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We recorded the Eurasian Collared Dove (Streptopelia decaocto) and the African Collared Dove (Streptopelia roseogrisea) in the state of Guerrero. We recorded the former in five municipalities of the state, in areas with secondary and introduced vegetation. There the Eurasian Collared Dove has established, reproduced and increased its population. We recorded the African Collared Dove in captivity in the cities of Chilapa de Alvarez and Chilpancingo. The Eurasian Collared Dove exhibited a behavioural pattern of greater mobility and independence of human presence; in contrast, the African Collared Dove is a species that lives in close dependence on humans. We found that the Eurasian Collared Dove is spreading rapidly in Guerrero state, while the African Collared Dove is reproduced by people as an ornamental bird.

The benzylisoquinoline alkaloids of Annona muricata have been isolated, but their physiological or ecological role is unknown. The objective was to explore whether these secondary metabolites are involved in defense against phytopathogenic fungi. To do this, the alkaloidal response of 6-leaf seedlings of A. muricata was analyzed, previously inoculated with Colletotrichum gloeosporioides and Rhizopus stolonifer. Before and after inoculation, alkaloidal extracts of roots, stems, and leaves were obtained, and the antifungal activity was evaluated in vitro. The alkaloids anonaine, reticuline, nornuciferine, assimilobine, and coreximine were identified. C. gloeosporioides caused variable increases in the production of anonaine, reticuline and nornuciferine (10–1200%), while R. stolonifer only stimulated the increase of nornuciferin and anonaine (10%) in the stems and leaves. The alkaloidal extracts of inoculated seedlings increased the antifungal activity, both against the pathogen elicitor and against the second target pathogen. These findings suggest that the alkaloids participate in the antifungal defense mechanism.

This study was carried out in the Navachiste coastal lagoon, Mexico, surrounded by intensive agricultural and aquaculture activities that cause environmental pollution by the deposition of trace metal residues in the sediments of this coastal lagoon. The trace metals are bioaccumulated by benthic organisms such as the blue swimming warrior crab, Callinectes bellicosus, which inhabits this lagoon and is consumed by humans. Ninety-five C. bellicosus edible tissue samples were collected (April 2014–January 2015). The extraction procedure of the trace metals in edible tissue samples was carried out by acid digestion with nitric acid. Based on the Environmental Protection Agency (EPA) of the United States, two indices were used to measure health risk: the estimated daily intake (EDI) and the target hazard quotient (THQ). The hazard index (HI) was used to calculate the probability of adverse carcinogenic risk and the target hazard quotient per sample (MHI) to calculate the probability of developing a carcinogenic or non-carcinogenic risk. The analysis of variance (ANOVA) showed significant differences among trace metal concentrations (p < 0.01), but all trace metal concentrations in the edible tissues of C. bellicosus were higher than the maximum residual limits (MRLs). The highest EDI was for Zn, Fe, and Cu, showing that the consumption of these crabs might represent health risks. The THQ >1 was for Ni, Zn, Cd, and Cu, and the HI = 16 revealed the risk of C. bellicosus for high-level consumers. The MHI showed that 98% of samples presented a THQ >1, implying a high rate of bioaccumulation of trace metals by the crabs independent of the sampling site in the NAV. The presence of trace metals in the edible tissue of crabs reflects contamination by trace metals, and the indices results mean that the NAV lagoon is constantly polluted with trace metal residues by neighboring agriculture and aquaculture activities. These trace metal residues are being bioaccumulated in the edible tissues of C. bellicosus due to its feeding habits, resulting in a health risk if its consumption is high, including carcinogenic and non-carcinogenic risks.

The benzylisoquinoline alkaloids of

Introduction: Annona macroprophyllata Donn. Smith. (Annonaceae) (syn. Annona diversifolia Saff.) is a valued fruit tree species known as papausa. In Mexico and Central America, this fruit has become an important crop because of its tasty flavor and high pulp content. Its fruits are frequently damaged by the incidence of wasps of the genus Bephratelloides Girault (Hymenoptera: Eurytomidae), which develop inside the seeds. Objective: to report the interaction of Bephratelloides cubensis Ashmead during its life cycle in fruits of A. macroprophyllata. Methods: We periodically collected fruits in different states of growth recording a) oviposition, b) the moment of evident infection, c) the development of the wasps inside the seeds, and d) their emergence as adults. We also determined the proportion of damaged fruits and seeds. Results: The data indicate that wasps preferred to oviposit on fruits with a diameter of less than 8 cm, oviposition was more frequent between 11:00 am and 03:00 pm., and there was 26 % infestation of fruits, and 9 % of seeds. Conclusion: It is an obligatory interaction for the wasp, the highest proportion of attack on fruits was in the early stages of fruit development and control actions should focus on the protection of these early stages. Interacción de Bephratelloides cubensis (Hymenoptera: Eurytomidae) con frutos de Annona macroprophyllata en huertos de Chiapas, México. Introducción: Annona macroprophyllata Donn. Smith. (Annonaceae) es una especie de árbol frutal, conocida como papausa. En México y América Central, esta fruta se ha convertido en un cultivo importante y valorado debido a su delicioso sabor y la cremosa textura de su pulpa. Sus frutos son frecuentemente dañados por la incidencia de avispas del género Bephratelloides Girault (Hymenoptera: Eurytomidae), que se desarrollan dentro de las semillas. Objetivo: describir la interacción de Bephratelloides cubensis Ashmead durante su ciclo de vida en frutos de A. macroprophyllata. Método: Recolectamos frutos en diferentes estados de crecimiento registrando a) la ovoposición, b) el momento de la infección evidente, c) el desarrollo de las avispas dentro de las semillas, y d) su emergencia como adultos. También determinamos la proporción de frutas y semillas dañadas. Resultados: Los datos indican que las avispas preferían ovipositar en frutas con un diámetro de menos de 8 cm, la oviposición era más frecuente entre las 11:00 a.m. y las 3:00 p.m., y que había un 26 % de la infestación en las frutas y un 9 % en semillas. Conclusión: Es una interacción obligada para la avispa y la mayor proporción de ataque a los frutos fue en las etapas tempranas de desarrollo de frutos y las acciones de control se deberían enfocar a la protección de estas etapas.

Los registros nuevos de especies fortalecen el conocimiento de la biodiversidad y son la evidencia de que la comprensión de ésta es aún parcial, especialmente en áreas donde la diversidad es alta. Es importante seguir generando información que contribuya a robustecer la comprensión de la biota y los servicios que de ella derivan. En este estudio reportamos al charrán de Sandwich (Thalasseus sandvicensis) en dos localidades de la costa de Guerrero. Una localidad fue en Carrizal de Cinta Larga, municipio de Tecpan de Galeana, en febrero de 2010, diciembre de 2012, agosto y diciembre de 2013 y enero de 2015; y la otra en playa Casa de Piedra, municipio de Marquelia, en diciembre de 2011. La especie no está incluida en el listado avifaunístico de Guerrero. Nuestros registros confirman la presencia de la especie en la entidad.

En este artículo analizamos la imagen de nación que construye Vicente Huidobro a lo largo de la obra ensayística Balance Patriótico y que tiene como mayor característica la enfermedad. El imaginario creado por el autor fue escrito en el primer cuarto del siglo XX y se enmarca en una época de reevaluación de la imagen de nación. El ensayo deja en evidencia la existencia de un Chile dividido entre la luz del progreso y sus implicancias negativas. In this Article we analyzed the way Vicente Huidobro built the nation as a concept in his essay Balance Patriotico and its major characteristic, illness. The work built by the author was written in the first quarter of the 20th century and it is framed in a period of reevaluation of the way the nation was seen in those days. The essay shows that Chile was divided between the light of progress and its negatives implications.

Several species of Solanum produce secondary metabolites with antimicrobial activity. In the present study, the inhibitory activity of Solanum chrysotrichum, S. erianthum, S. torvum and S. rostratum against phytopathogenic Curvularia lunata was determined. Methanol extracts from roots, stems, leaves and fruits were evaluated by the method of mycelial inhibition on agar and the minimum inhibitory concentration (MIC) was determined on a liquid medium. To increase the antimicrobial activity, the combined activity of the most active extracts for each phytopathogen was also determined (a combination of intra and interspecies extracts). The results showed that 12 of the 16 methanolic extracts of Solanum species had antifungal effects against C. lunata. The extracts of S. rostratum and S. erianthum developed the highest activity (~80% inhibition and 28.4 MIC μg . ml–1), even, equal to or greater than, the reference fungicide. The mixture of the active extracts of S. chrysotrichum and S. torvum increased their activity. Various extracts affected the macro and microscopic morphology and most of them reduced the number of conidia of the fungus. This resulted in the capacity to control the vegetative growth and reproduction of C. lunata, the causal fungus of corn leaf spot disease.

espanolEl presente articulo tiene como proposito presentar la estimacion de la Huella Hidrica de la ciudad de Bogota generada en el ano 2014. La huella se define, de manera simplificada, como un indicador de consumo y contaminacion de agua dulce. Para ello fueron seleccionados cuatro sectores para evaluar el tipo de huella correspondiente en cada uno: sector domestico, industrial, agricola y residuos solidos. Se siguio la metodologia propuesta por Hoekstra et al. La huella hidrica total de los sectores evaluados se estimo en 9 489.58 millones de m3, donde el sector de mayor huella fue el agricola con 4 555.14 millones de m3, seguido por los sectores domestico, de residuos e industrial. Finalmente, es posible concluir la insostenibilidad de la huella hidrica y, por lo tanto, la vulnerabilidad de la ciudad frente a la disponibilidad del recurso. EnglishThis article presents the estimate of the Water Footprint of Bogota city generated in the year 2014. The water footprint is defined, in a simple way, as an indicator of consumption and pollution of freshwater. Four sectors were selected to evaluate the type of corresponding footprint in each: domestic, industrial, agricultural and solid waste. The methodology proposed by Hoekstra et al. was followed. The total water footprint of the evaluated sectors was estimated in 9 489.58 million m3, where the sector of higher footprint was the agricultural one, with 4 555.14 million m3, followed by the solid waste and industrial sectors. Finally, it can be concluded that the footprint is unsustainable and, therefore, the city is vulnerable considering the availability of the hydric resource.

El género Bursera es un componente característico de los bosques tropicales secos (BTS) de México y relevante para la conservación de estos hábitats, sin embargo, sus aspectos fenológicos son poco conocidos. Este estudio tuvo como objetivo caracterizar la fenología de Bursera simaruba Jacq. ex L y Bursera tomentosa (Jacq.) Triana & Planch y evaluar su relación con las variables ambientales. El seguimiento fenológico se realizó en una zona protegida del BTS de la región florística conocida como Depresión Central en Chiapas, México durante un ciclo anual (mayo 2017- abril 2018). Se seleccionaron 50 individuos adultos de cada especie y se registró la intensidad de sus fenofases reproductivas (botón floral, flor abierta, desarrollo de frutos y permanencia de frutos) y fenofases vegetativas (brote foliar, hojas maduras, senescencia) utilizando los métodos de Fournier. La estacionalidad y sincronía de cada fase se estimó mediante estadística circular calculando el vector medio (r) y la prueba Rayleigh (Z). Además, se categorizaron los tipos funcionales de su fenología vegetativa y reproductiva. Las etapas fenológicas en ambas especies fueron estacionales (r > 0.5), la floración y brote foliar sucedieron en un periodo breve mientras que el desarrollo vegetativo y las de producción de frutos fueron etapas más extendidas. Las fenofases reproductiva y vegetativa de Bursera simaruba y B. tomentosa son similares, las variables ambientales más correlacionadas (rs ≥ 0.6) a ellas fueron la temperatura y la humedad. El estudio de estas burseras permite conocer su dinámica en el BTS y con esto proponer planes de manejo de estas especies resiníferas.

In plants, the presence and distribution of specialized metabolites during the early stages of development are not documented enough, even though their biosynthesis is one of the most important strategies for survival. In this study, five alkaloids and four acetogenins were detected in Annona muricata L. during early development seedling, including three phases of root emergence and three of seedling formation. Hexane and alkaloid extracts were obtained from each organ, which were analyzed in a gas-mass chromatograph and in a high-performance liquid chromatograph coupled with a photodiode array UV detector (HPLC-DAD). This research shows the presence of the acetogenins cis-uvarimicin IV, mosinone, muricina B, and cis-annonacin-10-one, as well as of the alkaloids reticuline, coreximine, anonaine, asimilobine, and nornuciferine, both groups with a variable organ-specific distribution, related with the formation of organs and tissues.

Se registró la presencia de dos individuos de la tángara azul-gris (Thraupis episcopus) en un área urbana de la ciudad de Chilpancingo, estado de Guerrero. Estos registros son importantes porque aumenta en 250 km el límite suroeste conocido de distribución de la especie.

We present a microeconomic model for time use and consumption for workers with an improved treatment of the (technical) relations between goods and time. In addition to the traditional time and income constraints, an improved set of restrictions involving explicit relations between consumption of goods and time assigned to activities is included in two versions. In each version, a system of equations involving a subset of the consumer's decision variables is obtained, including (1) work time, (2) activities that are assigned more time than the minimum, and (3) goods that are consumed above the minimum. The system cannot be solved explicitly in the endogenous decision variables but is used to set a stochastic system for econometric estimation through maximum likelihood. The models are applied to analyze weekly time use and consumption data from Netherlands for year 2012. The results obtained by this new ``goods and time'' framework are compared with previous research in terms of the value of leisure and the value of work, showing substantial differences in the valuation of time.

Background. Phenological descriptions of plant species are used to understand cycles of foliation, flowering and fruiting. These studies provide useful means for understanding the relationships between plants and their environment. Question. What are the the foliar and reproductive strategies of four species of Annona living in the Deciduous Forest of Chiapas, Mexico? Species studied. Annona lutescens , A. macroprophyllata , A. reticulata and A. purpurea . Study sites. Three areas of deciduous forest were studied (16°31'36'' N, 92°58'25'' W, 16°28'82'' N, 92°57'48'' W, and 16°21'47'' N, 92°58'32'' W), located between the towns of Parral and Chiapa de Corzo, Chiapas, Mexico. Method. Stages of foliation, flowering, fruiting and senescence of 20 individuals per species were documented by written and photographic records during the course of a year. Variable time periods were adapted to the extended BBCH scale. The phenology was correlated with the stages of rain and drought by Spearman’s correlations Results. Phenological characteristics distinguish A. reticulata and A. lutescens as species with a reproductive strategy (flowering and fruiting) synchronized with the dry months, in contrast to A. purpurea and A. macroprophyllata , which show a reproductive strategy associated with the rainy season. The foliation of the four species is phenologically related to the rainy season. Conclusions. The species studied could be grouped according to their leaf pattern as brevideciduous or deciduous and according to their reproductive pattern as having long-term or short-term strategies.

The purpose of this research was to perform a preliminary inventory of the waste fat generated from beef cattle and fowl in Mexico that could be used for biodiesel production. Additionally, the CO2 emissions reduction that could be achieved by using the potential biodiesel to replace an energy-equivalent amount of fossil diesel was assessed. Based on national reports for the year 2014, it was estimated that the non-edible fat from beef cattle and fowl annually generated in Mexico is sufficient to produce 216.0 kt of biodiesel, which would furnish 8379 TJ. This amount is equivalent to 1.5% of the energy annually consumed in Mexico as fossil diesel for road transport. The potential 216.0 kt of animal fat-based biodiesel that can be produced annually could replace 198.3 kt of fossil diesel and thus allow a reduction in the WTW (well to wheels) emissions of 592.3 kt CO2, which represents 1.5% of the WTW CO2 emitted from the combustion of the fossil diesel used for road transportation in Mexico in the year 2014. © 2016 Society of Chemical Industry

The water quality of water bodies in Huasteca Potosina was assessed by the National Sanitation Foundation Water Quality Index (NFS WQI) depending on nine water quality parameters include physical, chemical, and biological properties. The water quality obtained at the sampling site 50-90 in the NSF-WQI range shows the medium quality. Results revealed that the Moctezuma River in Tanquian de Escobedo has low water quality with a score of 50, the Tancuilin and Axtla Rivers have good water quality, and the Moctezuma River (Tampamolón Corona), Amajac River, Valles River, Panuco River, Patitos Lagoon, Plan de Iguala Lagoon were all located in medium water quality. This indicates that the water quality of the Huasteca Potosina is irregular, due to the presence of contaminating agents coming from fertilizers, pesticides, domestic water, and residual water from the communities adjacent to the rivers and lagoons, causing an environmental impact to the aquatic ecosystems of the place. However, this research shows the importance of making use of the water quality index in this region, this to relate the environmental impacts responsible for the contamination of surface water and interpret the experimental data of this water quality monitoring to facilitate decision making and consider frequent monitoring of the quality of water bodies in the Huasteca Potosina.

Reporting and hypothetical biases are inherent to canonical methods of transportation data collection and had implied that analysis in this field has often neglected aspects that are strong behavioral drivers, such as uncertainty, physical effort or stress. Granular information on these aspects would allow measuring their valuation and/or addressing a pervasive source of endogeneity. Recent advances in miniaturization and data processing, as well as evidence that indicators from biosensors correlate with psychophysiological states and emotions, suggest that there is an opportunity to close this gap by collecting a new type of data from transportation users. This research works on leveraging this opportunity by putting forward, illustrating and testing a methodological framework to incorporate psychophysiological indicators gathered from biosensors into transportation choice behavioral modeling. The proposed framework adapts the integrated choice and latent variable approach by incorporating the psychophysiological responses as additional indicators of a latent psychophysiological state that covariates with utility. For the practical implementation of the proposed framework we also consider a specific form of aggregation of the indicators across time to avoid the curse of dimensionality arising from the unmanageably large number of folds for integration. The proposed framework is illustrated and validated using Monte Carlo simulations. Besides, a prototype field experiment was designed and performed to confirm the validity of three crucial components of the proposed framework: (i) the relation between transportation markers and emotions; (ii) the possibility of measuring those emotions through biosensors installed on travelers, (iii) and the validity of the proposed aggregation needed for practicality. In the experiment, a public transportation user travelled wearing a Printed Circuit Board that integrated tiny biosensors to capture electrodermal activity, heart rate variation, temperature and acceleration. Results provide positive evidence for the research questions, suggesting the convenience of developing larger data collection efforts in the future to take full advantage of the new framework.

Background and Aims: The phytochemistry study of Annonaceae has intensified in the last decades due to the discovery of secondary metabolites with antimicrobial activities. The inhibitory activities of extracts and compounds from these species for phytopathogens are less known. The antifungal activity of Sapranthus microcarpus was determined in vitro against six fungal pathogens of important crops. Methods: Hexane, methanol, and alkaloid extracts of the leaves and root and stem bark of S. microcarpus were evaluated to determine whether they could inhibit the mycelial growth of the phytopathogens. The combined activity of the most active extracts for each phytopathogen was also determined. The alkaloid liriodenine was isolated and identified as an antifungal principle. Key results: All extracts inhibited the growth of the six phytopathogens to some extent. The root bark alkaloid extract showed the highest activity. Fusarium oxysporum f. sp. lycopersici and Curvularia lunata were the most sensitive phytopathogens. Liriodenine was active against all the plant pathogens (minimum inhibitory concentrations of 125-500 nmol ml -1 ). Conclusions: Sapranthus microcarpus is a native natural resource with great phytochemical potential.

Annona purpurea grows in the areas of low elevation in deciduous forests of Mexico, those areas have marked rainy and dry seasons. This species produces more than 30 bioactive alkaloids that could have potential in the control of phytopathogens. This research provides data on the variation of the content and number of alkaloids during an annual cycle and the associated inhibitory potential of the compounds against three phytopathogenic fungi. For one year, alkaloidal extracts of stems and leaves were obtained every two months. The extract profiles were determined by gas chromatography with tandem mass spectrometry and their antifungal activity was examined in vitro. The alkaloids, annomontine and oxopurpureine, obtained from the roots and leaves, respectively, were also evaluated individually. The yields, profiles and activities of the extracts, as well as the abundance of annomontine and oxopurpureine in the extracts, were contrasted with the seasonality and phenological phases of the plant. The data indicate that the alkaloid content was higher at the height of the dry season. High yields also occurred during flowering. The strongest inhibitory effect was obtained from the root extracts during the last month of dry season. This finding seems to be explained by the higher chemodiversity of alkaloids in extracts from this season. Annomontine and oxopurpureine inhibited all three phytopathogens; however, they were not solely responsible for the activity of A. purpurea.

Many consumer choice situations are characterized by the simultaneous demand for multiple alternatives that are imperfect substitutes for one another, along with a continuous quantity dimension for each chosen alternative. To model such multiple discrete–continuous choices, most multiple discrete–continuous models in the literature use an additively-separable utility function, with the assumption that the marginal utility of one good is independent of the consumption of another good. In this paper, we develop model formulations for multiple discrete–continuous choices that accommodate rich substitution structures and complementarity effects in the consumption patterns, and demonstrate an application of the model to transportation-related expenditures using data drawn from the 2002 Consumer Expenditure (CEX) Survey.

We characterize heterogeneity in preferences and motivations regarding plug-in electric vehicles (PEVs)—including plug-in hybrids (PHEVs) and electric vehicles (EVs). Using survey data collected from 1754 new vehicle buying households in Canada in 2013, we segment respondents using two approaches that prove to be complementary. Preference-based segments were constructed using latent-class analysis of discrete choice experiment data. Potential PEV buyers were split into a “PEV-enthusiast” segment (8% of the sample) with extremely high valuation of PEVs and a broader “PHEV-oriented” segment (25%) that expressed moderately positive valuation of PHEVs. Preference-based segments also varied by respondents' valuation of specific attributes such as fuel savings. Our second approach constructed lifestyle-based segments using cluster analysis on a subset of potential early PEV buyers (33% of the total sample). The six lifestyle-based clusters varied in engagement in environment- and technology-oriented lifestyles, environmental concern and openness to change. Overall preferences were fairly similar across the clusters, though apparent motivations varied substantially by cluster as indicated by their differing engagement in lifestyles and environmental concern. Taken together, both approaches suggest that PHEVs are the most likely PEV to have broad market appeal and that car buyers have high degrees of heterogeneity in both preferences and motivations.

Elaboramos el listado avifaunístico de Ciudad Universitaria campus Sur de la Universidad Autónoma de Guerrero; un espacio urbano ubicado al sureste de la ciudad de Chilpancingo, Guerrero. Registramos 76 especies de aves pertenecientes a 53 géneros y 21 familias. Estacionalmente, 52 especies fueron residentes, 23 visitantes de invierno y una residente de verano. Icteridae, Tyrannidae, Parulidae y Cardinalidae fueron las familias con mayor proporción de especies. La riqueza de especies que registramos en este estudio es mayor a cualquier otra realizada en campus universitarios de México. Discutimos la importancia de llevar a cabo estudios avifaunísticos en áreas urbanas y suburbanas, y la relevancia de incluir áreas verdes en la planeación y diseño de los asentamientos humanos.

Registramos a la tángara azul gris (Thraupis episcopus) en la planicie costera del sureste del estado de Guerrero, México, en áreas urbanas con cobertura de árboles dispersos de especies nativas e introducidas. El área de distribución actual conocida para el taxón comprende tierras bajas del este de México, desde el centro-sur de Nuevo León hasta la península de Yucatán, incluido el este de Oaxaca y en la vertiente del Pacífico en la planicie costera de Chiapas. Sin embargo, no existen registros pre­vios publicados de la especie en Guerrero. Posiblemente T. episcopus es una especie que ha expandido su área de distribución en episodios de dispersión activa.

The Balsas’ province of southern Mexico has been defined as a natural unite based on its endemic taxa and environmental variables. It is recognized as a center of diversification, endemism and biogeographic transition. However, there are elements that allow us to distinguish 2 different biotic components within the province.We analyzed the distribution patterns of richness and beta diversity of birds, both total (migratory + resident) and resident. We used 2 coefficients of dissimilarity (1-Jclásicoy 1-Jmod.) to analyze beta diversity within the province. There are 3 areas with high species richness: 1) Northeastern; 2) Western and 3) in the center of the province of the Balsas. The beta diversity pattern suggests the existence of 2 components in the bird community that correspond to Eastern and Western sectors of the Balsas province. This is consistent with studies concerning the tendencies of the distribution of other taxa within the Balsas province. Therefore, we propose the division of the province into 2 faunal districts: Eastern and Western.

Summary In the current paper, we propose a new utility-consistent modeling framework to explicitly link a count data model with an event-type multinomial-choice model. The proposed framework uses a multinomial probit kernel for the event-type choice model and introduces unobserved heterogeneity in both the count and discrete-choice components. Additionally, this paper establishes important new results regarding the distribution of the maximum of multivariate normally distributed variables, which form the basis to embed the multinomial probit model within a joint modeling system for multivariate count data. The model is applied to analyzing out-of-home non-work episodes pursued by workers, using data from the National Household Travel Survey. Copyright © 2014 John Wiley & Sons, Ltd.

This paper develops a blueprint (complete with matrix notation) to apply Bhat’s (2011) Maximum Approximate Composite Marginal Likelihood (MACML) inference approach for the estimation of cross-sectional as well as panel multiple discrete–continuous probit (MDCP) models. A simulation exercise is undertaken to evaluate the ability of the proposed approach to recover parameters from a cross-sectional MDCP model. The results show that the MACML approach does very well in recovering parameters, as well as appears to accurately capture the curvature of the Hessian of the log-likelihood function. The paper also demonstrates the application of the proposed approach through a study of individuals’ recreational (i.e., long distance leisure) choice among alternative destination locations and the number of trips to each recreational destination location, using data drawn from the 2004 to 2005 Michigan statewide household travel survey.

Multiple-discrete continuous choice models formulated and applied in recent years consider a single linear resource constraint, which, when combined with consumer preferences, determines the optimal consumption point. However, in reality, consumers face multiple resource constraints such as those associated with time, money, and capacity. Ignoring such multiple constraints and instead using a single constraint can, and in general will, lead to poor data fit and inconsistent preference estimation, which can then have a serious negative downstream effect on forecasting and welfare/policy analysis. In this paper, we extend the multiple-discrete continuous extreme value (MDCEV) model to accommodate multiple constraints. The formulation uses a flexible and general utility function form, and is applicable to the case of complete demand systems as well as incomplete demand systems. The proposed MC-MDCEV model is applied to time-use decisions, where individuals are assumed to maximize their utility from time-use in one or more activities subject to monetary and time availability constraints. The sample for the empirical exercise is generated by combining time-use information from the 2008 American Time Use Survey and expenditure records from the 2008 US Consumer Expenditure Survey. The estimation results show that preferences can get severely mis-estimated, and the data fit can degrade substantially, when only a subset of active resource constraints is used.

Registramos el mielero pata roja (Cyanerpes cyaneus) en diversas localidades de la Sierra Madre del Sur. Esta especie figura en el inventario avifaunístico de Guerrero, pero se carecía de especímenes de estas poblaciones para colección científica y no se tenían registros para la región este de la Sierra Madre del Sur en el estado. Registramos individuos juveniles, adultos y un nido, lo que sugiere que son poblaciones reproductoras nativas. La ubicación geográfica de las localidades donde obtuvimos los registros para la especie permite inferir que ésta se distribuye en una franja altitudinal que se extiende de los 680 a los 1900 msnm, entre la Planicie Costera del Pacífico y la Sierra Madre del Sur. Esta área, con cobertura de selva mediana subcaducifolia y bosque mesófilo de montaña, constituye un corredor que ofrece condiciones adecuadas para la presencia de la especie.

This paper proposes a reformulation of count models as a special case of generalized ordered-response models in which a single latent continuous variable is partitioned into mutually exclusive intervals. Using this equivalent latent variable-based generalized ordered response framework for count data models, we are then able to gainfully and efficiently introduce temporal and spatial dependencies through the latent continuous variables. Our formulation also allows handling excess zeros in correlated count data, a phenomenon that is commonly found in practice. A composite marginal likelihood inference approach is used to estimate model parameters. The modeling framework is applied to predict crash frequency at urban intersections in Arlington, Texas. The sample is drawn from the Texas Department of Transportation (TxDOT) crash incident files between 2003 and 2009, resulting in 1190 intersection-year observations. The results reveal the presence of intersection-specific time-invariant unobserved components influencing crash propensity and a spatial lag structure to characterize spatial dependence. Roadway configuration, approach roadway functional types, traffic control type, total daily entering traffic volumes and the split of volumes between approaches are all important variables in determining crash frequency at intersections.