Reply to Mac Giolla and Ly (2019): On the reporting of Bayes factors in deception research

Bayes factors provide a continuous measure of evidence for one hypothesis (e.g., the null, H0) relative to another (e.g., the alternative, H1). Warmelink et al. (2019, Legal Criminol Psychol, 24, 258) reported Bayes factors alongside p‐values to draw inferences about whether the order of expected versus unexpected questions influenced the amount of details interviewees provided during an interview. Mac Giolla & Ly (2019) provided several recommendations to improve the reporting of Bayesian analyses and used Warmelink et al. (2019) as a concrete example. These included (I) not to over‐rely on cut‐offs when interpreting Bayes factors; (II) to rely less on Bayes factors, and switch to ‘nominal support’; and (III) to report the posterior distribution. This paper elaborates on their recommendations and provides two further suggestions for improvement. First, we recommend deception researchers report Robustness Regions to demonstrate the sensitivity of their conclusions to the model of H1 used. Second, we demonstrate a method that deception researchers can use to estimate, a priori, the sample size likely to be required to provide conclusive evidence.     

The Accuracy and Repeatability of Reconstructing Single Bullet Impacts Using the 2D Ellipse Method

When a bullet punctures a surface, it leaves behind a bullet impact, which can be analyzed in order to determine the origin and trajectory path from which a bullet was discharged using many different scientific methods to reconstruct a shooting scene. The purpose of the research was to test the accuracy and repeatability of reconstructing the impact angle of single bullet impacts using the ellipse method. The research was conducted by firing various calibers of ammunition into drywall panels positioned at varying angles of incidence from 88° until ricochet occurred. This was done in order to determine which caliber type and angle of incidence are most accurate and precise for reconstructing a shooting scene. The study examined four caliber types fired into drywall panels, with 5 repeated shots for each of the 11 angles of incidence (n = 220). Furthermore, 31 participants partook in the study to estimate a bullet impact angle of incidence utilizing the ellipse method. The results show that the best performance (accuracy and repeatability) is seen with the measurements of the 0.45 caliber ammunition. When angle of incidences is low (<64°), the performance (accuracy and repeatability) was seen to be better in all caliber ammunitions. Overall, the data provided for single bullet impacts deposited in drywall show that the ellipse method is useful in providing measurements for most crime scene reconstruction purposes and has also demonstrated that results vary depending on the type of ammunition, firearm, and angle of incidence being examined.     

Determining Line-Crossing Sequences Between Laser Printing and Writing Pen Using Coaxial Light

Determining the application sequence of hand-written pen ink and printer toner lines has attracted significant interest in questioned document examination. This study uses coaxial light to determine line-crossing sequences, with intersections observed under a VSC600 forensic document workstation and a Leica M205A Stereo-microscope. Results show that reflected light at intersections and color contrast between intersections and nonintersections was observed when a hand-written ink line passes over a toner line, while a toner line passing over a written line appeared dull, with no color contrast. The procedure was tested under a range of conditions, such as types of writing pens and laser printers, the writer, and writing pressure, with the latter playing an important role in the evaluation. To validate the results, a 90% detection rate and 98% accuracy rate were achieved from 50 samples of blind testing, which is more effective than optical microscopy.     

New Approaches to Age Estimation Using Palatal Suture Fusion

Palatal suture fusion has seen little testing and/or application due in part to an inadequately described relationship to formal age ranges. This study presents a modified scoring method that examines fusion on samples of modern documented adult males and compares two Bayesian approaches to age estimation. In the first analysis, American and Portuguese collections were used to derive univariate and multivariate transition analysis (TA) parameters, which combined with an informative prior, estimated age in a sample of modern Americans and Portuguese. For the second analysis, a Bayesian multiple linear regression (BMLR) used indicator statuses as the independent variables with age as the dependent variable. Highest posterior density regions (HPDRs) and highest posterior density intervals (HDI) were calculated for a holdout sample. Final age estimates for the methods were tested for accuracy using cumulative binomial tests at 75% and 90% coverages. The HPDRs from multivariate TA captured age better for younger individuals, but consistently underaged. The cumulative binomial tests on the BMLR results indicated the prediction intervals performed as expected, and we show they are narrower (more precise) and/or more accurate than the corresponding HPDR. The modified method presented here formally links palatal suture obliteration to age using two different approaches, one of which (BMLR) is new to the aging literature. The BMLR provided results free from bias and more reasonable age ranges while maintaining accuracy. We present a look-up table and a free, simple R file for users to download and run their own estimates with BMLR.     

Examination of Hacking and Blunt Force Skeletal Trauma

Hacking trauma is prevalent in forensic cases involving genocide and dismemberment, but research into the identification of this type of trauma is lacking. The present study examines characteristics of hacking and blunt force skeletal trauma in order to determine if there is a point at which blunt force trauma becomes distinguishable from hacking trauma. Ten implements with a range of blade angles (i.e., the striking surface of the implement) were used in conjunction with a controlled-force hacking device to impact 100 limb bones of white-tailed deer (Odocoileus virginianus). Observations of the trauma included the occurrence and degree of fragmentation, the entrance widths of the impacts, and composite scores of six hacking characteristics, especially the distinctive V-shaped kerf. ANOVA tests and regression analyses were used to assess the relationships between these characteristics and the blade angles. A significant relationship (p-value = 0.011) was found between the composite hacking scores and the blade angles, indicating that blunt force and hacking trauma can be distinguished. The entrance widths of the impacts exhibited a significant relationship with the blade angles (p-value = 0.037). There was also a significant relationship between the visibility of a V-shaped kerf in the bones (p-value = 0.003), with visibility decreasing around the 60° blade angle. These data should assist in establishing guidelines to differentiate hacking and blunt force skeletal trauma in cases where the implement is on a spectrum between sharp and blunt.     

A Qualitative Analysis of Vietnamese Adolescent Identity Exploration Within and Outside an Ethnic Enclave

Focusing on identity development explorations enables a greater understanding of contexts that affect immigrant adolescents. Utilizing thematic and grounded narrative analysis of 46 journal writings, during a one-month period, from first and second generation Vietnamese adolescents ranging in age from 15 to 18 (26 residents of a culturally and politically active ethnic enclave in Southern California; 20 adolescents living outside the enclave), this study establishes ways in which a focus on social context and exploration processes illuminates the complexity of immigrant adolescents’ identity formation. The two groups shared many similarities, including precipitants to exploration and steps undertaken to explore identity. However, two factors—social and cultural influences and emotional reactions—revealed interesting contrasts distinguishing enclave from non-enclave dwelling Vietnamese adolescents. Data also suggested that immigrant adolescents strive to integrate different domains of identity (ethnicity, gender, career) both with one another and with the historical, social, and cultural contexts they occupy.

Examining Temporal Associations Between School Connectedness and Early Adolescent Adjustment

This study examined (a) the associations between school connectedness and early adolescent adjustment problems over a 1 year period and (b) the equivalence of these associations across gender. Five hundred middle school students (53.4% female), initially in the 6th and 7th grades, participated in the two-wave study. Results from two-group cross-lagged panel analyses were consistent across boys’ and girls’ data. After controlling for baseline levels of adjustment problems, school connectedness predicted lower levels of early adolescent conduct problems 1 year later. Regarding the opposite direction of associations, and even after baseline levels of school connectedness were taken into account, conduct problems predicted lower levels of subsequent school connectedness. There were no cross-lagged associations between depressive symptoms and school connectedness, although elevated levels of baseline depressive symptoms predicted higher levels of subsequent conduct problems. Findings elaborate previous research by demonstrating that early adolescents actively shape the middle school environment.

《毒品识别与检验》实验教学体系创新性探索

目前公安教育普遍面临着实验教学体系薄弱的现状,在教学中为培养具有综合能力和创新能力的禁毒警察,改变现阶段禁毒民警业务知识薄弱的现状,我院禁毒学专业对“毒品识别与检验”实验教学体系进行改革,进行创新性教育的探索。