Effectiveness of comparison overlays generated with DentalPrint software in bite mark analysis

Validation studies of the new DentalPrint software were carried out with experimental bite marks in pigskin. The bite marks were digitally photographed according to the ABFO guidelines for evidence collection. Dental casts used in the experiment were scanned in 3D and 2D, and comparison overlays were generated using DentalPrint and Adobe Photoshop software, respectively. Digitized photographs of the experimental bite marks and the biting edges obtained in the overlays were compared by two different examiners to analyze the impact of training and experience with the two methods. Receiver operating characteristic (ROC) analysis, sensitivity, specificity, and 95% confidence intervals for each cutoff point were calculated. The expert examiner using DentalPrint obtained the best results, with an area under the ROC curve of 0.76 (SE=0.057; CI at 95%=0.652-0.876). Fairly high specificity values were found for DentalPrint, and the best results were obtained for the cutoff value that discriminated between the examiner's response "biter" and the rest of the possible (specificity 97.9%, CI at 95%=93.2%-99.6%). Therefore, the results presented here indicate that DentalPrint is a useful, accurate tool for forensic purposes, although further research on the comparison process is needed to enhance the validity of bite mark analysis.     

Gone with the Storm: Rainfall Shocks and Household Wellbeing in Guatemala

This paper identifies the negative consequences of the strongest tropical storm ever to strike Guatemala on household welfare. Per capita consumption fell in urban areas, raising poverty substantially. Households cut back on food consumption and basic durables, and attempted to cope by increasing their adult and child labour supply. The mechanisms at play include the intensity of the shock, food prices and the timing of Agatha with respect to local harvest cycles. The results are robust to placebo treatments, migration and measurement error, and partly explain the increase in poverty in the country previously attributed solely to the collateral effects of the global financial crisis.     

Linguistic polarization and conflict in the Basque Country

This paper investigates the relationship between linguistic polarization and conflict in the Basque Country. During the 40 years of Franco??s dictatorship the use of the Basque language was banned. Therefore, there may be some linguistic roots underlying the conflict in the Basque Country. We show that at the municipality level, linguistic polarization reduces the level of conflict. This finding is robust to various ways of measuring linguistic and ideological polarization and the inclusion of other covariates. In addition, we find that a high level of the stock of human capital is beneficial for reducing conflict intensity.     

Age Estimation of Infants Through Metric Analysis of Developing Anterior Deciduous Teeth

This study provides regression equations for estimation of age of infants from the dimensions of their developing deciduous teeth. The sample comprises 97 individuals of known sex and age (62 boys, 35 girls), aged between 2 days and 1,081 days. The age‐estimation equations were obtained for the sexes combined, as well as for each sex separately, thus including “sex” as an independent variable. The values of the correlations and determination coefficients obtained for each regression equation indicate good fits for most of the equations obtained. The “sex” factor was statistically significant when included as an independent variable in seven of the regression equations. However, the “sex” factor provided an advantage for age estimation in only three of the equations, compared to those that did not include “sex” as a factor. These data suggest that the ages of infants can be accurately estimated from measurements of their developing deciduous teeth.     

Bayesian analysis of fingerprint, face and signature evidences with automatic biometric systems

The Bayesian approach provides a unified and logical framework for the analysis of evidence and to provide results in the form of likelihood ratios (LR) from the forensic laboratory to court. In this contribution we want to clarify how the biometric scientist or laboratory can adapt their conventional biometric systems or technologies to work according to this Bayesian approach. Forensic systems providing their results in the form of LR will be assessed through Tippett plots, which give a clear representation of the LR-based performance both for targets (the suspect is the author/source of the test pattern) and non-targets. However, the computation procedures of the LR values, especially with biometric evidences, are still an open issue. Reliable estimation techniques showing good generalization properties for the estimation of the between- and within-source variabilities of the test pattern are required, as variance restriction techniques in the within-source density estimation to stand for the variability of the source with the course of time. Fingerprint, face and on-line signature recognition systems will be adapted to work according to this Bayesian approach showing both the likelihood ratios range in each application and the adequacy of these biometric techniques to the daily forensic work.     

Losers' Second Chances and Control of the Party Machine: Aspirant Premiers in Regional Spain

In parliamentary democracies, controlling party machines has traditionally been a key asset for nascent political leaders, allowing them to continue in their position even after suffering a bad electoral start. Recent research suggests that in ‘old democracies’ this is no longer the case. Seeking to find whether this finding also applies to ‘young democracies’, the article analyses a dataset (built by the author) of candidates from the main national parties for the premiership of the Spanish Comunidades Autónomas, to ask whether being party chair increases the chances of ‘reselection’ after losing a first election. I conclude that in Spain, an example of a ‘young’ democracy, party machines still play a fundamental role at the start of politicians' leadership careers.