How can the effects of the introduction of a new airline on a national airline network be measured? A time series approach for the Ryanair case in Spain

This paper quantifies the Ryanair Effect on the Spanish airline network. It proposes new methodology based on an advanced time series approach that allows both the direct and indirect effects of the incorporation of a new airline to be measured and that can be easily extrapolated to other airport systems. The findings show the mean indirect effect on other airlines, in absolute value, is 8.6 per cent of the total airport traffic, peaking at a maximum of almost 29 per cent. Also, surprisingly, there is found to be a negative indirect effect at only four of the ten airports analysed

Digital Filters for Maintenance Management

Faults in mechanisms must be detected quickly and reliably in order to avoid important losses. Detection systems should be developed to minimize maintenance costs and are generally based on consistent models, but as simple as possible. Also, the models for detecting faults must adapt to external and internal conditions to the mechanism. The present chapter deals with three particular maintenance algorithms for turnouts in railway infrastructure by means of discrete filters that comply with these general objectives. All of them have the virtue of being developed within a well-known and common framework, namely the State Space with the help of the Kalman Filter (KF) and/or complementary Fixed Interval Smoother (FIS) algorithms. The algorithms are tested on real applications and thorough results are shown

Measuring the LCC effect on charter airlines in the Spanish airport system

Using a robust transfer function model methodology, the present paper seeks to offer empirical evidence regarding the size and type of effects that low-cost carriers (LCCs) have had on traffic for charter carriers (CCs) in the Spanish airport system by geographic market. We show an unmistakable substitution relationship between CCs and LCCs in the latter’s typical niche markets, national and European flights, while there is no reaction from the CCs in the segment of international flights outside the EU. Furthermore, substitution effects are smaller between CCs and LCCs on the domestic level than effects between LCCs and network carriers (NCs) and slightly larger on the European level. Lastly, CC traffic’s different sensitivity to terrorist attacks, day of the week, air accidents and the economic crisis is also evident. CCs should therefore be considered an independent category that warrants individualized analyses

El impacto de las compañías de bajo coste en los aeropuertos andaluces

Dentro de las relaciones generales entre el aeropuerto y la economía urbana, destaca el análisis de la influencia que tienen los aeropuertos y el transporte aéreo sobre la industria turística. Concretamente, el aeropuerto más cercano a nuestras ciudades puede ser considerado como la puerta de entrada al turismo (Robertson, 1995), ya que las infraestructuras aeroportuarias y los servicios aeroportuarios son el primer y último lugar al que llegan/salen los turistas en sus vacaciones (Castillo-Manzano et al., 2010a). De esta forma, el aeropuerto le da al turista la primera impresión sobre la calidad de sus vacaciones, afectando a sus expectativas e intenciones para la decisión de compra del próximo destino. Sin embargo, la influencia entre el transporte aéreo y el turismo es bidireccional pues el turismo es, a su vez, un factor impulsor y en algunos casos un estimulador del cambio en el transporte aéreo, influenciando la demanda (Bieger & Wittmer, 2006)

The Speed Limits Debate: Is Effective A Temporary Change? The Case Of Spain.

Nowadays, speeding is one of the most relevant problems for traffic safety and most resistant to change in motorized countries. The key instruments in Speed Management Policy are speed limits. This road safety strategy is often established or changed, in order to save fuel during periods of rising prices. However, the relationship between speed limits and traffic accidents, is a topic widely discussed by researchers, and there seems to be some consensus about 'speed kills.' By applying advanced time series models of unobserved components, our study investigates the impact of a temporary reduction of maximum speed limits, implemented in Spain in 2011, in terms of fuel consumption and fatalities. Our analysis shows that this measure caused a positive effect, although with a limited statistical significance, on fuel consumption and a discrete reduction in road mortality. The costs associated with this temporary change seem to explain the discrepancies between these estimates and the forecasts that initially held the Spanish government

A unified approach for hierarchical time series forecasting

In this paper an approach for hierarchical time series forecasting based on State Space modelling is proposed. Previous developments provide solutions to the hierarchical forecasting problem by algebra manipulations based on forecasts produced by independent models for each time series involved in the hierarchy. The solutions produce optimal reconciled forecasts for each individual forecast horizon, but the link along time that is implied by the dynamics of the models is completely ignored. Therefore, the novel approach in this paper improves upon past research at least in two key points. Firstly, the algebra is already encoded in the State Space system and the Kalman Filter algorithm, giving an elegant and clean solution to the problem. Secondly, the State Space approach is optimal both across the hierarchy, as expected, but also along time, something missing in past developments. In addition, the present approach provides an unified treatment of top-down, bottom-up, middle-out and reconciled approaches reported in the literature; it generalizes the optimization of hierarchies by proposing combined hierarchies which integrate the previous categories at different segments of the hierarchy; and it allows for multiple hierarchies to be simultaneously adjusted. The approach is assessed by comparing its forecasting performance to the existing methods, through simulations and using real data of a Spanish grocery retailer

Automatic selection of Unobserved Components models for supply chain forecasting

For many companies, automatic forecasting has come to be an essential part of Business Analytics applications. The large amounts of data available, the short life-cycle of the analysis and the acceleration of business operations make traditional handmade data analysis unfeasible in such environments. In this paper, an Automatic Forecasting Support System comprising several methods and models is developed in a general State Space framework built in the so called SSpace toolbox written for Matlab. Some of the models included such as Exponential Smoothing and ARIMA are well-known, but we propose a new model family that has very rarely been used before in this context, namely Unobserved Components models. Additional novelties are that Unobserved Components models are used in an automatic identification environment and that their forecasting performance is compared with Exponential Smoothing and ARIMA models estimated with different software packages. The daily sold units dataset of a franchise chain in Spain spanning 166 products and 517 days of sales is used to assess empirically the new system. The system works well in practice and the proposed automatic Unobserved Components models compare very favorably with other methods and other well-known software packages in forecasting terms

An econometric analysis of the Spanish fresh fish market

This article seeks to analyse the factors that determine the dynamics of the balance between supply and demand in the Spanish fresh fish market. For this, the time-series of fresh fish landed in the 1973–2009 period is analysed through an estimation of the series of transfer function models. Among other things, the findings in the Spanish case show a complex relationship between the amount of fish landed and price; a clear substitution relationship between fresh fish and aquaculture; a negative impact of labour costs in a manual labour-intensive sector such as fishing, which in developed countries is being affected by an exodus of manpower to other sectors where there is less uncertainty surrounding labour conditions; the impact of Spain being barred from international fishing grounds a result of the delimitation of exclusive economic zones (EEZs); and the dwindling importance of fisheries traffic as a result of the port devolution process begun in Spain in the early 1990s. The non-significance of a priori key factors, such as the price of oil and Spain's entry into the EEC, can be explained by widespread energy subsidies and contradictions in the objectives of the Common Fisheries Policy, respectively

¿Puede el miedo a ir a la cárcel disminuir los accidentes de carretera?

El objetivo de esta ponencia es evaluar los efectos de la reforma del Código Penal español de diciembre de 2007 sobre el número de muertes en carreteras españolas y la posible duración de los mismos. La metodología empleada es un modelo multivariable de componentes no observables en una state space framework estimado por maximización del logaritmo de verosimilitud. En resumen, se han encontrado dos clases diferentes de efectos sobre los accidentes de carretera. Inicialmente, un mes antes de la aprobación de la reforma, se produce una reducción de un 28.4 por ciento sobre los muertos en carretera. Tras la aprobación de la ley y durante los 13 meses siguientes, se ha mantenido constante una reducción del 16 por ciento. En total con esta reforma se han reducido las muertes en carretera en unas 534 víctimas entre noviembre de 2007 y diciembre de 2008 y previsiblemente los efectos continuaron durante 2009

La gestión del agua y el uso de contadores individuales en el área metropolitana de Sevilla

Responsabilizar a los individuos de su propio consumo doméstico de agua es una de las medidas utilizadas para reducir la creciente demanda de este recurso y conseguir un consumo sostenible compatible con el objetivo de equidad. La utilización de contadores individuales, en lugar de colectivos, o la tarificación por habitante y no por vivienda son dos medidas encaminadas a conseguir dichos objetivos. En esta ponencia, se evalúan estas medidas aplicadas en el aérea metropolitana de Sevilla en las dos últimas décadas mediante un modelo de componentes no observable