Modeling The Habitat Distribution Of Spiny Dogfish (Squalus Acanthias), By Sex, In Coastal Waters Of The Northeastern United States

A hierarchical Bayesian approach was used to model the spatiotemporal habitat distribution of spiny dogfish (Squalus acanthias) of both sexes (adults) caught during trawl surveys conducted by the Northeast Area Monitoring and Assessment Program in inshore coastal waters between New England and North Carolina during 2007-2013. The best model for predicting catch per unit of effort (CPUE) for this species includes the following relevant variables: bathymetry, sea surface temperature, salinity, chlorophyll- a (chl-a) concentration, season and time of survey, and a random spatial effect for both sexes. Predicted CPUE was related to depth for both sexes; females occurred in shallower waters than those in which males occurred. Also, more females than males were predicted to occur in warmer, less saline and more productive (higher chl-a concentration) waters. Seasonality and time of predicted CPUE indicated that the abundance of females was higher in inshore coastal waters in the spring and in the morning, and the abundance of males was greater in the afternoon and in the fall in the same area. Collectively, these results provide information that enhances our understanding of differences in habitat selection and spatiotemporal distribution of the 2 sexes of this species-information that can help to modify present management strategies for the U.S. Atlantic fishery

Heterogeneity in desired bus service quality from users' and potential users' perspective

Investigating on transit users' opinions represents a useful strategy to understand the level of quality of a service, and consequently pursuing the most convenient interventions for satisfying users and improving the service. On the other hand, an important issue for increasing the use of transit systems is linked to the necessity to attract new users, in addition to customize the current users. For this reason, it becomes fundamental to know also the perceptions of people who do not use transit systems with the aim to discover which are the reasons of their travel choices and particularly which are the most relevant transit service aspects for them. In this work, a Stated Preferences (SP) survey was conducted in order to investigate on both transit current and potential users' preferences. This kind of survey allows potential users opinions to be captured due to its peculiarity of the possibility to propose to interviewees hypothetical services and not only real services, which could not be judged by people who do not use the service. The collected data were adopted to calibrate discrete choice models such as Random Parameters mixed Logit models and Latent Class models. These models allow heterogeneity of users' opinions to be analysed. Calibrating this kind of models using data collected from both users and potential users permitted to capture the differences among users in their preferences about transit service quality, and the differences among potential users in their desired service quality. Model results showed some interesting findings concerning the differences of categories of users and potential users, and especially the diversity of preferences between people who know well the service and people who could become users even if they have not a real perception of it. We also calculated the Willingness-To-Pay (WTP), which allowed to discover that the WTP values obtained for the potential users are very much higher than the values obtained for the users. The proposed models can be also useful for the practitioners and transit operators to identify the best combination of the quality levels to assign to the various service aspects.This study has been possible thanks to the financing of the Spanish Ministry of Economy and Industry in the TRA2015-69903-R Project (co-funded with ERDF funds)

A Hierarchical Bayesian Modeling Approach for the Habitat Distribution of Smooth Dogfish by Sex and Season in Inshore Coastal Waters of the US Northwest Atlantic

The Smooth Dogfish Mustelus canis is an abundant, small coastal shark occurring along the U.S. Atlantic coast. Despite being targeted by a directed fishery and having recently undergone a stock assessment that found the population neither overfished nor experiencing overfishing, little is known about the spatial and temporal distribution of this species. Here, we used catch data from the spring and fall Northeast Area Monitoring and Assessment Program\u27s fishery-independent trawl surveys conducted between 2007 and 2016 and various environmental factors to perform hierarchical Bayesian modeling as a first attempt to spatially predict adult Smooth Dogfish CPUE in U.S. northwest Atlantic Ocean waters by sex and season. Relevant environmental variables differed between both sexes and seasons. Male and female CPUEs were similarly associated with lower salinity and shallower depth in the spring. During fall, male CPUE was associated with sea surface temperature and bottom rugosity, and female CPUE was associated with chlorophyll-a concentration, bottom rugosity, and year. Habitat modeling results predicted that areas of high male and female CPUEs would overlap during spring but strongly diverge during fall, when greater predicted CPUEs for males were distributed considerably farther north. These results suggest sexual segregation among Smooth Dogfish during fall, with the springtime overlap in distribution coinciding with the pupping and mating season in this population. This difference in distribution during fall may allow for a male-only directed fishery for Smooth Dogfish in the northern extent of the species\u27 range in waters near southern New England and Georges Bank

Passengers' Expectations on Airlines' Services: Design of a Stated Preference Survey and Preliminary Outcomes

ABSTRACT: As the competition between airlines grows, their customer-centered strategies are becoming increasingly popular. In this context, the marketing strategies are the result of investigations carried out directly on users, usually through the Customer Satisfaction Surveys. Investigating on airline passengers' preferences represents a useful action to pursue the most convenient strategy for increasing their satisfaction and improving the provided service. With this aim, we propose the design of a Stated Preference survey and the preliminary outcomes obtained from the analysis and modelling of the collected data. A deep study of the literature review drove us to consider the land services separately from the air ones. Even if the travel experience of an airline passenger starts at the airport, only the services provided by the airlines are the object of this study. The Stated Preference survey was designed with the aim to capture the passengers' desires on airlines' services by proposing hypothetical scenarios to them. The survey was addressed to the whole population of the University of Calabria (Italy). A sample of 1907 survey responses was obtained. For analyzing the collected data, discrete choice models have been calibrated to obtain the weights assigned by users to each service quality aspect included in the experiment

Multilingual Dependency Parsing and Domain Adaptation using DeSR

We describe our experiments using the DeSR parser in the multilingual and domain adaptation tracks of the CoNLL 2007 shared task. DeSR implements an incremental deterministic Shift/Reduce parsing algorithm, using specific rules to handle non-projective dependencies. For the multilingual track we adopted a second order averaged perceptron and performed feature selection to tune a feature model for each language. For the domain adaptation track we applied a tree revision ethod which learns how to correct the mistakes made by the base parser on the adaptation domain