Talking up Social Capital : An Analysis of Social Voice

Social capital represents the potential networks open to an individual. But potential does not mean that it is exploited. Social voice is defined as the ability of an individual to make use of their social capital. We analyze a particular aspect of ‘social voice’, i.e. the ability to persuade others. Using a Bayesian framework we conclude that this should increase with education and the frequency with which the social network considers new ideas or issues. The impact of age is ambiguous. An individual’s knowledge should increase, but so too should the strength of prior beliefs within their social network. Empirical work based on Eurobarometer data confirms the importance of education and that social voice declines with age. It also finds evidence for a gender gap, which education only partially corrects, but marriage magnifies. Finally we confirm that social voice impacts on individual wellbeing.social capital; education marriage; gender

Interpersonal voice: Antecedents and consequences of speaking up within close relationships

This dissertation deals with people voicing concerns to a romantic partner in an attempt to change that romantic partner’s attitudes or behaviors either: a) to support the partner’s welfare (partner-benefiting voice) or b) to support the person’s own welfare (self-benefiting voice). Existing work on voice is reviewed and it is noted that the majority of prior research on voice has focused on how individual traits influence the use of voice and has ignored how the relational context between the parties might influence the use of voice. It is on this question that this dissertation focuses. Through three studies I assess how four relational factors: communal strength, commitment, perceived communal strength, and perceived commitment influence the exercise of self-and partner-benefiting voice. Additionally, in this dissertation, I also investigate the implications of expressing voice within close relationships, on relationship satisfaction. Whereas these studies yielded some evidence for a positive relationship between one’s retrospectively reported use of interpersonal voice and the four relational variables, daily diary reports of the use of interpersonal voice and actual behaviors indicative of interpersonal voice observed in the laboratory yielded evidence of the opposite relationship between the four relational variables and use of voice within close relationships. Furthermore, we found a negative relationship between one’s use of voice and one’s own relationship satisfaction. Through this work, I begin to address how relational context influences the use of voice and hope to ignite additional research into interpersonal voice in close relationships

Strength of forensic voice comparison evidence from the acoustics of filled pauses

This study investigates the evidential value of filled pauses (FPs, i.e. um, uh) as variables in forensic voice comparison. FPs for 60 young male speakers of standard southern British English were analysed. The following acoustic properties were analysed: midpoint frequencies of the first three formants in the vocalic portion; ‘dynamic’ characterisations of formant trajectories (i.e. quadratic polynomial equations fitted to nine measurement points over the entire vowel); vowel duration; and nasal duration for um. Likelihood ratio (LR) scores were computed using the Multivariate Kernel Density formula (MVKD; Aitken and Lucy, 2004) and converted to calibrated log10 LRs (LLRs) using logistic-regression (Brümmer et al., 2007). System validity was assessed using both equal error rate (EER) and the log LR cost function (Cllr; Brümmer and du Preez, 2006). The system with the best performance combines dynamic measurements of all three formants with vowel and nasal duration for um, achieving an EER of 4.08% and Cllr of 0.12. In terms of general patterns, um consistently outperformed uh. For um, the formant dynamic systems generated better validity than those based on midpoints, presumably reflecting the additional degree of formant movement in um caused by the transition from vowel to nasal. By contrast, midpoints outperformed dynamics for the more monophthongal uh. Further, the addition of duration (vowel or vowel and nasal) consistently improved system performance. The study supports the view that FPs have excellent potential as variables in forensic voice comparison cases

Strength of forensic voice comparison evidence from the acoustics of filled pauses

This study investigates the evidential value of filled pauses (FPs, i.e. um, uh) as variables in forensic voice comparison. FPs for 60 young male speakers of standard southern British English were analysed. The following acoustic properties were analysed: midpoint frequencies of the first three formants in the vocalic portion; ‘dynamic’ characterisations of formant trajectories (i.e. quadratic polynomial equations fitted to nine measurement points over the entire vowel); vowel duration; and nasal duration for um. Likelihood ratio (LR) scores were computed using the Multivariate Kernel Density formula (MVKD; Aitken and Lucy, 2004) and converted to calibrated log10 LRs (LLRs) using logistic-regression (Brümmer et al., 2007). System validity was assessed using both equal error rate (EER) and the log LR cost function (Cllr; Brümmer and du Preez, 2006). The system with the best performance combines dynamic measurements of all three formants with vowel and nasal duration for um, achieving an EER of 4.08% and Cllr of 0.12. In terms of general patterns, um consistently outperformed uh. For um, the formant dynamic systems generated better validity than those based on midpoints, presumably reflecting the additional degree of formant movement in um caused by the transition from vowel to nasal. By contrast, midpoints outperformed dynamics for the more monophthongal uh. Further, the addition of duration (vowel or vowel and nasal) consistently improved system performance. The study supports the view that FPs have excellent potential as variables in forensic voice comparison cases

Human roars communicate upper-body strength more effectively than do screams or aggressive and distressed speech

Despite widespread evidence that nonverbal components of human speech (e.g., voice pitch) communicate information about physical attributes of vocalizers and that listeners can judge traits such as strength and body size from speech, few studies have examined the communicative functions of human nonverbal vocalizations (such as roars, screams, grunts and laughs). Critically, no previous study has yet to examine the acoustic correlates of strength in nonverbal vocalisations, including roars, nor identified reliable vocal cues to strength in human speech. In addition to being less acoustically constrained than articulated speech, agonistic nonverbal vocalizations function primarily to express motivation and emotion, such as threat, and may therefore communicate strength and body size more effectively than speech. Here, we investigated acoustic cues to strength and size in roars compared to screams and speech sentences produced in both aggressive and distress contexts. Using playback experiments, we then tested whether listeners can reliably infer a vocalizer’s actual strength and height from roars, screams, and valenced speech equivalents, and which acoustic features predicted listeners’ judgments. While there were no consistent acoustic cues to strength in any vocal stimuli, listeners accurately judged inter-individual differences in strength, and did so most effectively from aggressive voice stimuli (roars and aggressive speech). In addition, listeners more accurately judged strength from roars than from aggressive speech. In contrast, listeners’ judgments of height were most accurate for speech stimuli. These results support the prediction that vocalizers maximize impressions of physical strength in aggressive compared to distress contexts, and that inter-individual variation in strength may only be honestly communicated in vocalizations that function to communicate threat, particularly roars. Thus, in continuity with nonhuman mammals, the acoustic structure of human aggressive roars may have been selected to communicate, and to some extent exaggerate, functional cues to physical formidability

Assessing the admissibility of a new generation of forensic voice comparison testimony

This article provides a primer on forensic voice comparison (aka forensic speaker recognition), a branch of forensic science in which the forensic practitioner analyzes a voice recording in order to provide an expert opinion that will help the trier-of-fact determine the identity of the speaker. The article begins with an explanation of ways in which human speech varies within and between speakers. It then discusses different technical approaches that forensic practitioners have used to compare voice recordings, and frameworks of reasoning that practitioners have used for evaluating the evidence and reporting its strength. It then discusses procedures for empirical validation of the performance of forensic voice comparison systems. It also discusses the potential influence of contextual bias and ways to reduce this. Building on this scientific foundation, the article then offers analysis, commentary, and recommendations on how courts evaluate the admissibility of forensic voice comparison testimony under the Daubert and Frye standards. It reviews past rulings such as U.S. v. Angleton, 269 F.Supp 2nd 892 (S.D. Tex. 2003) that found expert testimony based on the spectrographic approach inadmissible under Daubert. The article also offers a detailed analysis of the evidence presented in the recent Daubert hearing in U.S. v. Ahmed, et al. 2015 EDNY 12-CR-661, which included testimony based on the newer automatic approach. The scientific testimony proffered in Ahmed is used to illustrate the issues courts are likely to face when considering the admissibility of forensic voice comparison testimony in the future. The article concludes with a discussion of how proponents of forensic voice comparison testimony might meet a reasonably rigorous application of the Daubert standard and thereby ensure that such testimony is sufficiently trustworthy to be used in court

Variation in Glottalization at Prosodic Boundaries in Clear and Plain Lab Speech

Previous research on glottalization shows that this voice quality occurs more frequently at prosodic boundaries than in the middle of prosodic phrases. This study investigates ten speakers’ use of glottalization at prosodic boundaries in five passages read in both clear and plain lab speech. I analyzed each syllable in every passage for its voice quality (glottalized or modal) and for its prosodic boundary strength using the ToBI system. I found that glottalization is used regularly in phrase-final syllables, and that speakers use glottalization marginally more when preceded by a prosodic boundary than when phrase-medial. I found no evidence of a significant effect of speaking style on glottalization use.This work was partially supported by an Undergraduate Research Scholarship.This work was partially supported by the National Science Foundation (BCS-1056409).No embargoAcademic Major: AnthropologyAcademic Major: Linguistic

Avoiding overstating the strength of forensic evidence: Shrunk likelihood ratios/Bayes factors

When strength of forensic evidence is quantified using sample data and statistical models, a concern may be raised as to whether the output of a model overestimates the strength of evidence. This is particularly the case when the amount of sample data is small, and hence sampling variability is high. This concern is related to concern about precision. This paper describes, explores, and tests three procedures which shrink the value of the likelihood ratio or Bayes factor toward the neutral value of one. The procedures are: (1) a Bayesian procedure with uninformative priors, (2) use of empirical lower and upper bounds (ELUB), and (3) a novel form of regularized logistic regression. As a benchmark, they are compared with linear discriminant analysis, and in some instances with non-regularized logistic regression. The behaviours of the procedures are explored using Monte Carlo simulated data, and tested on real data from comparisons of voice recordings, face images, and glass fragments

Modeling the Decline in English Passivization

Evidence from the Hansard corpus shows that the passive voice in British English has declined in relative frequency over the last two centuries. We investigate which factors are predictive of whether transitive verb phrases are passivized. We show the increasing importance of the person-hierarchy effects observed by Bresnan et al. (2001), with increasing strength of the constraint against passivizing clauses with local agents, as well as the rising prevalence of such agents. Moreover, our ablation experiments on the Wall Street Journal and Hansard corpora provide support for the unmarked information structure of ‘given’ before ‘new’ noted by Halliday (1967)