Modelling the spatial interactions between workplace and residential location

The use of Multinomial Logit (MNL) models specification for the simulation of residential location have been often criticised due to the Independence of Irrelevant Alternatives hypothesis (IIA) which does not allow for the existence of spatial correlation between residential zones. Moreover, it is not clear when and to what extent the influence of the workplace zone and accessibility to employment affect the residential location choices made by households; in other word, whether the residing choice is conditional to the workplace, or vice versa; or if such choices (residence and work place) are joint. In this paper, Nested Logit (NL) and Cross-Nested Logit models of residential location choice are specified and compared to MNL, to investigate the existence of spatial correlation between different locations. Furthermore, different assumptions are tested, considering the choice of residential zone and the joint choice of residential zone and work place zone. The models were estimated for the urban area of Santander (Spain). The results indicate that the inclusion in the model specification, of the spatial correlation between zones fit the data significantly better. Home-work journey times were a statistically significant factor in household location choice, whereas accessibility to employment had the correct sign but it was not statistically significant

Modelling transport and real-estate values interactions in urban systems

This article presents hedonic Multiple Linear Regression models (MLR), Spatial Auto-Regressive hedonic models (SAR), Spatial autoregressive hedonic in the Error term Models (SEM) and spatial Durbin hedonic Models (SDM) to estimate houses price variations in metropolitan areas as a result of changing environmental and accessibility conditions. The goodness of fit of the different models has been compared along with a series of hypotheses about the performance of the specifications considering spatial relationships between observations. The case study for such analysis was the urban area of Santander (Spain). It has been observed the models which considered spatial dependence between observations offered a greater degree of fit in a scenario showing strong spatial correlation in MLR residuals. The SEM model combined with a Queen-Contiguity matrix provided a good fit to the data and at the same time presented significant parameters with theoretically coherent signs. This model estimated increases of 1.8% for each additional transit line present in the areas of housing, as well as a reduction of 1.1% in their prices for each additional minute in travelling time to the Central Business District. Closeness to the train stations, however, implied reductions in house prices

Paying for parking : improving stated-preference surveys

This article describes an experiment which introduced random ranges into the variables used for the design of a stated preference survey and its effects on willingness to pay for parking. User behaviour at the time of parking was modelled to determine their willingness to pay in order to get to their final destination more quickly. Calculating willingness to pay is fundamental during the social and economic assessment of projects. It is important to correctly model how car parks and their users interact in order to get values which represent reality as closely as possible. Willingness to pay is calculated using a stated preference survey and by calibrating multinomial logit models, taking variable tastes into account. It is shown that a value with a low variability can be obtained for willingness to pay by correctly establishing the context of the choice and randomly changing the variables around an average value

The role of Doppler ultrasonography in vascular access surveillance—controversies continue

: Chronic hemodialysis therapy required regular entry into the patient's blood stream with adequate flow. The use of arteriovenous fistulas and grafts is linked with lower morbidity and mortality than the use of catheters. However, these types of accesses are frequently affected by stenoses, which decrease the flow and lead to both inadequate dialysis and access thrombosis. The idea of duplex Doppler ultrasound surveillance is based on the presumption that in-time diagnosis of an asymptomatic significant stenosis and its treatment prolongs access patency. Details of performed trials are conflicting, and current guidelines do not support ultrasound surveillance. This review article summarizes the trials performed and focuses on the reasons of conflicting results. We stress the need of precise standardized criteria of significant access stenosis and the weakness of the metaanalyses performed

Modelling gender perception of quality in interurban bus services

This paper models how women and men perceive the quality of interurban bus services and proposes a new methodology for detecting the highest priority service variables to act on. Service quality perception was modelled using both ordered logit and ordered probit models using data from revealed preference surveys. The methodology for detecting different priority levels uses the graphic representation of the relationships between influence in the model and average evaluation by users. The modification of certain variables increases the knowledge of how woman evaluate quality in bus services to help promote the use of interurban public transport. Statistical analysis of the data provides some conclusions such as: the proportion of users increases as age decreases for both men and women; and women seem to make shorter and more frequent trips than men. The best model for this data set was ordered logit. As expected, the most relevant variable is the relationship between quality and price. Other important variables are the condition of the bus and the frequency of service

La Salud Mental en los reconocimientos escolares.

El presente estudio analiza el abordaje de. los temas de salud mental en los denominados «reconocimientos escolares». Estos pueden ser considerados como unos instrumentos de marcado carácter preventivo (prevención secundaria) dentro de la sanidad escolar, parcela importante de la salud pública. Bajo este prisma, los límites de nuestro trabajo están en señalar la metodología para ese abordaje, así como analizar los resultados que con ella se obtienen

La Salud Mental en los reconocimientos escolares.

El presente estudio analiza el abordaje de. los temas de salud mental en los denominados «reconocimientos escolares». Estos pueden ser considerados como unos instrumentos de marcado carácter preventivo (prevención secundaria) dentro de la sanidad escolar, parcela importante de la salud pública. Bajo este prisma, los límites de nuestro trabajo están en señalar la metodología para ese abordaje, así como analizar los resultados que con ella se obtienen

La Salud Mental en los reconocimientos escolares.

El presente estudio analiza el abordaje de. los temas de salud mental en los denominados «reconocimientos escolares». Estos pueden ser considerados como unos instrumentos de marcado carácter preventivo (prevención secundaria) dentro de la sanidad escolar, parcela importante de la salud pública. Bajo este prisma, los límites de nuestro trabajo están en señalar la metodología para ese abordaje, así como analizar los resultados que con ella se obtienen

The role of Doppler ultrasonography in vascular access surveillance-controversies continue

Chronic hemodialysis therapy required regular entry into the patient's blood stream with adequate flow. The use of arteriovenous fistulas and grafts is linked with lower morbidity and mortality than the use of catheters. However, these types of accesses are frequently affected by stenoses, which decrease the flow and lead to both inadequate dialysis and access thrombosis. The idea of duplex Doppler ultrasound surveillance is based on the presumption that in-time diagnosis of an asymptomatic significant stenosis and its treatment prolongs access patency. Details of performed trials are conflicting, and current guidelines do not support ultrasound surveillance. This review article summarizes the trials performed and focuses on the reasons of conflicting results. We stress the need of precise standardized criteria of significant access stenosis and the weakness of the metaanalyses performed.Nephrolog