as me at telling a story? Individual differences in interpersonal reality monitoring

We tested whether someones ability to tell a good story, in terms of the Reality Monitoring (RM) tool, affects the way s/he judges the stories told by others. Forty participants (undergraduate students) wrote down two statements – one about activities they did 30 minutes ago, and the other about a past event. Subsequently, they rated the quality of a target statement written by someone else. We found that the tendency to provide a not so detailed or a very detailed statement was stable across the two statements the participants wrote. Furthermore, this tendency affected how they judged the target statements: The richer a participants statements were compared to the target statement, the more critical the participant was in judging the target statement. These findings imply that RM is subject to biases which are related to individual differences. We discuss the implications of these findings for applying the RM lie detection tool in the field.

Systematic errors (biases) in applying verbal lie detection tools: richness in detail as a test case

The current paper describes potential systematic errors (or biases) that may appear while applying content-based lie detection tools, by focusing on richness in detail – a core indicator in verbal tools – as a test case. Two categories of biases are discussed: those related to the interviewees (i.e., interviewees with different characteristics differ in the number of details they provide when lying or telling the truth) and those related to the tool expert (i.e., tool experts with different characteristics differ in the way they perceive and interpret verbal cues). We suggested several ways to reduce the influence of these biases, and emphasized the need for future studies in this matter.

Can someone fabricate verifiable details when planning in advance? It all depends on the crime scenario

In the current study we examined the effect of having the opportunity to plan an alibi in advance on the suitability of the verifiability approach in two crime scenarios that differed in their opportunity to carry out innocent activities at the time of the crime. One hundred and two participants imagined being involved in stealing money either from a café at a time when it was open (allows innocent activities) or from a bank at a time when it was closed (does not allow innocent activities). We asked participants about their strategies and difficulties in preparing a verifiable alibi in advance, and to write down their prepared alibis. The participants in both groups found this task difficult and did not differ in the difficulties they experienced, however they differed in their strategies (plans to include true witnesses) and actual success in the task. Participants in the Café scenario provided 30% more verifiable details than the participants in the Bank scenario. Strategies and difficulties mentioned by the participants are presented in the paper, and the implications of the studys results on the application of the verifiability approach are discussed.

Insurance based lie detection: enhancing the verifiability approach with a model statement component

PURPOSE The Verifiability Approach (VA) is verbal lie detection tool that has shown promise when applied to insurance claims settings. This study examined the effectiveness of incorporating a Model Statement comprised of checkable information to the VA protocol for enhancing the verbal differences between liars and truth tellers. METHOD The study experimentally manipulated supplementing (or withholding) the VA with a Model Statement. It was hypothesised that such a manipulation would (i) encourage truth tellers to provide more verifiable details than liars and (ii) encourage liars to report more unverifiable details than truth tellers (compared to the no model statement control). As a result, it was hypothesized that (iii) the model statement would improve classificatory accuracy of the VA. Participants reported 40 genuine and 40 fabricated insurance claim statements, in which half the liars and truth tellers where provided with a model statement as part of the VA procedure, and half where provide no model statement. RESULTS All three hypotheses were supported. In terms of accuracy, the model statement increased classificatory rates by the VA considerably from 65.0% to 90.0%. CONCLUSION Providing interviewees with a model statement prime consisting of checkable detail appears to be a useful refinement to the VA procedure.

Elaborations on credibility judgments by professional lie detectors and laypersons: strategies of judgment and justification

Abstract Laypersons and professional lie detectors differ in biases of credibility judgment. The former are biased toward the truth, whereas the latter are biased toward lies. In an attempt to further understand these differences, the present study focused on the process of credibility judgment, rather than on its outcome. Forty-nine professionals (27 officers, 11 interrogators, 11 intelligence and secret services agents) and 40 laypersons (students) read an account of an event, and judged the credibility of the narrator; namely, the likelihood that he had actually experienced the event. Laypersons tended to believe the narrator more than professionals. The two groups also differed from each other in judgmental strategy (heuristic versus systematic) and justification (of either believing or disbelieving the narrator), and in the interpretation of the very same heuristics. Overall, the data showed that in credibility judgment laypersons and professionals process information differently: analyzing the very same statement, the former tended to consider it as true, whereas the latter tended to consider it as false. These data may partially account for the observed biases in credibility judgment of laypersons and professionals.

When the long road is the shortcut: a comparison between two coding methods for content-based lie-detection tools

ABSTRACT When using a content-based lie detection tool, a decision regarding veracity is made by evaluating the presence of specific content criteria within the interviewee’s account. This evaluation can be achieved either by counting the frequency of occurrence of the criteria (frequency counts; FC) or by using a scale to rate the intensity at which they appear in the entire text (scale rates; SR). In the current study, we compared these two coding methods with respect to their accuracy in determining veracity, and their intercoder and test–retest reliabilities. Fourteen coders coded the presence of perceptual and contextual details in true and false statements, each used the FC method for one set of 30 statements and the SR method for another set of 30 statements. One month later, eight of the coders recoded 28 statements. Results showed a significant advantage for the FC method over the SR method. While the coders perceived the SR method as less time-consuming than the FC method, accuracy level as well as intercoder and test–retest reliabilities were higher for the FC than for the SR method. These findings suggest that when using a content-based lie detection tool, FC coding should be preferred over SR coding.

The Applicability of the Verifiability Approach to the Real World

Abstract The real-world applicability of content-based tools for distinguishing lies from truths depends on several issues and challenges. For example, individual differences in language style or verbal ability make the decision on an individual case difficult, and interviewee acquaintance with a tool can hamper its effectiveness. The current chapter focuses on the verifiability approach (VA), a new content-based tool. The VA is centered on the knowledge that truth-tellers provide more verifiable details than liars. When liars try to make an impression of honesty by providing many details, they prefer to provide details that are difficult to verify over details that are easy to verify. Thus, the verifiability levels of interviewee accounts are used as indicators for veracity. The applicability of VA to the real world is discussed with respect to several factors, and compared to that of other verbal and nonverbal lie detection tools.

Using the verifiability of details as a test of deception: A conceptual framework for the automation of the verifiability approach

The Verifiability Approach (VA) is a promising new approach for deception detection. It extends existing verbal credibility assessment tools by asking interviewees to provide statements rich in verifiable detail. Details that i) have been experienced with an identifiable person, ii) have been witnessed by an identifiable person, or iii) have been recorded through technology, are labelled as verifiable. With only minimal modifications of information-gathering interviews this approach has yielded remarkable classification accuracies. Currently, the VA relies on extensive manual annotation by human coders. Aiming to extend the VA’s applicability, we present a work in progress on automated VA scoring. We provide a conceptual outline of two automation approaches: one being based on the Linguistic Inquiry and Word Count software and the other on rule-based shallow parsing and named entity recognition. Differences between both approaches and possible future steps for an automated VA are discussed.