Relative pleopod length as an indicator of size at sexual maturity in slipper (Scyllarides squammosus) and spiny Hawaiian (Panulirus marginatus) lobsters

Body size at gonadal maturity is described for females of the slipper lobster (Scyllarides squammosus) (Scyllaridae) and the endemic Hawaiian spiny lobster (Panulirus marginatus) (Palinuridae) based on microscopic examination of histological preparations of ovaries. These data are used to validate several morphological metrics (relative exopodite length, ovigerous condition) of functional sexual maturity. Relative exopodite length (“pleopod length”) produced consistent estimates of size at maturity when evaluated with a newly derived statistical application for estimating size at the morphometric maturation point (MMP) for the population, identified as the midpoint of a sigmoid function spanning the estimated boundaries of overlap between the largest immature and smallest adult animals. Estimates of the MMP were related to matched (same-year) characterizations of sexual maturity based on ovigerous condition — a more conventional measure of functional maturity previously used to characterize maturity for the two lobster species. Both measures of functional maturity were similar for the respective species and were within 5% and 2% of one another for slipper and spiny lobster, respectively. The precision observed for two shipboard collection series of pleopod-length data indicated that the method is reliable and not dependent on specialized expertise. Precision of maturity estimates for S. squammosus with the pleopod-length metric was similar to that for P. marginatus with any of the other measures (including conventional evidence of ovigerous condition) and greatly exceeded the precision of estimates for S. squammosus based on ovigerous condition alone. The two measures of functional maturity averaged within 8% of the estimated size at gonadal maturity for the respective species. Appendage-to-body size proportions, such as the pleopod length metric, hold great promise, particularly for species of slipper lobsters like S. squammosus for which there exist no other reliable conventional morphological measures of sexual maturity. Morphometric proportions also should be included among the factors evaluated when assessing size at sexual maturity in spiny lobster stocks; previously, these proportions have been obtained routinely only for brachyuran crabs within the Crustacea

Adversarial attacks on crowdsourcing quality control

Crowdsourcing is a popular methodology to collect manual labels at scale. Such labels are often used to train AI models and, thus, quality control is a key aspect in the process. One of the most popular quality assurance mechanisms in paid micro-task crowdsourcing is based on gold questions: the use of a small set of tasks of which the requester knows the correct answer and, thus, is able to directly assess crowd work quality. In this paper, we show that such mechanism is prone to an attack carried out by a group of colluding crowd workers that is easy to implement and deploy: the inherent size limit of the gold set can be exploited by building an inferential system to detect which parts of the job are more likely to be gold questions. The described attack is robust to various forms of randomisation and programmatic generation of gold questions. We present the architecture of the proposed system, composed of a browser plug-in and an external server used to share information, and briefly introduce its potential evolution to a decentralised implementation. We implement and experimentally validate the gold detection system, using real-world data from a popular crowdsourcing platform. Our experimental results show that crowd workers using the proposed system spend more time on signalled gold questions but do not neglect the others thus achieving an increased overall work quality. Finally, we discuss the economic and sociological implications of this kind of attack

All That Glitters is Gold -- An Attack Scheme on Gold Questions in Crowdsourcing

One of the most popular quality assurance mechanisms in paid micro-task crowdsourcing is based on gold questions: the use of a small set of tasks of which the requester knows the correct answer and, thus, is able to directly assess crowd work quality. In this paper, we show that such mechanism is prone to an attack carried out by a group of colluding crowd workers that is easy to implement and deploy: the inherent size limit of the gold set can be exploited by building an inferential system to detect which parts of the job are more likely to be gold questions. The described attack is robust to various forms of randomisation and programmatic generation of gold questions. We present the architecture of the proposed system, composed of a browser plug-in and an external server used to share information, and briefly introduce its potential evolution to a decentralised implementation. We implement and experimentally validate the gold detection system, using real-world data from a popular crowdsourcing platform. Finally, we discuss the economic and sociological implications of this kind of attack

Age and growth of swordfish (Xiphias gladius) caught by the Hawaii-based pelagic longline fishery

We verified the age and growth of swordfish (Xiphias gla-dius) by comparing ages determined from annuli in fin ray sections with daily growth increments in otoliths. Growth of swordfish of exploitable sizes is described on the basis of annuli present in cross sections of the second ray of the first anal fins of 1292 specimens (60−260 cm eye-to-fork length, EFL) caught in the region of the Hawaii-based pelagic longline fishery. The position of the initial fin ray annulus of swordfish was verified for the first time with the use of scanning electron micrographs of presumed daily growth increments present in the otoliths of juveniles. Fish growth through age 7 was validated by marginal increment analysis. Faster growth of females was confirmed, and the standard von Bertalanffy growth model was identified as the most parsimonious for describing growth in length for fish greater than 60 cm EFL. The observed growth of three fish, a year-old in size when first caught and then recaptured from 364 to1490 days later, is consistent with modeled growth for fish of this size range. Our novel approach to verifying age and growth should increase confidence in conducting an age-structured stock assessment for swordfish in the North Pacific Ocean

Les PME et l’accès aux marchés de capitaux en France : un état des lieux.

L’importance des «petites et moyennes valeurs» s’est renforcée de manière significative au cours du dernier cycle boursier. Des initiatives se poursuivent pour renforcer l’adaptation du cadre réglementaire à cette population très spécifique.PME, petites et moyennes valeurs, Eurolist, Alternext, Plan d’action des services financiers, AMF, introduction en bourse, liquidité, information financière.

A Novel Methodology for Manufacturing Firms Value Modeling and Mapping to Improve Operational Performance in the Industry 4.0 Era

Abstract In recent years there has been appreciable academic activity in manufacturing value creation resulting in that the ability to create value is based on the competence to make decisions and implement strategies; even though this evidence it is still difficult to understand where the company's weak points are located so value modeling approaching is arising. In this study Authors first report a qualitative review on value creation and modeling based on the identification, selection and analysis of about 100 papers, then specify the value concept within manufacturing companies. Within this context the Authors describe a novel methodology for manufacturing value modeling from strategic level down to operational improvements. The methodology and the related mapping and analysis tools have been co-developed with Siemens MES division within Industry 4.0 context. The Manufacturing Value Modeling Methodology (MVMM) is based on 5 steps: Value Map, Maturity Model, Gap and Process Analysis, Validation and Improvement Areas Definition. Through this methodological approach, a series of structured interviews allowing to construct the value map accordingly to the current company maturity model and the relationships between the strategic objectives and operational practices, capabilities, and methods. Combining the assessments interview with the Company' resources, infrastructure and IT structures, it is possible to establish a current level of the company. The mapping step is followed by a gap and process analysis, assessing most relevant areas for the creation of value aiming at constructing an interventions roadmap, setting out priorities and activities to be improved. The selection of the improvement areas defines process initiatives, KPIs and interventions to improve business alignment. To provide a practical view of the methodology a sample of the Value Modeler tool is presented and discussed

Consumer preferences for wild game cured meat label : do attitudes towards animal welfare matter?

Even though the European Union has imposed a mandatory labeling system for conventional meats, there is no mandatory labelling scheme for the so called \u201cminor meats\u201d- such as hunted wild game meat (HWGM). Thus, some European countries have implemented voluntary labelling programs certificating the origin of wild game meat. This study uses a discrete choice experiment to (1) assess consumer preferences for processed meat products (including wild game meat bearing a HWGM label), and (2) investigate whether consumers\u2019 attitudes towards animal welfare affects their food choice behavior for alternative meat products. Data was collected through an online survey conducted in Italy and consumer preferences for HWGM was estimated through a latent class logit model. Overall, results suggest that, even though HWGM label does not exist yet on the Italian market, it is appealing to Italian consumers and it will likely be accepted by the majority of them. However, consumers who are particularly concerned about animal welfare issues and animal rights showed the lowest level of the interest in the hunted game meat product and thus the presence of the HWGM label does not provide any benefit to them. Our findings have important implications for the development of successful marketing strategies and policy intervention in the HWGM sector at a national and European level

CrowdCO-OP : sharing risks and rewards in crowdsourcing

Paid micro-task crowdsourcing has gained in popularity partly due to the increasing need for large-scale manually labelled datasets which are often used to train and evaluate Artificial Intelligence systems. Modern paid crowdsourcing platforms use a piecework approach to rewards, meaning that workers are paid for each task they complete, given that their work quality is considered sufficient by the requester or the platform. Such an approach creates risks for workers; their work may be rejected without being rewarded, and they may be working on poorly rewarded tasks, in light of the disproportionate time required to complete them. As a result, recent research has shown that crowd workers may tend to choose specific, simple, and familiar tasks and avoid new requesters to manage these risks. In this paper, we propose a novel crowdsourcing reward mechanism that allows workers to share these risks and achieve a standardized hourly wage equal for all participating workers. Reward-focused workers can thereby take up challenging and complex HITs without bearing the financial risk of not being rewarded for completed work. We experimentally compare different crowd reward schemes and observe their impact on worker performance and satisfaction. Our results show that 1) workers clearly perceive the benefits of the proposed reward scheme, 2) work effectiveness and efficiency are not impacted as compared to those of the piecework scheme, and 3) the presence of slow workers is limited and does not disrupt the proposed cooperation-based approaches